Maintenance Scheduling for Electrical Equipment

Facilities Instructions, Standards, and Techniques Volume 4-1B – Revised November 2005Maintenance Scheduling for Electrical Equipment U.S. Department of the Interior Bureau of Reclamation Denver, Colorado December 2005 REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY)T T T 2. REPORT TYPE T T 3. DATES COVERED (From - To)T 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER December 2005 4. TITLE AND SUBTITLE T Final FIST 4-1B, Maintenance Scheduling for Electrical Equipment 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 8. PERFORMING ORGANIZATION REPORT NUMBER Gary D. Osburn Bureau of Reclamation Hydroelectric Research and Technical Services Group Denver, Colorado 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Hydroelectric Research and Technical Services Group Bureau of Reclamation Denver Federal Center P.O. Box 25007 Denver, CO 80225-0007 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) FIST 4-1B 10. SPONSOR/MONITOR’S ACRONYM(S) Power Resources Office Office of Policy Bureau of Reclamation Mail Code D-5400 PO Box 25007 Denver CO 80225-0007 12. DISTRIBUTION / AVAILABILITY STATEMENT DIBR 11. SPONSOR/MONITOR’S REPORT NUMBER(S) Available from the National Technical Information Service, Operations Division, 5285 Port Royal Road, Springfield, Virginia 22161 13. SUPPLEMENTARY NOTES T 14. ABSTRACT This document establishes minimum recommended practices for maintenance of electrical equipment in Bureau of Reclamation hydroelectric power and large pumping plants. Included in this document are recommended maintenance activities, maintenance interval, and references. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON T Gary Osburn 19b. TELEPHONE NUMBER (include area code) a. REPORT b. ABSTRACT UL UL UL UL 63 303-445-2297 S Standard Form 298 (Rev. 8/98) P Prescribed by ANSI Std. 239-18 Facilities, Instructions, Standards, and Techniques Volume 4-1B Maintenance Scheduling for Electrical Equipment Hydroelectric Research and Technical Services Group U.S. Department of the Interior Bureau of Reclamation Denver, Colorado December 2005 Disclaimer This written material consists of general information for internal use only by Bureau of Reclamation operations and maintenance staff. Information contained in this document regarding commercial products or firms may not be used for advertising or promotional purposes and is not to be construed as an endorsement or deprecation of any product or firm by the Bureau of Reclamation. Standards. and Techniques Government Performance and Results Act generator step-up Hazardous Energy Control Program horsepower high-voltage direct current high potential tests Institute of Electrical and Electronics Engineers infrared job hazard analysis kilovolt kilovoltampere North American Electric Reliability Council National Electrical Safety Code National Fire Protection Association Office of Management and Budget operations and maintenance Occupational Safety and Health Administration Power Equipment Bulletin Power Operation and Maintenance preventive maintenance power system stabilizer reliability-centered maintenance Bureau of Reclamation Reclamation Safety and Health Standards Supervisory Control and Data Acquisition sweep frequency response analysis volts alternating current volts direct current Western Area Power Administration Western Electricity Coordinating Council working group crosslinked polyethylene iii .Acronyms and Abbreviations AC AEIC ANSI AVR BIL CBM CCVT CFR CIPP CO2 DC DGA EHV EPSS EPRI FIST GPRA GSU HECP hp HVDC Hipot IEEE™ IR JHA kV kVA NERC NESC NFPA OMB O&M OSHA PEB PO&M PM PSS RCM Reclamation RSHS SCADA SFRA Vac Vdc WAPA WECC WG XLPE alternating current Association of Edison Illuminating Companies American National Standards Institute automatic voltage regulator basic impulse insulation level condition-based maintenance Coupling capacitor/voltage transformers Code of Federal Regulations Critical Infrastructure Protection Plans carbon dioxide direct current dissolved gas analysis extra high voltage Emergency Power Standby Systems Electric Power Research Institute Facilities Instructions. . ....................................... 5........... Lead Acid (Gel Cel) Batteries ......5 Maintenance Schedule B Battery Chargers..............................................1 General.......................... Lead Acid Batteries ............................................. Arresters . 4............................3 Reliability Centered Maintenance ...............................1 Reclamation Standards ...... 2.................................. 1......................... Introduction ............2 Maintenance Schedule for Annunciators.......5 Job Plan Templates..............1 Maintenance.................................. Wet Cell................................................................................................. 2.................................................................................................................1.................................................................. 1........................4 Maintenance Schedules and Documentation.......................2 Preventive Maintenance ... 1........................2 Infrared Scanning .... 1............................................ 1........1 General.......................3........1 General.................1 General......... 1.....................1................................................... 1..........3 Maintenance Schedule B Valve Regulated....................2 Maintenance Schedule for Arresters......... Bushings.............................................................1 General................1............. 3................................. 5............... 1..................1 General...................... 1............... Annunciators...... 1..8 Limitations....3.....................................................................Table of Contents Page Revision Page ................................................................................ 4........................................ 1.........................................3............................ 1......2...1.......... 1.................3 Fault and Load Flow Studies/Equipment Ratings ....................2 Recommended Standards and References...................... 1................................................. 4................................................................ 4.... 1.. Batteries and Battery Chargers ........................................... 4.............. 4.............................................2............ 1............ ELECTRICAL EQUIPMENT MAINTENANCE SCHEDULES 2........................................................................5 Combination of Condition-Based and Preventive Maintenance ................................... 1..........................2 Maintenance Schedule for Bushings ...............................4 Maintenance Schedule B Vented Nickel Cadmium Batteries.............1......... 1................................................. 1............................. 5..............................9 Safety During Maintenance .......................................2 Standards and References................................................2 Maintenance Schedule B Flooded.........................................4 Condition-Based Maintenance .....................3 Maintenance and Test Procedures ................... v xi 1 1 1 1 2 3 3 4 4 5 5 5 6 7 7 8 8 8 9 9 10 10 10 11 11 11 11 11 12 13 14 14 14 14 15 ...........................6 Power O&M Forms ...................................................................... 3........ 1...7 Power O&M Reviews......................... 3................................... Contents (continued) Page 6. Buswork, Enclosures, and Insulators ................................................... 6.1 General............................................................................................ 6.2 Maintenance Schedule for Buswork and Enclosures 5-15 Kilovolts (kV) ..................................................................... 6.3 Maintenance Schedule for Buswork Insulators .............................. 7. Power Cables B Rated 5 kV and Above ................................................ 7.1 General............................................................................................ 7.2 Maintenance Schedule for Medium and High Voltage Cables Solid Dielectric and Oil-Filled........................... 8. Potheads and Stress Cones .................................................................... 8.1 General............................................................................................ 8.2 Maintenance Schedule for Potheads and Stress Cones .................. 9. Coupling Capacitors............................................................................... 9.1 General............................................................................................ 9.2 Maintenance Schedule for Coupling Capacitors ............................ 10. Circuit Breakers ..................................................................................... 10.1 General............................................................................................ 10.2 Molded Case Breaker Maintenance Schedule, Feeder and Critical Control and Protection Breakers .................................... 10.3 Low Voltage (600 V and Less [480 V]) Draw Out Air Breaker Maintenance Schedule ................................................... 10.4 Medium Voltage (601-15 kV Rated) Air and Air Blast Breaker Maintenance Schedule ................................................... 10.5 Medium Voltage (601-15,000 Vac) Vacuum Breaker Maintenance Schedule................................................................. 10.6 Medium and High Voltage SF6 Breaker Maintenance Schedule ...................................................................................... 10.7 High Voltage (Greater Than [>] 15,000 Vac) Oil Circuit Breaker Maintenance Schedule ....................................... 11. Communication Equipment .................................................................. 12. Control Circuits ...................................................................................... 12.1 General............................................................................................ 12.2 Maintenance Schedule for Control Circuits ................................... 13. CO2 Systems ............................................................................................ 13.1 General............................................................................................ 13.2 Maintenance Schedule for CO2 Systems ........................................ 15 15 15 15 16 16 16 16 16 17 17 17 17 17 17 18 19 19 20 21 22 23 23 23 23 24 24 24 vi Contents (continued) Page 14. Cranes, Hoists, and Elevators................................................................ 14.1 General............................................................................................ 14.2 Maintenance Schedule for Cranes, Hoists, and Elevators .............. 15. Electrical Drawings ................................................................................ 15.1 General............................................................................................ 15.2 Maintenance Schedule for Electrical Drawings ............................. 16. Emergency Lighting ............................................................................... 16.1 General............................................................................................ 16.2 Maintenance Schedule for Emergency Lighting ............................ 17. Engine Generators.................................................................................. 17.1 General............................................................................................ 17.2 Maintenance Schedule for Engine Generators ............................... 17.3 Maintenance.................................................................................... 18. Exciters and Voltage Regulators ........................................................... 18.1 General............................................................................................ 18.2 Maintenance Schedule for Exciters and Voltage Regulators ......... 19. Fire Detection, Fire Fighting Equipment, and Alarm Systems.......... 19.1 General............................................................................................ 19.2 Maintenance Schedule for Fire Detection, Fire Fighting Equipment, and Alarm Systems .................................................. 20. Fuses ........................................................................................................ 20.1 General............................................................................................ 20.2 Maintenance Schedule for Fuses .................................................... 21. Generators and Large Motors............................................................... 21.1 General............................................................................................ 21.2 References and Standards............................................................... 21.3 Maintenance Schedule for Generators and Large Motors .............. 22. Governors ................................................................................................ 22.1 General............................................................................................ 22.2 Maintenance Schedule for Governors ............................................ 23. Ground Connections .............................................................................. 23.1 General............................................................................................ 23.2 Maintenance Schedule for Ground Connections in Substations/Switchyards.............................................................. 25 25 25 25 25 25 26 26 26 26 26 27 27 28 28 28 29 29 29 29 29 30 30 30 30 31 32 32 33 33 33 33 vii Contents (continued) Page 24. Motors (< 500 hp) ................................................................................... 24.1 General............................................................................................ 24.2 Maintenance Schedule for Motors.................................................. 25. Personal Protective Equipment............................................................. 25.1 General............................................................................................ 25.2 Maintenance Schedule for Personal Protective Equipment Hot Line Tools............................................................................. 26. Relays and Protection Circuits.............................................................. 26.1 General............................................................................................ 