ISA 5.4 Instrument Loop Diagrams

AMERICAN NATIONAL STANDARDANSI/ISA–S5.4–1991 Instrument Loop Diagrams Approved 9 September 1991 Copyright The Instrumentation, Systems, and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale, 02/12/2006 06:09:12 MST --``,`,`,,,,`,,,,`,```,``````,`-`-`,,`,,`,`,,`--- ISA-S5.4 — Instrument Loop Diagrams ISBN 1-55617-227-3 Copyright © 1986 by the Instrument Society of America. All rights reserved. Printed in the United States of America. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), without the prior written permission of the publisher. ISA 67 Alexander Drive P.O. Box 12277 Research Triangle Park, North Carolina 27709 Copyright The Instrumentation, Systems, and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale, 02/12/2006 06:09:12 MST --``,`,`,,,,`,,,,`,```,``````,`-`-`,,`,,`,`,,`--- . Research Triangle Park. this Department will try to introduce SI-acceptable metric units in all new and revised standards to the greatest extent possible.`. 02/12/2006 06:09:12 MST 3 . O.A.. symbols. published by the Institute of Electrical and Electronics Engineers as ANSI/IEEE Std. P. 67 Alexander Drive. Systems. At the time it approved this standard revision. users of ISA standards of incorporating suitable references to the SI (and the metric system) in their business and professional dealings with other countries. or of any of the standards that ISA develops.`-`-`. Richard Shaw Gerald V. The Metric Practice Guide. Toward this end.. Larkin J. e-mail: standards@isa. and request that they be addressed to the Secretary. this document should not be static. abbreviations. the ISA-S5. Emerson Edward E.`.```.4 Committee had the following members: NAME W..``````. Olinek Raymond Robertson Robert P. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``. ISA.Preface The information contained in the Preface and Forward is for information only and is not a part of the standard.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. the Society welcomes all comments and criticisms..`. Telephone (919) 549-8411.. Terhune Mike Wiley Thomas C. McAvinew COMPANY Stearns Roger* Dow Corning Corporation Stone & Webster Bechtel Power Corporation Stearns Roger* PPG Ford.`.S. To be of real value. The Department is further aware of the benefits to U. Barta William H.. Bacon & Davis Delmar Controls Leeds & Northrup Consultant Lummus Crest Metropolitan Denver Sewage Disposal District Copyright The Instrumentation. in the preparation of instrumentation standards.`.org. This standard is prepared as part of the service of ISA toward a goal of uniformity in the field of instrumentation.`... Participation in the ISA standards-making process by an individual in no way constitutes endorsement by the employers of the individual. 268-1982.`. Cleary Richard L. Slavin John Lorenz Richard E. but must be subject to periodic review. and conversion factors. and future revisions will be the reference guide for definitions. of the ISA.`--- *One vote ANSI/ISA-S5. Box 12277. The ISA Standards and Practices Department is aware of the growing need for attention to the metric system of units in general and the International System of Units (SI) in particular. It is the policy of ISA to encourage and welcome the participation of all concerned individuals and interests in the development of ISA standards. NC 27709. Toward this end. Standards and Practices Board. . Consultant Moore Products Company Bechtel Western Power Corporation Consultant Stearns Catalytic Corporation Copyright The Instrumentation. of Standards & Technology The Power Supply System Consultant The Foxboro Company Consultant Consultant Consultant Florida State University Philadelphia Electric Company Consultant Consultant Honeywell. Magison* R.`.```.`. Combs* R. Eagle Technology Utility Products of Arizona Dow Chemical Company Chagrin Valley Controls. Vice-President N.`--- *Director Emeritus 4 ANSI/ISA-S5.`-`-`..`. Jones* R. Inc. Prescott D. Williams* COMPANY Chevron U.This recommended practice was approved for publication by the ISA Standards and Practices Board in 1989.``````. Bishop.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. Rennie W..S.. Inc. Inc. 02/12/2006 06:09:12 MST ..`.. Inc. Widmeyer P.A. Gross H.`. Marvin* W. Calder III* B. Lovett* E. Nesvig R.`. Hopkins R. Keller* O. Weidman J. Galley* T. Fisher Controls Int'l. National Inst. Moore Products Company Rapley Engineering Service Allen-Bradley Company Factory Mutual Research Corporation Gilbert/Commonwealth.. Inc. Platt* J. Bliss* W. McCauley E.. Harrison* R. Systems. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``. Conger C. NAME D. Miller* J. Mock* G. Christensen* L. Jones A. Whetstone M. Reimer J..`. Rapley R. ERDCO Engineering Corp. Foreword Instrument loop diagrams are suitable for general use throughout industry. operation. It can present on one sheet all the information or references to the information needed for installation... This committee is appreciative of the work of previous SP5.. it has the same strengths and weaknesses as other consensus standards.