26.2 Maintenance Schedule for Relays and Protection Circuits ............ 27. SCADA Systems...................................................................................... 27.1 General............................................................................................ 27.2 Maintenance Schedule for SCADA Systems ................................. 28. Security Systems ..................................................................................... 28.1 General............................................................................................ 29. Switches, Disconnect B Medium and High Voltage ............................. 29.1 General............................................................................................ 29.2 Maintenance Schedule for Disconnect Switches............................ 30. Transducers/Meters ............................................................................... 30.1 General............................................................................................ 30.2 Maintenance Schedule for Transducers.......................................... 30.3 Maintenance Schedule for Meters .................................................. 31. Transformers .......................................................................................... 31.1 General............................................................................................ 31.2 References and Standards............................................................... 31.3 Station/Distribution Transformers Under 500 kVA ....................... 31.3.1 General.............................................................................. 31.3.2 Maintenance Schedule for Station and Distribution Transformers.................................................................. 31.4 Instrument Transformers ................................................................ 31.4.1 General.............................................................................. 31.4.2 Maintenance Schedule for Instrument Transformers ....... 31.5 Dry-Type Power Transformers B 500 kVA and Larger ................. 31.5.1 General.............................................................................. 31.5.2 Maintenance Schedule for Dry-Type Power Transformers ...................................................... 33 33 34 34 34 34 35 35 37 38 38 38 38 38 39 39 39 39 39 40 40 40 40 40 41 41 41 41 41 42 42 42 42 viii Contents (continued) Page 31.6 Oil-Filled Power Transformers....................................................... 31.6.1 General.............................................................................. 31.6.2 Maintenance Schedule for Oil-Filled Power Transformers..................................................................... 32. Transformer Fire Suppression Systems ............................................... 32.1 General.............................................................................. 32.2 Maintenance Schedule for Transformer Fire Suppression Systems ........................................................ 33. Transmission Lines................................................................................. 33.1 General............................................................................................ 33.2 Maintenance Schedule for Transmission Lines.............................. 34. Blackstart Generators ............................................................................ 34.1 General............................................................................................ 34.2 Testing Schedule for Blackstart Generators ................................... 43 43 43 44 44 44 45 45 45 46 46 46 Appendices Page A Air and Oil Circuit Breaker Preventive Maintenance .............................. B Generator and Large Motor Preventive Maintenance .............................. C Disconnect Switch Preventive Maintenance ............................................ 47 55 59 ix . 6. Transformer Fire Suppression Systems NFPA 70B references to the 2002 Edition In Appendix A. Insulating Oil.1.5. Combination of Condition-Based and Time-Based Preventive Maintenance Section 1. and combined with Transducers Section 24. Potheads and Stresscones to Section 8 (to be with Cables) Section 9. Engine Generators (Emergency Standby Power Systems) and moved all subsequent section up one number. Section 17. Section 22. this is covered in sections on specific equipment Section 27. Added: Added Added: Moved: Added: Added: Moved: Deleted: Deleted: Added: Updated: Added Section 1. and changes are highlighted. Voltage Regulator Section 32. Operating Time xi .5. to Section 30. Job Plan Templates Section 1.Revisions Page November 2005 Summary of Major Revisions Note: Added sections are highlighted. Meters. Power O&M Forms Section 26. Coupling Capacitors and moved all subsequent sections up one number. . damaging seals.g.1 General This document is intended to establish standard practice as well as to give general advice and guidance in the maintenance of electrical equipment owned and operated by the Bureau of Reclamation. equipment and situations vary greatly. Maintenance recommendations are based on industry standards and experience in Reclamation facilities.usbr. 1990.. Industrial Press Inc. Power Equipment Bulletins are available only to Reclamation personnel and may be found on the intranet at http://intranet.1 It gives managers a level of assurance that equipment is being maintained. based on elapsed time. The goal is to achieve fewer. • • Preventive maintenance does have some drawbacks: • • • It is time consuming and resource intensive. run-time meter readings.” and maintenance costs in general. personal experience with the equipment. “reactive maintenance. planning. pg. etc.1. The intent of PM is to “prevent” maintenance problems or failures before they take place by following routine and comprehensive maintenance procedures.1.) in conjunction with these maintenance recommendations.gov/~hydrores/. It is easily understood and justified. and sound engineering and management judgment must be exercised when applying these recommendations. It can cause problems in equipment in addition to solving them (e.. shorter. making budgeting.. World Class Maintenance Management.1. and more predictable outages. 73. When properly practiced. or number of operations. and resource leveling possible. Terry Wireman. However. Other sources of information must be consulted (e.g. it generally prevents most major problems. unusual operating conditions. stripping threads). manufacturer’s recommendations. Specific technical details of maintenance are included in other documents which are referenced in this document. thus reducing forced outages. 1. 1. 7. It does not consider actual equipment condition when scheduling or performing the maintenance.2 Preventive Maintenance Preventive maintenance (PM) is the practice of maintaining equipment on a regular schedule.1 Introduction Maintenance 1. 1 . Some advantages of preventive maintenance are: • • It is predictable. pg. 2 .1. The maintenance recommendations in this document are based on a PM philosophy and should be considered as “baseline” practices to be used when managing a maintenance program. Industrial Press Inc.. efficient maintenance program. or CBM.2 This will reduce reactive (emergency and corrective) maintenance. the primary focus of the in-house maintenance staff should be scheduled maintenance. 1990. Scheduled maintenance should be the number one priority. effectively implemented. or a combination of these. maintenance managers may choose to apply a consciously chosen. This could result in important equipment not receiving needed maintenance. PM generally has proven to be reliable in the past and is still the core of most maintenance programs.Despite these drawbacks. and the pressure to “stay online” due to electric utility industry deregulation. which defeats the purpose of PM. care should be taken in applying PM recommendations. Whether utilizing a PM. RCM. Wholesale implementation of PM recommendations without considering equipment criticality or equipment condition may result in a workload that is too large to achieve. Scheduled maintenance should have a higher priority than special projects. May require additional monitoring of quantities like temperature and vibration to be effective. RCM seems very attractive in times of diminishing funding. Terry Wireman. May result in a “run-to-failure” or deferred maintenance philosophy for some equipment with its own PM. preventive maintenance has been the standard maintenance practice in Reclamation. Traditionally. 1. and properly documented reliability-centered maintenance (RCM) program or augment PM with conditionbased maintenance (CBM) practices. Some features of RCM are: • • Labor intensive and time consuming to set up initially. However.3 Reliability Centered Maintenance Reliability-centered maintenance programs are gaining in popularity and have been piloted in a few Reclamation power facilities with good results. To mitigate this problem. 32. 2 • World Class Maintenance Management. This may mean new monitoring equipment with its own PM or more human monitoring with multiple inspections. which may cause concern for some staff and managers. scarcity of skilled maintenance staff. RCM can eliminate some of the drawbacks of preventive maintenance and may result in a more streamlined. The goal of these programs is to provide the appropriate amount of maintenance at the right time to prevent forced outages while at the same time eliminating unnecessary maintenance. Implemented properly. For RCM to be a viable program at Reclamation facilities. and infrared scanning. etc. It requires knowledgeable and consistent analysis to be effective.• May require initial and later revisions to the maintenance schedule in a “trialand-error” fashion depending on the success of the initial maintenance schedule and equipment condition. it is nearly impossible to have an entirely conditionbased maintenance program. Monitoring. based on experience and monitoring. Testing on a periodic basis and/or when problems are suspected such as Doble testing. and properly documented RCM program. Some features of CBM include: • • • • Monitoring equipment parameters such as temperatures. Drawbacks to CBM include it being very difficult and expensive to monitor some quantities. maintenance schedules can be lengthened or perhaps shortened. and preventive maintenance schedules may provide the best information on when equipment should be maintained. vibrations. vibration testing. Because of these drawbacks. However. one can determine what maintenance was really necessary. using historical data. dissolved gas analysis. maintenance managers may choose to apply a consciously chosen. it must: • • • Be chosen as the local maintenance philosophy by management. and condition monitoring equipment and systems themselves require maintenance. In this manner. Be documented so that maintenance decisions are defensible.4 Condition-Based Maintenance This program relies on knowing the condition of individual pieces of equipment. Results in knowledgeable maintenance decisions which would reduce overall costs by focusing only on equipment that really needs attention. Careful monitoring of operator-gathered data. 1. Be implemented according to generally accepted RCM practices. 3 . Should result in a more manageable maintenance workload focused on the most important equipment. • RCM is not an excuse to move to a “breakdown maintenance” philosophy or to eliminate critical preventive maintenance in the name of reducing maintenance staff/funding.1. testing. to mitigate problems associated with a PM program. pressures. 1. effectively implemented.5 Combination of Condition-Based and Preventive Maintenance A combination of condition-based maintenance and preventive maintenance is perhaps the most practical approach.1. leakage current. By keeping accurate records of the “as found” condition of equipment when it is torn down for maintenance. 2 Recommended Standards and References Current editions of the following published standards and references should be maintained locally for use by electrical engineers. electrical supervisors. and Techniques (FIST) volumes that will be referenced in this volume. National Fire Protection Association (NFPA). telephone (303) 445-3655. also must be incorporated into a complete maintenance program. are based on power industry best practices. as defined in FIST volumes. 19 are included in FIST Volume 4-1A. For equipment not covered by other FIST volumes. To access Reclamation’s FIST volumes: • Printed FIST volumes: Regional and Area Offices – via Form DI-1 or 7-702 to D-7913. and other O&M personnel: • FIST Volume 1-1. All others contact National Technical Information Service.2. Recommended practices. including recommended intervals defined in FIST volumes. requirements defined in this document are the recommended practices. This FIST volume includes references to published standards produced by the Institute of Electrical and Electronics Engineers (IEEE™). 5285 Port Royal Road. electrical foremen. Virginia 22161. Power O&M. 19 . Instructions. in part.gov Select: Quicklist. 1.2 Standards and References 1. published standards. Reports & Data. and Reclamation’s experience maintaining equipment in hydroelectric powerplants. FIST Manuals.usbr. Hazardous Energy Control Program 4 .1 Reclamation Standards Electrical maintenance recommended practices for some equipment are contained in other Facilities.Maintenance Schedules and Records. Power Operation and Maintenance (O&M) Bulletin No. • • Intranet access to FIST volumes: http://intra. Variance from Reclamation electrical maintenance recommended practices. Denver Office via form MS-810 to D-7913.2. and other professional organizations. This FIST volume supersedes. Access to Internet FIST volumes: www. Operations Division.7).1. Other recommended maintenance practices are defined in Power Equipment Bulletins (PEB). Additional references to published standards may be found in other FIST volumes. Maintenance Scheduling for Mechanical Equipment. Springfield. as defined in instruction books. where they exist. Manufacturer’s maintenance requirements.gov Select: Programs & Activities. Mechanical maintenance portions of Power O&M Bulletin No. Power Program. Refer to the Power Review of O&M Directive and Standard and Guidebook for further information (see section 1.usbr. Standards. is acceptable provided that proper documentation exists to support the variance. functional tests. infrared scans. or a number of operations schedule.269 – Electric Power Generation.310-399 .available through IEEE/ANSI NFPA 70B – (2002 Edition) Recommended Practice for Electrical Equipment Maintenance NFPA 70E – Standard for Electrical Safety in the Work Place NFPA 101 . these are the activities scheduled on a time-based.National Electric Code (The handbook can be more useful than the code because of the included explanations and drawings. Transmission.) Electric Power Research Institute (EPRI) Electrical Power Reference Series. These activities are predictable and can be scheduled. Generally. and budgeted. cleaning. • • • • 1. published by McGraw Hill Westinghouse’s Transmission and Distribution Handbook and Westinghouse Applied Protective Relaying Handbook (These are out of print but may be available in personal libraries. staffed. and excitation system alignments. and Distribution American Electricians Handbook available through NFPA Industrial Power Systems Handbook by Beeman. governor. Some examples are visual inspections.3 Maintenance and Test Procedures 1. Maintenance Testing – Activities that involve the use of test equipment to assess condition in an offline state. measurement of operating quantities. oil tests.) NESC (National Electrical Safety Code) American National Standards Institute (ANSI) C2 and Handbook .