`.`-`-`.`. One of our major goals has been to have the S5. Without the use of an instrument loop diagram. improved loop integrity and purchasing accuracy. start-up and maintenance. and easier maintenance troubleshooting.`. Its primary strength is that the format and content guidelines apply to the majority of instrumentation applications.```.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. Updating this single diagram to "as built" status is more easily achieved than updating the variety of other documents.1 standard. start-up.`. 02/12/2006 06:09:12 MST 5 --``. As such. but rather it is a consensus concerning their generation. rearrangement. An instrument loop diagram can be effective on any size project from one or two loops up to large and complex installations.1 committee in developing ISA-S5. construction. Instrumentation Symbols and Identification. Its weakness is that it is not specific enough to satisfy the special requirements of particular interest groups. This committee would like to acknowledge the work of the SP5. The ISA Standards Committee on Instrument Loop Diagrams operates within the ISA Standards and Practices Department. This standard does not mandate the style and content of instrument loop diagrams. maintenance. Systems..`.4 committees and has tried to treat their work with respect.4 standard conform to the revised S5. and reconstruction.``````... and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS ANSI/ISA-S5.1.. Benefits can include reduction in engineering costs.`. Copyright The Instrumentation.`. It is important to consider their value for design.. checkout.`--- . that information is spread among many other documents and is not readily available. checkout.. ....`-`-`. 02/12/2006 06:09:12 MST ..`.`.`.`.`--- Copyright The Instrumentation.`.--``..```.`..``````. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale..`. Systems.. ...................... 9 2 Scope ................ 10 5 Content ................................................................. 9 3...................... 9 3......................`.....................................................................................Contents 1Purpose ................`...`--- ANSI/ISA-S5...................................................... 10 3........ 02/12/2006 06:09:12 MST 7 ............4 Start-up ...................................`........1 Instrument connection and action information .............................................................................. 9 3......................................................................... Systems...........................3 Instrument terminals or ports ............. 10 3.............................................................2 Design .. 13 7.......................................1 Serve many purposes.......... 12 7..............4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale................................`-`-`.................................7 Modification ..................................................5 Operation .................................................................................................................. 13 7..........................................3 Construction ..............................4 Instrument system energy supply .`..`............................................................................................................``````.... 14 Copyright The Instrumentation...................................................... 10 3........... 9 3......................................................................................................................................................................................................................... 14 8 Examples ...............................................................................................5 Identification of instrument action ....................................................................6 Maintenance .............................................. 10 4 Definitions ......................................................................................................................................................................................................................... 12 7..............................................................................................`..................`.................... 10 6 Format ........................................... 9 3 Applications .................................. 12 7 Symbols .....2 General terminal or bulkhead symbol ........................................... and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``................... 13 7....................................```............. .```.. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale.`..`-`-`.`.`..`...`.`--- . 02/12/2006 06:09:12 MST --``.`. Systems..``````..Copyright The Instrumentation.`.. Copyright The Instrumentation. Several of these stated below are in the chronology of project development. air conditioning. navigation.`--- 2 Scope 2. and modification of instrumentation systems.3 Specialty fields.`. such as astronomy. 1. operation.`.. This loop is typically part of a process depicted on the class of engineering drawings referred to as Piping and Instrument Drawings (P&IDs). and many other industries. start-up.. 02/12/2006 06:09:12 MST 9 . this standard is flexible enough to meet many of the needs of specialty fields.`. operating.``````. connections between devices. design.. management. metal refining. and maintenance personnel. non-technical.3 Construction 1) Panel instrumentation interconnections and checkout diagram ANSI/ISA-S5. 2.`-`-`.. Systems. 3. construction. which show the components and accessories of the instrument loop.1 Serve many purposes.2 Design 1) 2) 3) Illustrate control philosophy and confirm the completeness of submitted data An extension of P&IDS.`.. No specific effort to have this standard meet the requirements of those fields has been made. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``. Loop diagrams serve many purposes.`. This standard is suitable for use in the chemical. maintenance.2 Assist understanding..2 Suitability.1 Provide guidelines. and identification of component action The specification of instrument hardware items and a means of communicating requirements to vendors 3. construction.`. This standard will provide guidelines for the preparation and use of instrument loop diagrams in the design.`.```..1 Additional information for individual loop. This standard will assist the understanding of instrument loop diagrams and improve communications among technical.1 Purpose 1. use very specialized instruments that are different from the conventional industrial process instruments.. and medicine. This standard establishes minimum required information and identifies additional optional information for a loop diagram for an individual instrumentation loop. petroleum. 2. However. 3 Applications 3. Certain fields. power generation..4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. `.`--- 3.`.7 Modification 1) 2) 3) Rearrangement Reconstruction Enhancement 4 Definitions This standard is an extension of the communications defined by ISA-S5. maintenance.6 Maintenance 1) 2) 3) Troubleshooting Routine calibration Preventative and corrective maintenance tool 3.`. and it does not produce any new definitions for that presentation process.`..`-`-`. Systems. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS 10 ANSI/ISA-S5. The instrument loop diagram is a composite representation of instrument loop information.5 Operation 1) 2) Communication medium between operations.`...2) 3) 4) 5) Instrumentation installation references and special requirements Instrumentation interconnections Instrumentation loop checkout Inspection and documentation 3.. The guidelines of this standard cover the content of a loop diagram drawing. “Instrumentation Symbols and Identification”.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale.4 Start-up 1) 2) Pre-start-up commissioning and calibration Training tool and aid --``.1 General.`...1. Classified below are minimum requirements and some established options that can be used to match the desired uses. It contains all associated electrical and piping connections and should contain all of the information needed to accommodate the intended uses.`.. and the definitions of that standard therefore apply.``````.```. 02/12/2006 06:09:12 MST . and engineering personnel Training device for operations 3. 5 Content 5.. Copyright The Instrumentation.. “Instrumentation Symbols and Identification”. etc. designation. purchase order numbers. including overrides. Process lines and equipment sufficient to describe the process side of the loop and provide clarity of control action. Specific location of each device. Energy sources of devices. and instrument specifications. terminals. 02/12/2006 06:09:12 MST Copyright The Instrumentation. area. Identify voltage... termination cabinet.`. or flow direction.1. and their identification numbers. or both) of control devices such as controllers.3 Optional content information. I/O location. All point-to-point interconnections with identifying numbers or colors of electrical cables. wiring diagrams or drawings.`-`-`. etc. cable spreading room. and grounding connections..`. bulkheads. “Instrumentation Symbols and Identification”. and transmitters (if reverseacting).. source. For electrical sources. an instrument loop diagram shall contain the information covered below. model numbers. Systems. 