• • • • • • • • • • Copies of all Electrical Maintenance and Safety FIST Volumes Copies of all Electrical Power Equipment Bulletins Manufacturers’ instruction/maintenance manuals for all equipment NFPA 70 . run-time-meter-based.3.Life Safety Code® Reclamation Safety and Health Standards Occupational Safety and Health Administration (OSHA) Code of Federal Regulations (CFR) 29 Part 1910.1 General Electrical maintenance activities fall into three general categories: • Routine Maintenance – Activities that are conducted while equipment and systems are in service. Volumes 1 through 13. lubrication.Electrical Safety Standards and CFR 29 Part 1910. These activities are predictable and can 5 • . 6 • . wedge tightness. turns ratio. infrared scanning is HIGHLY recommended as a regularly scheduled maintenance procedure. or number of operations basis but may be planned to coincide with scheduled equipment outages.3. 29. battery load tests.5.be scheduled. Since these activities are predictable. Each office must budget contingency funds for these events. It does not address followup work generated by routine maintenance or maintenance testing. AC Hipot tests. The IR camera operator must be trained to use the equipment and deal with complicating issues such as differing emissivities of surfaces and reflectivity. or higher. Effective infrared scanning and analysis require the following: • • The scanning equipment (IR camera and accessories) must be high quality and correctly maintained and calibrated. but this guide does not address these activities. meggering. infrared (IR) scanning is recommended as a regular maintenance procedure. core magnetization tests. partial discharge measurement. addresses standard tests for electrical equipment in Reclamation powerplants. This FIST volume addresses scheduling of maintenance activities in the first two categories. These activities are not predictable and cannot be scheduled because they are required after a forced outage. PEB No. meter. are recommended. 18-17. Several forced outages already have been avoided. It can be used not only for electrical equipment but also to detect mechanical and structural problems. Therefore. some offices consider them “routine maintenance” or “preventive maintenance. Infrared scanning and analysis have become an essential diagnostic tool throughout all industries and have been used in Reclamation to detect many serious conditions requiring immediate corrective action. or equipment failure/repair/replacement or when equipment deterioration is suspected. fires. and core ground tests. Also. 1. relay testing. alternating current (AC) high-potential (Hipot) tests. Infrared scanning is non-intrusive and is accomplished while equipment is in service. Some examples are Doble testing. Throughout this FIST volume. circuit breaker trip testing. Certified Level 1 Thermographer (e.” Some examples are Doble testing. The IR system operator must be able to analyze results using state-of-the-art software critical to successful interpretation of problems. pole drop tests. Electrical Testing Synopses.2 Infrared Scanning Annual infrared scans of electrical equipment are required by NFPA 70B. staffed. maintenance staff may be used for other activities such as improvements and construction. nor does it address diagnostic testing (with a few exceptions). Academy of IR Thermography) credentials.. high voltage direct current (HVDC) ramp tests.g. and budgeted. They may be scheduled on a time. • Diagnostic Testing – Activities that involve use of test equipment to assess condition of equipment after unusual events such as faults. HVDC ramp tests. 7). it is necessary to periodically conduct fault and load studies and to review equipment ratings for adequacy (continuous current. 1. Changes also occur as new equipment is added or upgraded inside the powerplant. current interrupting ratings. keeping track of equipment condition and maintenance— performed and planned—is critical.) and for coordination of protective relays. circuit breakers. and new construction.3. basic impulse insulation level [BIL]. These studies are typically performed by the Electrical Systems Group. momentary voltage. Underrated or misapplied electrical equipment can be hazardous to personnel. Call 303-445-2300 for more information. This is important for planning and conducting an ongoing maintenance program and provides documentation needed for the Power O&M Reviews (section 1. or reliability centered maintenance. 303-445-2850. This may mean that load ratings of various equipment and interrupting ratings of breakers and fuses are no longer adequate. Accurate drawings are very important to ongoing maintenance. 1. North American Electric Reliability Council (NERC) Planning Standards FAC-009-1 also requires periodic fault and load flow studies. Others may find it more cost effective to hire a contractor or use the resources in the Hydroelectric Research and Technical Services Group (D-8450). Recommendations can be converted into Job Plans or Work Orders in MAXIMO or another maintenance management system.• Experiences in the field have shown that technical knowledge of the equipment being scanned is highly desirable. testing. Requirements for reviewing equipment ratings are indicated where appropriate in the maintenance schedules in this volume. but they are essential during 7 . Maintenance recommendations contained in this volume should be used as the basis for establishing or refining a maintenance schedule.3 Fault and Load Flow Studies/Equipment Ratings Electrical power systems change as new generation and transmission lines are added or modified. and fuses to ensure safe and reliable operation. D-8440. Field offices with adequate resources may find it possible to achieve professional results by operating a local IR program. implementation of well-executed maintenance is possible. Once these job plans and work orders are established. accurate. The maintenance recordkeeping system must be kept current so that a complete maintenance history of each piece of equipment is available at all times. Regular maintenance and emergency maintenance must be well documented as should special work done during overhauls and replacement. Therefore. predictive. The availability of up-to-date drawings to management and maintenance staff is extremely important. to the integrity of the powerplant and power system. Whether performing preventive. momentary current. and current documentation is essential to an effective maintenance program.4 Maintenance Schedules and Documentation Complete. and to the equipment itself. etc. Each level of review is intended to assess compliance with accepted practices in operation. As stated in section 1.usbr. variance from these practices is acceptable provided that adequate justification is provided to reviewers.7 Power O&M Reviews Electrical maintenance is one area covered in the Power Review of O&M (PRO&M).gov/~hydrores/pomreview/. maintenance. PRO&M utilizes regularly scheduled Annual (self-assessment).6 Power O&M Forms Power O&M (PO&M) forms have been updated and placed on the intranet for facility use in documenting maintenance. 1. and in the references cited in this document.gov/forms/. Periodic (regionally conducted). Power Equipment Bulletins. accurate drawings are important to the continued safety of the staff working on the equipment. The electrical job plan templates include all PM activities prescribed in this volume and may be augmented to include manufacturer’s maintenance requirements and other sitespecific considerations.gov/~hydrores/pomreview/ and selecting “Job Plan Templates” from the menu on the left. select “Power O&M Forms” from the menu on the left or from the Reclamation forms Web site http://intra. These forms can be filled out online and printed or printed and completed by hand. Templates can be accessed on the Reclamation intranet at http://intra. The accepted practices for electrical equipment maintenance are defined in this and other FIST volumes.usbr. above. Word format files of the forms can be acquired from the Hydroelectric Research and Technical Services Group at 303-445-2300.1. Local development of complete job plans that match FIST volume requirements can be expedited by adopting these templates.usbr. In addition. and management. PO&M forms are available at http://intra. if modification for specific facility use is desired. and Comprehensive (Denver conducted) reviews. 1. 8 .5 Job Plan Templates Job plan templates have been created to assist in the development of site-specific MAXIMO Job Plans for electrical and mechanical PM.emergencies for troubleshooting.2. 1. 9 Safety During Maintenance Performing maintenance on electrical equipment can be hazardous. It should not be the sole source of information used in conducting maintenance activities. and Reclamation Safety and Health Standards (RSHS). Other references. All maintenance activity must be conducted in accordance with FIST Volume 1-1. A job hazard analysis (JHA) must be conducted as well.1. Hazardous Energy Control Program (HECP). 1. Visitors. contractors. 9 . and work experience are also necessary to fully understand and carry out the recommended maintenance.8 Limitations This FIST volume summarizes maintenance recommendations for electrical equipment and directs the reader to related references. training. and others working under clearances must be trained in HECP and must follow all JHA and clearance procedures. Electrical and mechanical energy can cause injury and death if not managed properly. 11. Annunciator operation is easily tested using the “Test” button provided on most annunciators and is considered an “operations” activity.1. Functional testing of annunciators also is recommended after a major outage or after modifications that affect wiring and cabling in the plant.6. Two aspects must be considered: (1) correct operation of the annunciator itself and (2) integrity of the alarm devices and interconnected wiring.4.1. Caution: Operating the alarm device may trigger unwanted control or protection actions as well as annunciation. However. 8. Functional testing is accomplished by (1) resetting the annunciator. this may be considered too extensive for time and resource limitations. where possible. it may be necessary to simulate contact operation with a “jumper” (or lifted lead) when device activation is not possible. In these cases.ELECTRICAL EQUIPMENT MAINTENANCE SCHEDULES 2. (2) closing (or opening) contacts at the alarm device.6. Verifying integrity of the alarm devices and interconnecting wiring requires a “functional test” of these circuits. 2. 3. It is recommended that the alarm device actually be triggered.9. 2.1 Annunciators General Annunciators provide essential plant condition status information to O&M personnel. for best assurance.3. Annex B. however. and (3) verifying that the correct annunciator window is activated. functional testing of those alarm points that indicate impending shutdown or failure that could be mitigated by operator action is still recommended.2 Maintenance Schedule for Annunciators Recommended Interval Each shift – staffed plants Each visit – unstaffed plants Annually Reference NFPA 70B.22 Reclamation Recommended Practice Maintenance or Test Operational test Functional test 10 . Annual functional testing of annunciators is recommended for best assurance of integrity. 21. Know what “should happen” by consulting up-to-date drawings before triggering alarms. 12 Manufacturer’s recommendation NFPA 70B.3. 3. online battery monitoring systems can greatly reduce maintenance required on battery systems and actually improve battery reliability and increase battery life. direct current [DC] insulation resistance.1 Batteries and Battery Chargers General Battery systems provide “last resort” power for performing communication. control.1 Annex I Table I. Computerized. power factor) Replace all silicon carbide arresters with metal oxide varistor type Infrared scan Reference NERC Planning Standard FAC-009-1 NFPA 70B. important to the health and readiness of battery systems. require regular maintenance as well. alarm. These arresters are static devices which require fairly infrequent maintenance. 20. 8. 4. Battery chargers.17 As soon as possible Annually 4.2. Most maintenance must take place while the associated circuit is de-energized. However.1 Manufacturer’s instruction manuals Doble Test Data Reference Book NFPA 70B.1 PEB No.2 Annex I Table I.9. Reclamation has had positive experience with these systems. 11 . Battery system maintenance should have highest priority. and they should be considered to supplement a maintenance program. 8. crucial visual inspections and infrared scans can take place while energized.2 Maintenance Schedule for Arresters Recommended Interval 5 years Quarterly to semiannually 3-6 years Ambient dependent 3-6 years Ambient dependent Maintenance or Test Review equipment rating Visual inspection with binoculars Clean insulator and check connections Doble test (power frequency dielectric loss.2.9. 3. and protective functions when other sources of power fail.1 Arresters General Lightning or surge arresters provide protection for important equipment from high-energy surges. all cells Monthly. 10 percent (%) of cells Annually. Table 1 Record on POM Form 133A FIST Volume 3-6. Lead Acid Batteries Recommended Interval Monthly Shift (charger meter) Monthly overall battery voltage with digital meter compare with charger meter Monthly. all cells Monthly (pilot cell) Quarterly (10% of all cells) Maintenance or Test Visual inspection Battery float voltage Reference FIST Volume 3-6. pilot cells Quarterly. Table 1 Record on POM Form 133A FIST Volume 3-6. Table 1 Record on POM Form 133A FIST Volume 3-6. annually if capacity less than 90% Monthly. pilot cells with digital meter Quarterly. all connections Capacity testing 5 years.4. Wet Cell.17 Specific gravity Temperature Connection resistance Annually. Table 1 FIST Volume 3-6.2 Maintenance Schedule – Flooded. test all wash devices and inspect all safety equipment Annually Safety equipment inspection Infrared scan cells and connections Battery monitoring system According to manufacturer’s recommendations Manufacturer’s instruction manual 12 . Table 1 Record on POM Form 134A FIST Volume 3-6 IEEE 450-1995 FIST Volume 3-6 IEEE 450-1995 NFPA 70B 20. Table 1 Record on POM Form 133A Cell float voltage FIST Volume 3-6. Table 3 IEEE 1188-1996 Connection resistance Internal resistance Capacity testing Annually and semi-annually If capacity test less than 90% Monthly. Table 3 FIST Volume 3-6. Table 3 Record on POM Form 133B Cell float voltage Temperature FIST Volume 3-6. all cells with infrared camera Quarterly (25%) Annually (100%) Quarterly FIST Volume 3-6. Table 3 Record on POM Form 133B FIST Volume 3-6. Table 3 Shift (charger meter) Monthly compare digital voltmeter with charger meter Monthly pilot cells. test all wash devices and inspect all safety equipment Annually Safety equipment inspection FIST Volume 3-6. Table 3 IEEE 1188-1996 Infrared scan cells and connections Battery monitoring system NFPA 70B 20.17 According to manufacturer’s recommendations Manufacturer’s instruction manual 13 . Semi-annually.4. Table 3 Record on POM Form 134B FIST Volume 3-6. Table 3 Record on POM Form 134B FIST Volume 3-6. check all individual cells with digital voltmeter Quarterly.3 Maintenance Schedule – Valve Regulated. Lead Acid (Gel Cel) Batteries Recommended Interval Monthly Maintenance or Test Visual inspection Battery float voltage Reference FIST Volume 3-6. 1 Bushings General Bushings are critical components of medium and high voltage circuit breakers and transformers. charger meter. check each cell with digital voltmeter Quarterly (pilot cell) Annually. or at least during an outage on that equipment.4 Maintenance Schedule – Vented Nickel Cadmium Batteries Recommended Interval Monthly. Table 4 Monthly. annually if capacity less than 90% Reference FIST Volume 3-6. Monthly. Table 4 FIST Volume 3-6. compare charger meter with digital voltmeter.5 Maintenance Schedule – Battery Chargers Maintenance or Test Preventive maintenance Recommended Interval Dependent on charger type and manufacturer’s recommendations Annually Reference FIST Volume 3-6 Manufacturer’s instruction manual NFPA 70B 20.17 Manufacturer’s instruction manual 4.17 Infrared scan cables and connections if visible 5.4. retorque to specifications 5 years. Table 4 Maintenance or Test Visual inspection Battery float voltage Temperature Intercell connection retorque Capacity testing Safety equipment inspection Infrared scan cells and connections Battery monitoring system FIST Volume 3-6. test all wash devices and inspect all safety IEEE 1106-1995 equipment Annually According to manufacturer’s recommendations NFPA 70B 20. check pilot cell with digital voltmeter Semi-annually. Table 4 FIST Volume 3-6. Bushing maintenance is usually conducted at the same time maintenance is performed on the circuit breaker or transformer. 5. Table 4 FIST Volume 3-6. check fluid levels Shift. 14 . Table 4 IEEE 1106-1995 FIST Volume 3-6. Quarterly. 6.1 Buswork. while system is loaded if possible Reference Doble M4000 Instruction Manual NFPA 70B. and Insulators General Buswork conducts current from one part of the powerplant or switchyard to another. Standoff buswork insulators provide isolation of “live” power circuits from ground and other circuits. 24.2.5. bus maintenance must be conducted de-energized.5 NFPA 70B.3 Table 24. individual insulators Infrared scan. 6. Check and clean enclosures Hipot (to ground and between phases) or Doble Annually 3-6 years Ambient dependent NFPA 70B.5.2 Maintenance Schedule for Bushings Refer to the circuit breaker and transformer maintenance sections of this document for bushing maintenance requirements. Hipot or Megger®.2 NFPA 70B. while loaded if possible Annually 6. 24. 20. Buswork is usually constructed of flat or round copper or aluminum busbar and can be either isolated-phase or nonsegregated. Enclosures.2. 24. Check and tighten connections.6.2 NFPA 70B. Failure of insulators will cause a power system fault and a forced outage.17 Infrared scan. 6.2 Maintenance Schedule for Buswork and Enclosures 5-15 Kilovolts (kV) Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 NFPA 70B.2 above Annually Maintenance or Test Doble.2 IEEE 27 NFPA 70B. 20. 24.5. 20.9. Except for infrared scanning.3 Maintenance Schedule for Buswork Insulators Recommended Interval Only when problems detected in 6.2.2 External visual inspection.5.5.17 15 . while loaded Annually for oilfilled cables Annually NFPA 70B. When done properly. 10 Reclamation Recommended Practice Maintenance or Test Review equipment ratings DC Hipot test (stepped or ramped voltage method) Oil tests (dissolved gas analysis [DGA]. acidity. 8. color.2(a) Annex Table I.1 Power Cables – Rated 5 kV and Above General High voltage cable conducts power between the powerplant and switchyard. 20.1 Potheads and Stress Cones General Potheads and stress cones provide mechanical support and electrical insulation for cables. 20. 7.7. periodic maintenance tests are justified during the life of the cable to determine whether or not there has been significant insulation deterioration due to operational or environmental conditions. In the case of critical circuits.1.17 8. For assistance in determining appropriate test methods and voltage levels for a specific cable installation.2 Maintenance Schedule for Medium and High Voltage Cables Solid Dielectric and Oil-Filled Recommended Interval 5 years 1-3 years Reference NERC Planning Standard FAC-009-1 FIST Volume 3-1 NFPA 70B. dielectric. The cable may be solid dielectric or oil-filled. 7. maintenance tests can detect problems in cables that are approaching failure without accelerating the deterioration process. Insulating capability of these devices is important to prevent a fault and resulting forced outage. 16 . Direct current Hipot tests effectively reduce inservice failures from faults of the cable or its accessories.6. power factor) Visual inspection and infrared scan.1 IEEE 400 and 62 NFPA 70B.2. de-energize the cable circuit before maintenance. water content.5 Annex H Table H. please contact D-8450 at (303) 445-2300.9. Except for infrared scanning. interfacial tension. oil-filled only Recommended Interval 5 years 3-6 years Reference NERC Planning Standard FAC-009-1 Doble Reference Book on Cables and Accessories Doble Power Factor Test Data Reference Book NFPA 70B. cracks Doble AC loss measurement (hot collar) or DC ramp with cable Visual inspection and infrared scan. 9.8. 20. It is subject to catastrophic explosive failure when not tested on schedule. 10. Circuit Breakers 10.2 Maintenance Schedule for Coupling Capacitors Maintenance or Test Review equipment ratings Doble test. maintenance must be conducted with equipment de-energized.17 Infrared scan. These are static devices requiring relatively little maintenance. while loaded Annually 10.1 General Circuit breakers interrupt electrical current to stop power flow both for switching operations and during fault conditions. while loaded Annually 9. Except for infrared scanning.4 Annex H. 9. 20.2 FIST Volume 3-1 Doble Reference Book on Cables and Accessories NFPA 70B. 17 . This equipment normally is oil-filled and must be checked for oil leaks.2 Maintenance Schedule for Potheads and Stress Cones Recommended Interval Annually 3-6 years Reference NFPA 70B.2.1 Coupling Capacitors General Coupling capacitor/voltage transformers (CCVTs) are instrument transformers which provide a path for communications (traveling over the transmission line) to reach communication and relaying equipment without allowing power system frequency energy to pass.17 Maintenance or Test Visual inspection for leaks. Low voltage air breakers are usually located in motor starter cabinets. and auxiliary power. air blast. Examples are 4160-Vac station service. or SF6 breakers. Extra high voltage (EHV) circuit breakers are not addressed in this FIST volume. 11. 11-2. 125-volts direct current (Vdc). motor control centers.10.1 NFPA 70B. and 480-Vac breakers for control. test fault trip Infrared scan.4F Table I. station service switchgear. These breakers may be air.4 Annex H. These are typically 120-volts alternating current (Vac).1 NFPA 70B. or SF6. 20.1 NFPA 70B.2. High voltage circuit breakers are located in separate breaker enclosures. Molded case breakers in panel boards should not be loaded more than 80% of rating per NFPA 70B.10 FIST 3-16 Annex I. 240-Vac.10 and Table H. Examples are 115-kV and 230-kV breakers located in the switchyard. Table I. air-blast. • • • • Most breaker maintenance (except infrared scanning) must be performed with equipment de-energized.8-kV unit breakers. Feeder and Critical Control and Protection Breakers Maintenance or Test Review equipment ratings Visual inspection Recommended Interval 5 years 3-6 years Reference NERC Planning Standard FAC-009-1 NFPA 70B. These are oil. vacuum. 20. 10. either indoors or outdoors. Table I.95-kV and 13.17 Mechanical operation by hand Test critical breakers with current source 300% of rating. while loaded or immediately thereafter 2 years 3-6 years Annually 18 . These are typically 480 Vac for auxiliary power. protection. 13.4(f) Annex I.• Molded case circuit breakers are usually located in low voltage distribution panels and in control boards. Reference the manufacturer’s instruction books. or similar enclosures.2 Molded Case Breaker Maintenance Schedule. Medium voltage circuit breakers are generally located in station-service metal clad switchgear or in separate enclosures as unit breakers. 20. lube.4. 1-3 years maximum 1-3 years per FIST 3 years maximum Reference NERC Planning Standard FAC-009-1 Manufacturer’s Instruction Book NFPA 70B.4(d) FIST Volume 3-16 NFPA 70B.4 Annex H. this document FIST Volume 3-16 NFPA 70B.1 Per manufacturer’s instructions Per manufacturer’s instructions NFPA 70B Annex H Table H.10 Annex H.4 Medium Voltage (601-15 kV Rated) Air and Air Blast Breaker Maintenance Schedule Maintenance or Test Review equipment ratings Inspection and preventive maintenance.10. 8. test all trips Recommended Interval 5 years 1-3 years Reference NERC Planning Standard FAC-009-1 NFPA 70B. align control mechanism Overcurrent trip settings and testing.3 Low Voltage (600 V and Less [480 V] Draw Out Air Breaker Maintenance Schedule Maintenance or Test Review equipment ratings Preventive maintenance and inspection Recommended Interval 5 years Per manufacturer’s recommendations. clean.4 Annex H Table H.2(e) Annex I. while loaded or immediately thereafter Annually 10.2(e) Manufacturer’s instruction manuals Appendix A.1 NFPA 70B. 8. 8.17 Insulation testing and overcurrent and fault trip settings and testing Visual inspection and infrared scan.6. 20.4 Annex H Table H.2(e) NFPA 70B Doble Field Test Guide NFPA 70B.4(d) Annex Table I. while loaded or immediately thereafter 19 .17 Annually or 2.000 operations (3-year maximum) Per manufacturer’s instructions Per manufacturer’s instructions 3-6 years 3-6 years Annually Contact resistance measurement Breaker timing (Motion analyzer) Either Hipot (to ground and between phases) OR Doble test Visual inspection and infrared scan. 20. 20. adjust. adjust.2 Annex Table I. Chapter 13 Manufacturer’s instruction manuals Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines. clean. Chapter 13 Doble test or AC Hipot (including across open 1 contacts ) and to ground 5 years Infrared scan and visual inspection. lube. Chapter 13 Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines.10.1 Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines.5. 20 . electrical terminals tight Contact resistance measurement. Chapter 13 NFPA 70B. grounds.000 Vac) Vacuum Breaker Maintenance Schedule Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 Manufacturer’s instruction manual Preventive maintenance Per manufacturer’s instruction manual Annually Record meter readings Manufacturer’s instruction manuals Western Area Power Administration (WAPA) Standard Maintenance Guidelines. align control mechanisms 1 Annually Caution: Refer to manufacturer’s instructions regarding safe distances (normally 6 feet or greater) to avoid X-radiation if DC Hipot tests. bolts. 8.5 Medium Voltage (601-15. motion analyzer. Chapter 13 Record operations counter Monthly Check foundation. trip test Annually Per manufacturer’s instructions manual Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines. paint Check external screws. and breaking switches Gas cart maintenance Manufacturer’s instruction manuals Manufacturer’s instruction manuals FIST 5-9. motion analyzer. bolts. latch.1.1 and Section 5. electrical terminals tight Contact resistance test. 5 years 5 years Manufacturer’s instruction manuals Manufacturer’s instruction manuals Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines. grounds. Chapter 13 Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines. bolts.000 operations Per manufacturer’s instruction manuals Manufacturer’s instruction manuals Overhaul disconnect. Chapter 13 Annually 5 years.10. moisture test on gas Verify operation and calibration of temperature and pressure switches and gauges Check lube points.000 operations (more frequent if high current operation) 15 years or 5. Chapter 13 Manufacturer’s instruction manuals WAPA Standard Maintenance Guidelines. compare with tolerances Record operations counter Visual inspection Check foundation.6 Medium and High Voltage SF6 Breaker Maintenance Schedule NOTE: Manufacturer should be contracted to do this maintenance if specifically trained personnel are not available.2 21 . nozzles Recommended Interval 5 years Per manufacturer’s instruction manuals Monthly Reference NERC Planning Standard FAC-009-1 Manufacturer’s instruction manuals Manufacturer’s instruction manuals Monthly Monthly. heater operation. Maintenance or Test Review equipment ratings Preventive maintenance Record gas pressure and temperature. linkages. paint Check external screws. 15 EPRI Guidelines Section 5.000 to 10.000 to 10. linkage. grounding. screws. operating mechanism adjustments Overhaul breaker with new seals. annually. contacts. power factor insulation test. if required by manufacturer 5 years 5 years Manufacturer’s instruction manuals 10 to 15 years or 4. trip test. tightness of terminals. 7 High Voltage (Greater Than [>] 15.Doble test (power factor and dielectric strength) and dissolved gas analysis Test tripping circuits 3-5 years 22 . per manufacturer’s instructions Maintenance or Test Review equipment ratings Preventive maintenance Reference NERC Planning Standard FAC-009-1 Manufacturer’s instruction manuals FIST Volume 3-16 FIST Volume 4-1B. Appendix A FIST Volume 3-16 Doble Reference Book on High Voltage Circuit Breakers NFPA 70B.17 Doble Reference Book on Insulating Liquids and Gasses ANSI C57.104 NFPA 70B FIST 4-1b Infrared scan Insulating oil . FIST Volume 3-16.10. 8.Doble with hot collar Bushing . 