11 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. P&IDs. Stated below are typical examples of items for inclusion at the user's discretion.2 Minimum content requirements. location drawings.1. air supply. Other principal components of the loop to be shown and identified under ISA-S5. Software reference numbers. and other applicable requirements. including setpoint values for switches. solenoid valves. such as electrical power. and hydraulic fluid supply. Indication of the interrelation to other instrumentation loops. switches. auxiliary equipment. conductors. Cross reference between loops that share a common discrete component. panel. network interfaces.`. and alarm and shutdown devices. such as installation details. and individual pneumatic and hydraulic tubing. etc. If not adequate..`. Actions or fail-safe positions (electronic. interlocks.`--- 5) 6) 7) 8) 5. such as multipen recorders. As a minimum. manufacturers. lines. Signal ranges and calibration information. use a supplemental note.4-1991 . 1) Identification of the loop and loop components shown on the P&IDS. These are to be identified in accordance with ISA-S5.5. pressure. Engraving or legend information that helps identify the instrument or accessory. rack.`. etc.``````.`. hardware types.. shutdowns and safety circuits. I/0 cabinet. Identify any special features or functions of shutdown and safety circuits. identify circuit or disconnect numbers. Include what is being measured and what is being controlled. cascaded set points. pneumatic multitubes. References to equipment descriptions.. such as elevation. control valves.. Word description of loop functions within the title. 2) 3) 4) --``. Reference to supplementary records and drawings.```. ports. 1) 2) 3) 4) 5) 6) 7) 8) Process equipment. This identification of interconnections includes junction boxes. such as I/O addresses. panel subdivision. control block types and names. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS ANSI/ISA-S5. dual indicators. Additional information needs to be considered for its effectiveness in accommodating the intended uses. General location of devices such as field.. pneumatic.`. rack or cabinet number and location. point names. etc. specifications or data sheets. .`. Prevent overcrowding and provide space for future additions and loop data.`.`. Attention to the proper size of text and symbols will keep them legible on reduced copies.`-`-`. The minimum size for the original drawing should be 11 inches X 17 inches.`--- 7. tagged or otherwise identified. 02/12/2006 06:09:12 MST --``. 11) Color code identification for conductors or tubes that use numbers for differentiation. purge meters.`. and instrument action is necessary to provide the information required on instrument loop diagrams. An instrument loop diagram should typically contain only one loop. such as regulators. etc. 7 Symbols NOTE: The terminals or ports shown are not to be pictorial. Use judgment to accommodate the individual situations where loops that share common components can be adequately and completely communicated on a single diagram.`.```. 10) References to manufacturer's documentation such as schematics.. filters. root valves.1 Instrument connection and action information... (For convenience in printing and binding.1 apply for instrument loop diagrams..4 General layout. Copyright The Instrumentation..3 Drawing content. 6.. manifold valves. Avoid showing a loop on multiple pages or sheets where practical. operating instructions. A suggested layout is to divide the drawing into sections for relative locations of devices. connection details.9) Accessories. expansion of those symbols to include connection points. Maintain a consistent layout (horizontal or vertical) throughout a project.1 Consistency for ease of use. hydraulic). etc. energy source (electrical.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale.``````.. this standard uses reduced size example figures.`.`. The symbols in ISA-S5.2 Size of drawing. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS 12 ANSI/ISA-S5. 6 Format 6. Systems. . The following format conventions should be consistently employed for improved communications and ease of use. 6.) 6. However.. air. `.``````... 02/12/2006 06:09:12 MST 13 .`.```.3 Instrument terminals or ports 7.`-`-`.4.`--- Copyright The Instrumentation.7.1 Electrical power supply.`.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. Identify electrical power supply followed by the appropriate supply level identification and circuit number or disconnect identification...`..`... 7. Identify air supply followed by air supply pressure.`. Systems.2 General terminal or bulkhead symbol 7.4.2 Air supply.. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS ANSI/ISA-S5. --``..4 Instrument system energy supply 7.`. .`.1 Typical symbols for various control hardware. 14 ANSI/ISA-S5. 8..