20. and Appendix A 2 years. more often if ambient condition requires Annually 3-5 years Contact resistance Breaker timing (Motion analyzer) Bushing . more often if ambient condition requires 3-5 years.cleaning Reclamation Recommended Practice NFPA 70B.6 Doble Bushing Field Test Guide IEEE P62-1995 FIST Volume 3-2 FIST Volume 3-16 Doble Reference Book on High Voltage Circuit Breakers Manufacturer’s instruction manuals FIST Volume 3-16 Manufacturer’s instruction manuals Doble Bushing Field Test Guide Visual inspection Breaker and bushings Breaker and bushings Doble test 3-5 years (6 months to 1 year for suspect bushings) Per manufacturer’s recommendations Per manufacturer’s instructions 3-5 years.000 Vac) Oil Circuit Breaker Maintenance Schedule Recommended Interval 5 years Per manufacturer’s recommendations. Maintenance requirements are given in section 14. Control Circuits 12.Radio Communications Handbook (DM377) Information regarding operation and maintenance of Reclamation communication systems may be found at the Reclamation intranet site: http://intra. control circuits that rarely are used should be functionally tested on a periodic basis.Guidelines 07-01. Reliability of these circuits is paramount. these circuits can become compromised over time through various means: • • • • Modifications and construction work which unintentionally break circuit integrity or introduce wiring errors.Management and Use . Although tested during commissioning. 12. However. Verifying the integrity of the control devices and interconnecting wiring requires a “functional test” of these circuits. Communication Equipment This document does not define maintenance of communication equipment used in power system operation. old age. Department of the Interior .gov/telecom. Failure of individual control and protection devices due to misuse. Functional testing of control circuits may be considered completed in the course of normal plant operation.1 General Control circuits (usually 125 Vdc.usbr. 12.11. 250 Vdc.2 Maintenance Schedule for Control Circuits Recommended Interval 3-6 years Maintenance or Test Functional test control circuits Reference NFPA 70B under specific equipment and Appendix H 23 . Refer to communication system operation and maintenance requirements included in these documents: • • Bureau of Reclamation Radio Communication Systems .Departmental Manual . or inadvertent damage. or 120 Vac) provide the path for all control functions for major equipment in the powerplant. Connections that become loose. Age and deterioration of wiring rendering the system nonfunctional. 3 NFPA 12.1 General Carbon dioxide (CO2) systems provide fire suppression for generator and large motor windings.4.3. 15.4.4. Table 2 FIST Volume 5-2. 15. and electrical control systems.3 NFPA 12. 7-3. Recommended Interval Weekly Semi-annually Maintenance or Test Visual inspection and check gauges Weigh CO2 bottles Reference NFPA 12. 1-11. 13. 15. 1-11. Table 2 Function check electrical controls Operate routing valves Annually Annually and after painting Annually 12 years Any discharged cylinder not hydrostatically tested in past 5 years must be tested prior to refill.2 and Table 10.4.3 FIST Volume 5-12. These systems consist of CO2 storage bottles or tanks. 1-11.5 FIST Volume 5-2. piping and valves.6 FIST Volume 5-2. 12. 6.3 Annually 24 .4. 6. smoke.2 Maintenance Schedule for CO2 Systems Caution: CO2 is dangerous and costly to replace.5 FIST Volume 5-12.3. Take care to avoid inadvertent CO2 discharge during maintenance and testing. 1-11.2 FIST 5-12.4.13.3 NFPA 12.3 FIST Volume 5-12. Table 10.3.4. Annually Overall CO2 system functional test Cylinder discharge and hydrostatic test Visually inspect and functional test CO2 discharge warning beacons and alarms Test heat.3. Maintenance Scheduling for Mechanical Equipment. Table 2 NFPA 72. 7-3. 15. flame detectors NFPA 72.1 NFPA 72. when that FIST volume is revised. Note: Mechanical maintenance recommendations are included in this report but may be moved to FIST Volume 4-1A. 6.2 FIST Volume 5-2. 6. Table 2 FIST Volume 5-2. CO2 Systems 13.3 FIST Volume 5-12. 6. Maintenance Scheduling of Mechanical Equipment. Hoists.1 General Cranes. 3-lines. tripping. Also. 14. Maintaining elevators is important to the convenience and safety of staff. Hoists. Every effort must be made to keep key electrical drawings up to date to avoid risk to equipment and staff.2 Maintenance Schedule for Electrical Drawings Maintenance or Test Key control and protection schematics Key wiring diagrams 1-line. are the most important references for safety and O&M of a facility. especially 1-lines. Key electrical drawings should be accessible to all O&M personnel. and wiring diagrams. control and protection schematics. Elevators must be certified by a State-licensed inspector annually in most States. and elevators is covered in FIST Volume 4-1A.2 Maintenance Schedule for Cranes. Cranes. and the public. controls. hoists. wiring Reference FIST Volume 2-10 FIST Volume 4-1A 15. switching diagrams. hoists. Ideally.14.1 General Electrical drawings. 15. Maintenance of these types of equipment is important to the safety of everyone. Only the electrical components are covered here. elevators must be inspected periodically by a certified elevator inspector. and Elevators 14. and Elevators Mechanical maintenance of cranes. Proper maintenance of cranes and hoists will ensure they are ready for service which will reduce time and cost of maintaining other equipment. Recommended Interval Annually Maintenance or Test Inspect motors. Electrical Drawings 15. these drawings will be kept current with all modifications and replacements to plant equipment. switching diagrams Relay data sheets Recommended Interval Current and available Current and available Current and available Current and available 25 . and elevators are important to operation and maintenance of the facility. visitors. fire pumps. 16.1 General Engine generators are critical systems at powerplants. Engine Generators 17. They must be maintained and tested regularly to ensure they will perform as expected. 5. Powerplant critical loads such as sump pumps. Emergency Lighting 16.9.16. dams.2 Maintenance Schedule for Emergency Lighting Recommended Interval Per manufacturer’s recommendation Monthly (30 seconds) Annually (1½ hours) Maintenance or Test Preventive maintenance Reference Manufacturer’s instruction manuals Functional test Functional test NFPA 101. and other waterrelated facilities.3 17. 26 .1 General Reliable plant emergency lighting is essential for personnel safety.9. Spillway or outlet gates/valves may need to be operated for water release purposes with engine generator power.3 NFPA 101. Engine generators provide essential power to supply critical loads in the event of loss of normal power source. and battery chargers also are dependent on reliable power. 5. Manufacturer and NFPA standards should be followed. Engine generators also may be used to power unit auxiliaries and the generator excitation system for blackstart generators assigned to restore the power system after a blackout. many facilities start and run the engine generator weekly. and form POM-400 for complete inspection. At least once every 36-48 months At least monthly 2 8. NFPA 110. In addition.3 Maintenance See Manufacturer’s instruction books.4. per manufacturers’ recommendations.8 and 4.4. and other engine problems that can occur with unloaded exercising.2 Maintenance Schedule for Engine Generators NFPA 110 Reference 8.4.4.1 POM Form 400 Component All Emergency Power Standby Systems (EPSS) components EPSS Inspect Requirement Frequency Weekly Operated at available load for assigned class duration or minimum of 4 hours. Exercised for a minimum of 1 30 minutes (including automatic cold start) by: (1) Running at operating temperature conditions and at not less than 30% of the nameplate kilowatt rating. or (2) Loading that maintains the minimum exhaust gas temperatures as recommended by the manufacturer.3. 27 .4. both directions Exercised manually Weekly 8.6 Load exercising at normal operating temperature is important because it prevents accumulation of carbon particles. Testing and maintenance records for engine generators should be maintained on site.1(a) Generator sets 8.17. Operated electrically.6 Transfer switch Monthly 8. condensed water and acids in the exhaust system. and maintenance requirements.2 Table 4. unburned fuel. 2 17. testing. lube oil.2 Generator set battery Inspected and maintained in full compliance with manufacturer’s recommendations.5 Circuit breakers 1 Annually 8. 28. PEB No. requiring specialized training and unique equipment as well as knowledge of current power system stability requirements. However. transformers.g. Maintenance or Test Preventive maintenance Recommended Interval Per manufacturer’s recommendations 5 years Reference Manufacturer’s instruction manuals Automatic voltage regulator (AVR) and power system stabilizer (PSS) performance testing Contact the Controls Team of the Hydroelectric Research and Technical Services Group. Excitation systems may be rotating or static. protective relays. 303-445-2309 Infrared scan Western Electricity Coordinating Council Controls Working Group (WG) Recommendations Policy Annually Reclamation Recommended Practice 28 . D-8450. excitation system manufacturer maintenance requirements supersede requirements specified in these sections. circuit breakers. It is recommended that qualified staff in the Hydroelectric Research and Technical Services Group (D-8450) perform these tests. 18. annunciators. Automatic voltage regulator performance testing (“alignment”) is a specialty. and buswork) may require maintenance similar to that described in like sections of this document.18. Exciters and Voltage Regulators 18.2 Maintenance Schedule for Exciters and Voltage Regulators Some components of excitation systems (e.1 General Exciters and voltage regulators comprise excitation systems which provide appropriate DC excitation for the field of generators and synchronous motors.. Fire Detection. and Alarm Systems 19.2 Maintenance Schedule for Fire Detection.staffed facility Quarterly . They are crucial to safety of personnel and the public. Fuses 20. primary power supply) Visual inspection .functional test Visual inspection of detection and control equipment (fuses.unstaffed facility Annually .19. Reference the latest version of the standard for the latest requirements. 29 . 19. 7 NFPA 72. 7-3.1 General Fuses provide power and control circuit protection by interrupting current under certain overload and fault conditions.1 Monthly Monthly Annually Per NFPA recommendations Annually unrolled and inspected Annually (site specific) NFPA 72.1 General Fire detection and alarm systems provide indication and warning of fire in the facility. interfaces. 7-3. Fire Fighting Equipment.1 NFPA 72.batteries Lead acid battery 30-minute discharge and load voltage test Ni Cad battery 30-minute discharge and load voltage test Other maintenance Fire hoses Fire extinguisher maintenance 1 Reference NFPA 72.staffed facility Weekly . 20. Correct operation may also minimize damage to equipment by an early response. lamps. 7-3. light emitting diodes.1 NFPA 72.1 NFPA 72 1 NFPA 72 7 is revised regularly.1 NFPA 72. Fire Fighting Equipment.1 NFPA 72. 7-3. and requirements change frequently. 7-3.unstaffed facility Maintenance or Test All circuits . Regular maintenance of systems in unstaffed facilities is particularly important because O&M staff are not usually present to detect problems. and Alarm Systems Recommended Interval Annually . 7-3. Generators and Large Motors 21. Generators and large motors included in this section are synchronous machines performing the primary function of the power or pumping plant. or it may require checking with an ohmmeter. 20.1 Remove. inspect.3 Annex H.2j Annex I.Maintenance Schedules and Records IEEE Standard (Std. etc.) 432-1992. 15 NFPA 70B. some fuse operation cannot be detected remotely and should be assessed by regular maintenance. Guide for Insulation Maintenance for Rotating Electric Machinery (5 horsepower [hp] to 10. Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 NFPA 70B. Loss of meter indication or control circuit operation may indicate a blown (open) fuse. Large motors drive pumps to move water. Testing Solid Insulation of Electrical Equipment Power O&M Bulletin No. 3-6 years Annually NFPA 70B. 19 . Small motors are covered in section 24. while loaded or immediately thereafter. and check Check fuse mounting clips. It may be as simple as looking for the “fuse operated” indicator on the fuse. 15. Visual inspection and infrared scan.” 21.2 References and Standards Maintenance references and standards from which the recommendations are drawn are numerous: • • • • Manufacturers instruction books FIST Volume 3-1.000 hp) 30 .17 Annex H 21.20.1 General Generators produce electrical energy from mechanical power transmitted from the turbine. “Motors.2 Maintenance Schedule for Fuses Some fuse failures are self evident. Other fuses that are critical to equipment operation may be monitored and their opening alarmed. However. Failure to do so may result in more significant failure leading to an outage.2. Volume 1. Power Plant Electrical Reference Series. IEEE Std. Maintenance or Test Preventive maintenance and inspections Recommended Interval No standard recommended interval. thereafter. U. 3 to 5 years and after prolonged maintenance outage. Also. Recommended Practice for Insulation Testing of Large AC Rotating Machinery with High Direct Voltage IEEE Std. Nonroutine thereafter but may be used to verify insulation integrity before and/or after stator winding repair. Kerszenbaum Test Procedure for Synchronous Machines. during major maintenance outages but not to exceed 5 years.AC Hipot test At factory and as an acceptance test.3 Maintenance Schedule for Generators and Large Motors Note: See Appendix B in this document. Machine specific PM according to site operating conditions. Nonroutine.• • • • • • • • IEEE Std.high voltage DC ramp test Stator winding .partial discharge measurements (on line monitoring with partial discharge equipment) 31 . During 1-.S. Stator winding . Performed if problems are suspected. 43-2000. 2½-. 95-1997. I. 4921974 21. IEEE 115-1983 Guide for Operation and Maintenance of Hydrogenerators. Electric Power Research Institute Electric Generators. Recommended Practice for Testing Insulation Resistance of Rotating Machinery Conditions Rating Procedures/Condition Indicator for Hydropower Equipment.physical inspection Stator winding . Army Corps of Engineers Handbook to Assess the Insulation Condition of Large Rotating Machines. EPRI Inspection of Large Synchronous Machines. see Appendix B. and 5-year warranty inspections. Performed in lieu of HVDC ramp test Stator winding . Volume 16.insulation resistance polarization index (Megger®) Stator winding . AC pole drop test Thrust and upper guide bearing insulation test 22. Performed when deterioration detected. 2½-. New digital governors substitute digital control circuits for analog electronic controls of older electrohydraulic governors. and 5-year warranty inspections. During 1-. 2½-. Governors 22. Nonroutine. Stator winding . and 5-year warranty inspections. Performed when deterioration is suspected.ozone measurement Stator winding . Governors may be mechanical type or electrohydraulic type having electronic controls. Nonroutine. thereafter. during major maintenance outages but not to exceed 5 years.insulation resistance polarization (Megger®) Rotor . Mechanical maintenance requirements for all types of governors are identified in FIST Volume 4-1A. Nonroutine. Nonroutine. thereafter.physical inspection Stator core . Nonroutine.wedge tightness measurements Stator winding . Should be performed prior to rewind or if core has been damaged. Performed when deterioration is suspected.physical inspection Rotor .black out test Nonroutine. During major maintenance outages but not to exceed 5 years.1 General Governors control generator power and frequency output by regulating water flow to the turbine. Mechanical Governors for Hydraulic Units. The electrical maintenance schedule below supplements these mechanical maintenance requirements. May be performed in conjunction with other generator condition tests. Annually per FIST Volume 5-11. 32 . performed after rotor is removed (particularly if unit in operation for 20-25 years without rewedging). Maintenance Scheduling for Mechanical Equipment.Continued Stator winding . Mechanical governor maintenance is fully described in FIST Volume 2-3. During 1-. Performed when deterioration is suspected.core magnetizing test Rotor .power factor measurements (Doble) Stator core . 2 Maintenance Schedule for Governors Recommended Interval Per manufacturer’s recommendations 5 years Maintenance or Test Preventive maintenance Reference Manufacturer’s instruction manuals Reclamation Recommended Practice Control system alignment 23. They are usually induction motors and are generally less than 500 hp but may be somewhat larger. Motors (< 500 hp) 24. Ground Connections 23. loose connections. valves. and mechanical damage. Critical motors should routinely be tested.1 General Motors of this type drive pumps. 23.1 General Equipment grounding is an essential part of protecting staff and equipment from high potential caused by electrical faults. Equipment grounding conductors are subject to failure due to corrosion.2 Maintenance Schedule for Ground Connections in Substations/Switchyards Recommended Interval Annually Maintenance or Test Visual inspection. tighten connectors Reference PEB No. Grounding may also be compromised during equipment addition and removal or other construction-type activities. 33 . gates. Periodically verifying grounding system integrity is an important maintenance activity.22. 26 24. and fans. 24.2 Maintenance Schedule for Motors Recommended Interval Annually Maintenance or Test Insulation resistance (Megger®) Infrared scan Reference FIST Volume 3-4. test every 2 years test Gloves.269J(iii) IEEE Std.7 FIST Volume 5-1 FIST Volume 5-1 Safety ground .millivolt drop test Annually and before each use Annually Inspect before Hot stick cleaning. inspection. 978 Manufacturer’s instruction manuals NFPA 70E.5 25.2 Annually NFPA 70B. and electrical each use.1 General Personal protective equipment is used by maintenance workers to provide protection from hazardous electrical energy.visual inspection Safety ground . 130. 2.7 IEEE 978 34 . Personal Protective Equipment 25. 20-17. 130. Integrity of this equipment is paramount.2 Maintenance Schedule for Personal Protective Equipment Hot Line Tools Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 NFPA 70E. so maintenance should be scheduled and accomplished similar to equipment maintenance. 25. sleeves. blankets tests Annually OSHA 1910. Electrical protective relays are calibrated with settings derived from system fault and load studies. electrical power systems change as new generation and transmission lines are added or modified. Calibration: This process usually includes removal of the relay from service to a test environment. Initial settings are provided when relays are installed or replaced.” Protective relays monitor critical electrical and mechanical quantities and initiate emergency shutdown whenever they detect out-of-limits conditions. Fault and load studies and relay settings are provided by the Electrical Design Group (D-8440) at 303-445-2850.1 General Section 11. Protective relays operate into protection circuits to accomplish the desired protective action. protection circuit integrity may be compromised by construction. This may mean that relay settings are no longer appropriate. This can be accomplished as part of the calibration procedure in most cases. and to the equipment itself.26. However. Calibration of electro-mechanical relays is recommended frequently since operating mechanisms can wear and get out of adjustment.4 of the Western Electricity Coordinating Council (WECC) Minimum Operating Reliability Criteria requires that: “Each system shall provide for periodic testing of protective systems and remedial action schemes which impact the reliability and security of the interconnected system operation. Relay Functional Test: This process verifies that the protective outputs of the relay (e. or inadvertent damage. Calibration of solid-state and microprocessor-based relays is recommended less frequently since there are fewer ways for them to get out of calibration. Relays and Protection Circuits 26. Outdated relay settings can be hazardous to personnel. Field-initiated changes to relay settings should be verified by this group. Therefore. Calibration and maintenance recommendations differ from type to type because of their different design and operating features. modifications. Protective relays currently in use in Reclamation include electro-mechanical.. Similar to control circuits. A compromised protection circuit may not provide the system and plant protection desired. it is necessary to periodically conduct a fault and load study and review protective relay settings to ensure safe and reliable operation. deterioration. Periodic functional testing is recommended to ensure the integrity of protection circuits. Injecting current and/or voltage into the relay and observing the response according to the manufacturer’s test procedure verifies the recommended settings. Protective relays must operate correctly when abnormal conditions require and must not operate at any other time. and microprocessor-based packages. contact closures) actually operate as intended. but relay functional testing should be verified according to the maintenance schedule.g. solid-state. to the integrity of the powerplant and power system. 35 . Activate the lockout relay from each protective device. If the light is not lit. With lockout relays reset. Protective circuit functional testing is accomplished as follows: • • • • Conduct a Job Hazard Analysis. Caution: Do not forget to reconnect the trip bus to the lockout relay when testing is complete. These lights should be lit when the lockout relay is in the “Reset” position or when the breaker is closed. However.. Verify that circuit breakers actually tripped (or other protective action occurred) from the lockout relay action. Where functional testing of ALL protection circuits is unfeasible. This requires actually operating the entire circuit to verify correct operation of all components. initiate lockout relay trip with the protective device contact.3 Verify the lockout relay actually tripped from the protective relay action.g. it may be desirable to lift the trip bus from the lockout relay so as not to repeatedly trigger the lockout—a meter may be substituted to verify contact initiation. 3 36 . The ideal functional test is to actually change input quantities (e. Verify that testing will not disrupt normal operation or endanger staff or equipment. • It is recommended that the protective device actually be operated where possible for best assurance. Reclamation standard design for lockout relay and circuit breaker control circuits includes the use of the red position/coil status indicator light to monitor the continuity of the circuit through the trip coil. this may indicate a problem with the coil integrity which should be addressed immediately. it may be necessary to simulate contact operation with a “jumper” when device activation is not possible. testing of the most critical protection circuits and devices is still recommended. instrument transformer secondary injection) to the protective device to thoroughly test the entire protection path.Protection Circuit Functional Testing: This process verifies that the entire protective “trip path” from protective relay through circuit breakers (or other protective equipment) is intact and functional. After the first full test of lockout relay and breakers. 1 Per manufacturer’s instructions Fist 3-8 WECC Std.4 NFPA 70B. 11.26. 6 and Manufacturer’s instructions Electro-mechanical relays Calibration and functional testing Upon commissioning and every 2 years Solid-state relays Calibration and functional testing Upon commissioning 1 year after commissioning and every 3 years Microprocessor relays Calibration and functional testing Upon commissioning 1 year after commissioning and every 8-10 years Protection circuit functional test. 1 37 .4 Reclamation Recommended Practice Per manufacturer’s instructions Fist 3-8 WECC Std.7 and 20. Otherwise. check each visit to the plant.10. 11.7 and 20. 6 Reclamation Recommended Practice Power Equipment Bulletin No.9.3 Annex Table I.9.1 Per manufacturer’s instructions Fist 3-8 WECC Std. in conjunction with daily operator control board checks.3 Annex Table I.4(c) Manufacturer’s instruction manuals PEB No. 8.4 FIST Volume 3-8 NFPA 70B Annex Table H.10.2 Maintenance Schedule for Relays and Protection Circuits Recommended Interval 5 years Maintenance or Test Fault/load study and recalculate settings Reference Reclamation Recommended Practice NERC FAC-009-1 NFPA 70B. including lockout relays Immediately upon installation and/or upon any changes in wiring and every 3-6 years Check red light lit for lockout relay and circuit breaker coil continuity Lockout relays Cleaning and lubrication Daily 1 5 years In staffed plants. 11. 8. and Office of Management and Budget (OMB) Circular A-130. real-time control systems for power and water operations. Periodic audits. Appendix III Presidential Decision Directive 63 Public Law (P. Appendix III. and facility equipment. 1998. Security of Federal Automated Resources. SCADA Systems 27. circuits that are infrequently used may require periodic functional testing to ensure they will be operational when the need arises. 1996.training Reference Manufacturer’s instruction manuals Reclamation Recommended Practice Reclamation Recommended Practice OMB Circular A-130.1 General Security systems at powerplants are critical for protection of Reclamation personnel. Since these systems are in operation continuously and are in many ways self-diagnosing. Security Systems 28. Most security systems are site 38 .1 General Supervisory Control and Data Acquisition (SCADA) systems are computer-based. the public.L. Critical Infrastructure Protection Plans (CIPP).2 Maintenance Schedule for SCADA Systems Recommended Interval Per manufacturer’s recommendations 3-6 years Annually 3 years 2 years Annually Maintenance or Test Preventive maintenance Functional test circuits Failure mode tests Security . Security requirements affecting SCADA are dictated by documents such as Presidential Decision Directive 63: Critical Infrastructure Protection. However. regular maintenance and testing is not necessary except as recommended by the manufacturer. February 8.27.) 100-235.audit Security . 27. Computer Security Act of 1987 Reclamation Recommended Practice Uninterruptible power supply test Annually 28.CIPP updated Security . May 22. and regularly scheduled security training are important requirements of SCADA security. Appendix C NFPA 70B. Examples of transduced data include: • • Bearing oil level or temperature read by a meter or scanning equipment Megawatt or megavars as input to the SCADA system 39 . Accuracy of transduced signals is important to alarm and control functions. (See section 20 on fuses).2 Maintenance Schedule for Disconnect Switches Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 Manufacturer’s instruction manuals Appendix C NFPA 70B. facilitating safety during maintenance procedures.1 General Transducers convert data collected in one format into electrical signals used by meters and computerized monitoring and control systems. 20. Disconnect switches may be manually or motor operated and. card key systems. while loaded Annually 30. and other types of equipment. gates. thus. gate controls. receivers. Disconnect – Medium and High Voltage 29.2(f) FIST Volume 4-1B. in some cases. may integrate fuse protection. it is imperative that personnel at each plant understand and follow manufacturers’ instructions for maintenance and testing the particular equipment installed.specific including many different manufacturers of cameras.17 Preventive maintenance Per manufacturer’s recommendations and per Appendix C Semi-annual Visual inspection Infrared scan. 8.7 Annex H.1 General When open. 29. disconnect switches permit isolation of other power system components. 29. Therefore. Transducers/Meters 30. Switches. 31. 12. Transformer Diagnostics NFPA 70B . Transformer reliability is essential to the continued delivery of the facility’s services.30. and sometimes record. Some meters also transmit stored data to Supervisory Control and Data Acquisition (SCADA) or other systems. electrical and mechanical quantities for operator information.7 31.2 References and Standards Maintenance references and standards from which the recommendations are drawn are numerous: • • • • • • • Manufacturers’ instruction books Doble Transformer Maintenance and Test Guide IEEE Std. Accuracy of meter indication is important to ensure correct power and water systems operation. and Diagnostics (Reclamation manual) 40 .9.Recommended Practices for Electrical Equipment Maintenance Transformers: Basics. 62-1995 FIST Volume 3-30. Maintenance.2 Maintenance Schedule for Transducers Maintenance or Test Calibration Recommended Interval 3-5 years Reference: NFPA 70B.4 30.3 Maintenance Schedule for Meters Meters indicate.1 General Transformers convert electrical power from one voltage level to another. Maintenance or Test Calibration/inspection Recommended Interval 3-5 years with transducers and when problems are suspected Reference NFPA 70 B. Transformers 31. 8. Transformer Maintenance FIST Volume 3-31. instrument transformers (particularly current transformers) may become overburdened with the addition of more devices in the secondary circuit. while current transformers have output in the 2..2 Maintenance Schedule for Station and Distribution Transformers Maintenance or Test Review equipment ratings Infrared scan.5.3 Station/Distribution Transformers Under 500 kVA4 31. 