`-`-`. and 3 show the minimum required items on those loop diagrams.7. The example figures illustrate this standard's symbols and identifications that are typical for the various instrument hardware types.`--- 8 Examples 8. as the value. 8.3 Hydraulic fluid supply. plus examples of optional items presented in various alternate formats.`.`. of the input (measured variable) increases by the letters "REV..`. Copyright The Instrumentation.5 Identification of instrument action... This usage does not imply. Figures 4 through 6 show the minimum required items.2 Examples of minimum required items. Sample instrument loop diagrams illustrate the use of the symbols for various relatively simple feedback flow control loops. Show the direction of the instrument signal by placing appropriate letters close to the instrument bubble. however.`.. Systems. the designation DIR is optional for them..3 Examples of minimum plus optional items.`.``````." Identify an instrument in which the value of the output signal decreases or changes to its minimum value.4..`.```.. since most transmitters are direct-acting. as input (measured variable) increases by the letters "DIR. 02/12/2006 06:09:12 MST . No inference is to be drawn from the choice of any of the information depicted as being a recommendation for the illustrated control method. that the applications or designations of the symbols or identifications are restricted in any way. Identify an instrument in which the value of the output signal increases or changes to its maximum value. Figures 1." However.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. 2. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``. 7. Identify hydraulic fluid followed by the fluid supply pressure. `.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. pneumatic control.`...```.. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``.`...`-`-`.. ANSI/ISA-S5.`.`--- Figure 1 — Loop diagram.`.``````. Systems.Copyright The Instrumentation. 02/12/2006 06:09:12 MST 15 ..`.`. minimum required items... ```.`. minimum required items. Systems.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale.`.`-`-`..``````.Copyright The Instrumentation.`.`.... and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS --``.. electronic control....`--- Figure 2 — Loop diagram.`..`. 02/12/2006 06:09:12 MST .`. 16 ANSI/ISA-S5. `... minimum required items.`.`-`-`.`.``````.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale..Figure 3 — Loop diagram.`. Copyright The Instrumentation.`. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS ANSI/ISA-S5. 02/12/2006 06:09:12 MST 17 --``...`..`--- . shared display and control..```. Systems.`... ``````. 02/12/2006 06:09:12 MST --``. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS 18 ANSI/ISA-S5.`.`.`.Figure 4 — Loop diagram.`.. Copyright The Instrumentation. pneumatic control.`. Systems..`....`..4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale. minimum required items plus optional items.`-`-`...```..`--- . `.```.`.``````..`--- .. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS ANSI/ISA-S5.. 02/12/2006 06:09:12 MST 19 --``.Figure 5 — Loop diagram.`. Copyright The Instrumentation. Systems.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale.`-`-`...`...`.. minimum required items plus optional items. electronic control.`.`.. .. 02/12/2006 06:09:12 MST .Figure 6 — Loop diagram.`.4-1991 Licensee=Technip Abu Dabhi/5931917101 Not for Resale.`--- Copyright The Instrumentation. --``.``````.`. minimum required items plus optional items. Systems..`..`.`. shared display and control.. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS 20 ANSI/ISA-S5....`.```.`-`-`.`.. ```..`...`.`.. 02/12/2006 06:09:12 MST --``..`-`-`.`--- .`.``````...Copyright The Instrumentation.`.. Systems.`. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale..`. `-`-`. Systems. ISA administers United States Technical Advisory Groups (USTAGs) and provides secretariat support for International Electrotechnical Commission (IEC) and International Organization for Standardization (ISO) committees that develop process measurement and control standards.. please write: ISA Attn: Standards Department 67 Alexander Drive P.`... ISA is an American National Standards Institute (ANSI) accredited organization.```... NC 27709 ISBN: 1-55617-227-3 --``.. To obtain additional information on the Society's standards program. recommended practices..`.`.`. and reviewers. Box 12277 Research Triangle Park. and Automation Society Provided by IHS under license with ISA No reproduction or networking permitted without license from IHS Licensee=Technip Abu Dabhi/5931917101 Not for Resale.. To achieve this goal the Standards and Practices Department relies on the technical expertise and efforts of volunteer committee members.``````. 02/12/2006 06:09:12 MST .`.`.O. chairmen.. and technical reports is one of ISA's primary goals.Developing and promulgating technically sound consensus standards.`.`--- Copyright The Instrumentation.