500-kV switchyard at Grand Coulee).g. Periodically. Typically. measuring secondary burden and comparing it to the transformer rating will indicate if this is a problem. 41 .8 31. 31.17 FIST Volume 3-30 Reclamation Recommended Practice FIST Volume 3-30 NFPA 70B.240/120-Vac transformer that supplies power to auxiliary lighting panels.1 General Instrument transformers convert power system level voltages and current to levels safe to feed meters and other low voltage and current devices.to 5-ampere range.2. This may lead to saturation during a fault which may cause the relay to misoperate. Over the course of time.3. Voltage transformers may be integral to other equipment or stand alone.4. 20. Instrument transformers that are oil-filled will fail catastrophically and cause hazards to workers if not maintained properly.1 General Station and distribution transformers generally operate at relatively low voltages and power ratings. while loaded Doble test if oil-filled Dissolved gas analysis if oil-filled Recommended Interval 5 years Annually 3-6 years Annually Reference NERC Planning Standard FAC-009-1 NFPA 70B. 9. 4 kVA = kilovoltampere.31. transformers) but occasionally may be stand alone (e.4 Instrument Transformers 31. They provide step-down power to supply plant auxiliary loads—for example.3. Voltage or potential transformers generally have output in the 240/120-Vac range. Instrument transformer secondary wiring always should be checked for integrity after any work that may have disrupted these circuits. current transformers are integral to other equipment (circuit breakers. Any oil leak should trigger immediate Doble testing and replacement planning. a 480 . 2(c) FIST Volume 3-30 NFPA 70B.2(c) FIST Volume 3-30 NFPA 70B. 9.2(c) NFPA 70B.1 General Dry-type power transformers are air cooled. having no liquid insulation.5.2. 9. Typical applications include station service and excitation system transformers.3 Annex H.3 Annex H.9 and 20.2(c) FIST Volume 3-30 NFPA 70B. 9.2(c) NFPA 70B.9 Maintenance or Test Review equipment ratings Infrared scan Temperature alarm check Visual inspection/cleaning Annually Check fan operation Annually Clean fans and filters Annually Turns ratio test 3-6 years or if problems are suspected 3-6 years or when problem is suspected Megger® windings or Hipot 42 . 20.2(c) FIST Volume 3-30 NFPA 70B. 20.5 Dry-Type Power Transformers – 500 kVA and Larger 31.17 Maintenance or Test Review equipment ratings Burden measurements Doble test if oil-filled Visual inspection Infrared scan 31. 9.11 NFPA 70B Annex H. 9.5.2 Maintenance Schedule for Instrument Transformers Recommended Interval 5 years 5 years 5 years Annually Annually Reference NERC Planning Standard FIST Volume 3-8 Reclamation Recommended Practice Reclamation Recommended Practice NFPA 70B.31. 31.3 Annex H.4.17 FIST Volume 3-30 NFPA 70B. 9. 20.2 Maintenance Schedule for Dry-Type Power Transformers Recommended Interval 5 years Annually Annually Reference NERC Planning Standard FAC-009-1 NFPA 70B.3 Annex H.3 Annex H. 20.6.2 FIST Volume 3-30 NFPA 70B.DGA.Megger® test Leakage reactance. 31. These transformers may be two-winding or more and include autotransformers.Doble test Quarterly and 3-5 years Weekly 3-5 years 3-5 years (6 months to 1 year for suspect bushings) Annually Annually after first year of operation If DGA indicates Transformer and bushings .6 Oil-Filled Power Transformers 31. physical.2 Annex H.2(b) FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-31 FIST Volume 3-30 FIST Volume 3-30 Maintenance or Test Review equipment ratings Preventive maintenance Transformer physical inspection Bushings . 9. 6.1. Turns Ratio tests. generator step-up transformers.infrared scan Insulating oil .9. and chemical tests Core .6.31. SFRA test Cooling fans . 9.2.check oil level Bushings .4 FIST Volume 3-5 FIST Volume 3-30 IEEE P62-1995.inspect and test Oil pumps and motors inspect and test If problems are indicated by other tests Annually Annually 43 .1 General Oil-filled transformers generally deliver power to and from the main units of the facility—for example. These transformers are generally located outside the building in a transformer bay or in a switchyard.5 NFPA 70B. 9.2 Annex H FIST Volume 3-30 Doble Bushing Field Test Guide IEEE P62-1995 FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-2 Doble Bushing Field Test Guide IEEE P62-1995.17 FIST Volume 3-30 NFPA 70B.cleaning Transformer and bushings . 6.visual inspection Bushings .2 Maintenance Schedule for Oil-Filled Power Transformers Recommended Interval 5 years Per manufacturer’s recommendations Annually Reference NERC Planning Standard FAC-009-1 Manufacturer’s instruction manuals FIST Volume 3-30 NFPA 70B. rails.” and Edison Electric Institute’s “Fire Protection for Transformers. 32.3 FIST Volume 3-32 See manufacturer’s instruction 44 .Continued Heat exchangers inspect Conservator and bladder . Based on Reclamation’s past practice. Transformer Fire Suppression Systems 32. 8.inspect Top oil and winding thermometers Oil level indicator operation Pressure relief device Annually 3-5 years Annually inspect and infrared scan 3-5 years calibrate 3-5 years Annually inspect and perform function test 3-5 years check oil leaks Annually inspect and perform function test 3-5 years test per manufacturer’s recommendations Annually inspect and perform function test 3-5 years FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-30 FIST Volume 3-30 Sudden pressure relay Manufacturer’s instructions FIST Volume 3-30 Buchholz relay Inspect foundation. trucks Manufacturer’s instructions FIST Volume 3-30 FIST Volume 3-30 POM 19 32.” Reclamation requires fire suppression for mineral oil-filled GSU transformers.1 General Reclamation generator step-up (GSU) transformers normally contain thousands of gallons of flammable transformer oil. on NFPA 851 “Fire Protection for Hydroelectric Generating Plants.2 Maintenance Schedule for Transformer Fire Suppression Systems Recommended Interval Annually run pump with water flow Maintenance Maintenance or Test Fire pumps Reference NFPA 25.3. 3 NFPA 70B.1 See NFPA 25 Table 12. Table 8. Table 8.1 General Transmission lines carry electrical power between the facility and the power system.5. However. “Circuit Breakers” Annually See NFPA 25 Table 10. 33.3 NFPA 72-10 FIST Volume 3-32 NFPA table 8.1 See NFPA 750.Continued All systems Circuit breakers All systems Test alarms and automatic starting All systems Visual inspection of electrical system Water spray fixed system (nozzles fixed) Valves and valve components Water mist system Manually operate Monthly and visual inspection 6 months NFPA 25.17 Visual inspection with binoculars Infrared scan Semi-annually Annually 45 .2 Maintenance Schedule for Transmission Lines Recommended Interval 5 years Maintenance or Test Review equipment ratings Reference NERC Planning Standard FAC-009-1 NFPA 70B Annex H. Table 13.3.3.5. “Circuit Breakers” 33. 20.2.2 and Table 13.5.4 See section 10. inspection of transmission line segments entering switchyards is recommended. Transmission Lines 33.4 FIST 3-32 NFPA 25 FIST Volume 3-32 NFPA 25 FIST Volume 3-32 NFPA 750 FIST Volume 3-32 See section 10. “Circuit Breakers” Manually operate breakers and test all circuit breaker trips according to section 10. Reclamation maintains relatively few transmission lines.3 FIST Volume 3-32 NFPA 25. 34. 2005 WECC Policy dated April 23. 2004 Reclamation Policy Memo dated April 28. 34. They must be able to self-start without any source of offsite electrical power and maintain adequate voltage and frequency while energizing isolated transmission facilities and auxiliary loads of other generators.2 Testing Schedule for Blackstart Generators Recommended Interval 5 years 5 years Maintenance or Test Review equipment ratings Demonstrate through simulation or test that the unit can perform its intended function as required by the system restoration plan Each unit tested to verify it can start and operate without being connected to the system Reference NERC Planning Standard FAC-009-1 WECC and NERC Combined Planning Standard IV Part A WECC Policy dated April 23. 2005 See POM Form 401 Annually 46 . 2004 Reclamation Policy Memo dated April 28.1 General Upon complete loss of the power system (blackout). Blackstart Generators 34. Initiating (main unit) generators are referred to as system blackstart generators and are designated as such in system blackstart restoration plans. it will be necessary to establish initial generation and begin system restoration at select powerplants. Appendix A AIR AND OIL CIRCUIT BREAKER PREVENTIVE MAINTENANCE . . Appendix A AIR AND OIL CIRCUIT BREAKER PREVENTIVE MAINTENANCE Adapted from Power O&M Bulletin No. Inspect oil valves and plugs and stop oil leaks. Inspect underside of cover for moisture and rust. See that oil drain valves that can be operated without wrenches are plugged or locked to prevent unauthorized opening.” in the body of this FIST volume. Section 10 NOTE: Unless the maintenance interval is specified. Oil Levels and Gauges Daily or Weekly – Check oil level in gauges of the tanks and oil-filled bushings. Drain out and replace bushing oil if dirty or discolored. 19 – Maintenance Schedules and Records – October 1965. Foundation • Check foundation for cracks and settling. For other maintenance requirements. Breathers and Vents Daily or Weekly – Check for external obstructions to breakers and vents. Oil Valves and Plugs • Check condition of paint and repaint as necessary. conduct preventive maintenance annually (indicated by •) or as the equipment becomes available during an outage. • Check to see that screens and baffles in vents or breathers are not obstructed or broken. Frame and Tanks Daily or Weekly – Check for oil leaks and note tank temperature by touch. • Clean dirty gauge glasses and connections into tank. A shift of the breaker tanks may break bushings or cause misalignment of contacts or binding of operating mechanism. and clean and repaint as necessary. Tighten bolts. see section 10. 47 . Clean exterior of tanks. “Circuit Breakers. Check tank liners and interphase barriers. Replenish oil if below normal. Experience will tell how many faults can 48 . It is necessary to carefully remove only the projecting beads. loose or overheating connections. Check oil sample from bottom of bushing for dielectric strength and dissolved gas analysis (DGA) and presence of water and dirt which may be entering at top. or Hipot. Check insulation resistance with contacts closed with Doble test set. birds’ nests. Megger®. Main Contacts • Remove the tanks or drain out oil so that the contacts can be inspected. in or near connecting buswork. liquid turtle wax. latches. Inspect ground cable to see that it is not loose or broken. Check condition of enclosing cabinets including hinges. • Clean porcelain with water. Tighten bolts. Bushings or Insulators Quarterly – Check for chipped or broken porcelain. and loose or broken frame ground connections. Refinish contact surfaces if they have been overheating. oil level and oil or compound leaks. if rough. including tap connections into bushing. Check contact drop with “ducter” or by direct current millivolt drop with a micro-ohm meter. Pits in a flat. Inspect gaskets for leaks. locks. or other suitable cleaner. Replace or replenish oil if necessary. Tighten connections. etc. with a fine file. smooth surface are not objectionable. Check and clean interior at least once every 5 years. Main Terminals and Ground Connections Daily or Weekly – Check for presence of foreign materials. and paint. • Tighten all bus and ground connections and inspect for heating. Repair chipped spots by painting with lacquer such as 1201 glyptal. Frequency of breaker contact maintenance should be based on number and severity of faults interrupted rather than a definite time period. Check insulation resistance of wiring with devices connected. excessive dirt film. Dress contacts.Panels and Cabinets • Check air circuit breaker or other panels of insulation material for cracks and cleanliness. door gaskets. Check ratio and phase-angle adjustments of potential transformers if changes have been made in secondary connections or burden. Bushing Current Transformers and Potential Devices • Check tap settings and adjustments at terminal board to see that they agree with diagrams. Only after breakers have field experience should the inspection periods be extended. F. 49 . breaks. bends. breaks. C. If recurring troubles are found on a certain type of breaker. All new breakers must have a complete inspection at the end of 1 year. Breakers interrupting a large number of faults should be given special attention to determine whether or not early internal inspection is required. weakening. the inspection schedules should be shortened until trouble is eliminated. Data should be kept on each breaker to guide future maintenance. de-ion grids. B. Contact Pressure Springs • Check springs for loss of temper. Flexible Shunts • Check flexible shunts at contact hinges for overheating and fraying. The following factors should be established before intervals between inspections can be extended: A. Check adequacy of guides. D. Air. Breakers used on special applications. or Oil Blowout Devices • Check arc-rupturing blowout coils. such as capacitor and reactor switching. When oscillographs indicate abnormal breaker operation. E. or warping. or rust deterioration. Crosshead • Check contact crosshead for misalignment. Inspection schedules might be extended further as oil handling methods. or looseness on lift rod. or other interrupters for proper operation. Lift Rods and Guides • Check contact lift rods for breaks. should be considered separately. oil blast. Magnetic. arc chutes. magnetic circuit. Tighten connections. an immediate inspection of the breaker should be made. methods for determining oil condition. and other improvements are made.be interrupted before contact repairs are necessary. and pulling out at ends. Check solenoid plunger for sticking in guides. Check motor. Wipe off excess oil. After that. keys. and gears with a suitable cleaner. Check latch carefully to see that it is not becoming worn so that it would unlatch from vibration or stick and fail to trip. and misalignment. bearings. Shafts. and gears will act more like a 6. and accumulated grease and oil. binding. Enclosed dust-tight bearings should require less servicing. Closing Solenoid Air Cylinder. etc. • Observe mechanism during several closing operations to see that everything is in proper working order. and Bell Cranks • Check for loose locknuts. and operate breaker several times to work out dirt and old lubricant. Tighten bolts and screws. or Spring Weekly – Visual inspection to see that equipment is in operating condition. dirt. bearings. Check closing springs for proper tension and closing energy. and latches for wear. bent rods. • Clean and relubricate. Wash out bearings. Operating Time • A 2-cycle breaker with dirty or dried out grease in the operating mechanisms. 50 . Drain condensation from air cylinder. setscrews. the operating time will be closer to normal until it has again “rested.Operating Rods. bearings. See that breaker will close with it. Motor. or twisted shafts. Manual Operating Device • See that manual operating lever or jack is kept on hand and in usable condition. • Observe mechanism during several tripping operations to see that everything is in working order. it is important to use lubricant that will not stiffen with cold. Clean moving parts of rust.to 12-cycle breaker the first time it is operated or exercised. In cold climates. Latch and Trip Mechanism Weekly – Visual inspection to see that mechanism is in operating condition.” at which time. pivots. Annually – Check pins. Lubricate with new grease or oil. • Dismantle air cylinder and clean and relubricate. Annually – Check coil resistance and insulation resistance. it will again have unacceptable operating times. See that door gaskets are tight and properly exclude dust and dirt. Dashpots or Snubbers • Check for proper setting and adjust as necessary. Check plunger for sticking in guides. Solenoid Valves Annually – Check for condition of valve seat and refit as necessary. Mechanism Cabinet • Check condition of metal and hardware. snappy action of plunger is obtained. Auxiliary Switches Annually – Check condition of contacts and refinish with fine file if burned or corroded. See that full energy. operating rods. Check resistance and insulation resistance of solenoid coil. • Observe operation during electrical tripping. Position Indicator • See that position indicator or semaphore is properly indicating the breaker position. Check operating rods or levers for loose parts. and levers. 51 . • Check contact springs. • See that the operations counter is properly registering the operations. Certain auxiliary contacts used for special purposes may require close adjustment in this respect. Operation Counter Monthly – Observe and record reading of operation counter. Annually – Check coil and insulation resistance.Tripping Solenoid Weekly – Visual inspection to see that solenoid trip device is in operating condition. • See that moving parts are free to operate. Check closing and opening position with respect to main contacts while breaker is being slowly closed and opened manually. Clean out and replenish liquid in liquid dashpots. Repaint as necessary. Power Supplies and Wiring Weekly – See that all power and control circuit switches are closed and fuses are in place. Oil DGA and Dielectric Tests Annually – Check dielectric strength of the insulating oil in the main tanks and oil-filled bushings. GET-1125. Filter Oil • The necessity for filtering the insulating oil will depend on the results obtained from the oil tests and the amount of carbon in the oil. have a tendency to develop contact heating if left closed for long periods. Operation • Some breakers. References How to Maintain Electric Equipment. Inspect wiring for open circuits. as system operation permits. short circuits. • Check and tighten wiring connections at terminal points. if in poor condition. The oil should be filtered if the dielectric strength is below 25 kilovolts or if there is a noticeable amount of carbon in suspension or in the bottom of the tanks. may reduce contact resistance and heating by wiping the oxide from the contact surfaces. Check insulation resistance of wiring with devices connected. • Check heating elements and replace.Cabinet Lights and Heaters Weekly – Check cabinet heaters and see that they are in service in cold weather. particularly those carrying high values of current. Annually – Inspect fuses or circuit breakers in all power and control supply circuits. Replace burnt-out lamps. and damaged insulation. Testing and Maintenance of High Voltage Bushings 52 . Testing of Solid Insulation of Electrical Equipment FIST Volume 3-2. General Electric Company FIST Volume 3-1. This method also demonstrates that the breaker is in operating condition. Opening and closing breakers several times at intervals. Painting of Transformers and Oil Circuit Breakers FIST Volume 3-16. Maintenance of Power Circuit Breakers FIST Volume 3-17. Replacing Glaze Burned Insulators 53 . Power Circuit Breaker Problems FIST Volume 3-18.FIST Volume 3-7. . Appendix B GENERATIOR AND LARGE MOTOR PREVENTIVE MAINTENANCE . . Section 10 NOTE: Unless the maintenance interval is specified. Foundation. Check and tighten field pole piece clamping bolts. loose. Base. (See FIST Volume 2-2. Frame • Check for cracks and loose or broken parts. Laminations and Pole Pieces • Check for loose laminations and tighten clamping bolts. 19 – Maintenance Schedules and Records – October 1965. conduct preventive maintenance annually (indicated by •) or as the equipment becomes available during an outage. Check field circuit connections and tighten if necessary. (Refer to manufacturer’s instructions or contact the Hydroelectric Research and Technical Services Group at 303-445-2300 for proper torque values. If laminations vibrate and cannot be stopped by tightening clamping bolts.Appendix B GENERATOR AND LARGE MOTOR PREVENTIVE MAINTENANCE Adapted from Power O&M Bulletin No. Check voltage drop across each pole by applying alternating current at the collector rings. Check frame ground connection. force some quick-drying varnish or shellac between the loose laminations while the machine is out of service. Clean and repaint as necessary. or weakened parts. or Support • Check concrete foundation for cracks. Check base or support for broken. This method will show a turn-to-turn short better than using direct current.) Armature or Rotor • Check squirrel-cage rotor bars or amortisseur windings for loose or broken bars or end connections. Rebalance armature or rotor if vibration is objectionable. • 55 . Check pole keys for tightness.) Check overall rotor resistance or impedance. Field Balancing of Large Rotating Machinery. Check and tighten anchor bolts. Check soundabsorbing base for adequacy. Check for damaged laminations at airgap due to rubbing or objects caught in airgap. and connections. Slot Wedges • Check slot wedges and replace loose ones. Tighten bolts. Clean exposed parts of windings thoroughly with a nonflammable solvent using suitable brushes for hard-to-reach places. Check and tighten holding bolts and screws. Wipe commutator or rings if needed. brittle. or dull. Apply lashing if end turns vibrate excessively.Airgap • Check airgap at four quadrature positions and recenter rotor if necessary. or moisture. if necessary. (See FIST Volume 3-1. Check end-turn lashing of alternating current stator coils. or evidence of corona. or eccentric. Windings • Inspect for damaged insulation. Brushes and Brush Rigging • Turn down. Testing Solid Insulation of Electrical Equipment. Check brush spring tension and brush fit. they should not be disturbed. brittleness. Blow out dust with clean. Undercut mica if high. dry air at pressure not exceeding 40 pounds per square inch.) Banding and Lashing • Check wire and string banding on direct current armature windings. the bearings may need replacing if the bottom airgap is appreciably smaller than the top. or polish commutator or collector rings if grooved. Check for insulation deterioration such as tape separation. Reset brush holders if not 56 . Revarnish windings if insulation is becoming hard. Air Fans • Check rotor air fans for fatigue cracks. rough. dirt. On horizontal machines. Have brushes replaced if worn too short. Check insulation with high voltage direct current method. If commutator or rings have a good polish. The use of carbon tetrachloride is not recommended because of the toxic hazard. screws. oil. cracking. stone. Commutator or Collector Rings • Daily – Check commutator or collection rings and brush operation. Tighten coils in slots by rewedging. sludge. Check insulation of insulated bearings. (See FIST Volume 2-4. Lubrication of Powerplant Equipment. Adjust belt or silent chain tension. Clean up carbon or metallic dust. lubrication. Then flush out thoroughly. Couplings. Flush out and renew grease in gearboxes. and Pulleys • See that keys. and relays for correct operation and sticking. Replace or refinish rough bearings. Check alignment between driving and driven machine. Check for shaft currents through bearings on larger machines. circulate a solution of 25% hydrochloric acid and water through the coils until clean. and oil level. and acidity. Replace and sand in new brushes if needed. Check external supply and piping for leaks.properly spaced. and Pressure Gauges and Relays • Check indicators. and filter or replace as necessary. Check calibration if in doubt. Check cooling water flow. Check brush neutral position. Water and Oil Flow. Test bearing cooling coils for leaks by applying air pressure to coils. and coupling bolts are tight. Check end play on horizontal machines. If water scale is present. Use hydrostatic pressure test on air coolers. Inspect bearing oil piping and cooling water piping for leaks. Flush out cooling coils with air and water. Clean external surfaces of coils if practical. Check oil for dirt. Gears. Temperature Indicators and Relays. Check oil film resistance occasionally with machine in operation with ohmmeter of 6 volts or less on thrust bearings provided with test terminals. chains. Shaft and Bearings Daily – Check bearing temperature.) During Shutdown/Inspection – Check bearing clearances. dirty contacts. A pressure of 75 pounds per square inch is recommended. gauges. Check parts of flexible couplings for wear or fatigue. Check shaft for wobble and alignment. Inspect belts. Observe for air bubbles rising in oil and drop in air pressure with supply valve closed or use hydrostatic pressure test. or gears. 57 . Cooling Coils and Air Coolers • Check for water leaks in bearing cooling coils and surface air coolers. setscrews. Recordkeeping Maintain detailed records. If temperature readings begin to rise over 5 degrees Centigrade for the same loading conditions. Field Balancing of Large Rotating Equipment FIST Volume 2-4. General Electric Company FIST Volume 1-4. Generator Thrust-Bearing Insulation and Oil Film Resistance 58 . Testing Solid Insulation of Electrical Equipment FIST Volume 3-3. References How to Maintain Electric Equipment. Electrical Connections for Power Circuits FIST Volume 3-11. tracking armature temperature against generator load. Permissible Loading of Generators and Large Motors FIST Volume 2-2. this may indicate a problem that should be investigated. Lubrication of Powerplant Equipment FIST Volume 3-1. GET-1125. Appendix C DISCONNECT SWITCH PREVENTIVE MAINTENANCE . . replace broken insulators. tighten bolts and screws. Clean and replace as needed. tighten base and cap bolts. Major Maintenance or Overhaul Depending on ambient. Check bolts for manufacturer’s recommended torque. 3 to 6 years. terminal blocks. Observe stress cones and leakage sections for cleanliness and tracking. Replace as needed. Inspection Semi-Annual – Observe components visible through inspection windows: switch contacts. For other maintenance requirements. Check for loose bolts and insecure or inadequate supporting structure. clean as necessary. Space heaters Main switch blades and contacts 59 . lubricate. see section 10. excessive dirt film. Section 10 NOTE: Unless the maintenance interval is specified. wiring. conduct preventive maintenance annually (indicated by •) or as the equipment becomes available during an outage. and overheating of parts. See that blades are properly seated in the contacts.” in the body of this FIST volume. Check for chipped or broken porcelain. Check fuse latching and tripping mechanism for proper operation. space heater operation. Major Maintenance or Overhaul Structure and enclosure Base and mounting Ventilating louvers and air filters Buses. evidence of water leaks. operate the switch several times and see that blades are properly aligned to engage contacts. 19 – Maintenance Schedules and Records – October 1965. cable terminations. Record loads if equipped with meters. “Circuit Breakers. auxiliary devices. and bolts Insulators Maintenance to Perform Repair rust spots and paint. splices. Verify operation or operate continuously to overcome thermostat malfunction. cleanliness. adequate grounding. fuse clips and fuses. insulators and insulating materials. and tracking.Appendix C DISCONNECT SWITCH PREVENTIVE MAINTENANCE Adapted from Power O&M Bulletin No. Weekly – Note whether multiple-shot reclosing fuse has operated. clean contact surfaces if corroded. and cranks are in serviceable condition and repair as necessary. discard suspect switch operating hot sticks. check connections for correct tightness. if frayed. Evaluate and make necessary repairs. screws.” Potential. Adjust for adequate contact closure and over travel. Check motor operation and Megger®. and locknuts. Do not lubricate. “Personal Protective Equipment. Check for condition. test hot sticks per requirements under FIST Volume 4-1B. Check gears and bearings. Check clips for adequate spring pressure and proper fuse rating. See that stops are in place and tight. See that switch operating hot sticks are in good condition and are kept in a dry place. check contact springs. travel. Cable terminations and connections Meters Fuse clips and fuses Grounding Clean and inspect for surface tracking. Check and tighten bolts. Check base and operating handle ground connections. See that blade latches. lubricate. if not adequate. and cranks Gearboxes Operating motor and mechanism Auxiliary and limit switches Door and other interlocks Switch disconnect studs and finger Lubricate unless manufacturer’s instruction says clusters (if drawout type) not. Check condition of contacts and refinish with fine file if burned or corroded. and levers. alignment. check closing and opening positions with respect to main switch contacts. section 25. flush out oil or grease and relubricate. current. where provided.Continued Contact and hinge spring and shunts Blade latches and stops Check pressure springs in contact and hinge and replace. see that rods. check adjustment of brake. or motor mechanism. inspect hot sticks for damage and deterioration. are engaged. and proper operation. see that ground cable is not broken. Check calibration. levers. and control transformers Switch operating hot sticks 60 . lubricate pivot points and bearings. Functional test for proper sequence. levers. replace flexible shunts. Arcing switch blades and contacts Arc chutes or interrupter device Switch operating mechanism and linkage Operating rods. check latches for proper engaging and holding blade against opening force. operating rods. References FIST Volume 3-18. Replacing Glaze Burned Insulators 61 .