TECHNICAL TABLES AND FORMULAE Motor Currents Approximate current per phase for AC Motors at full load, assuming average efficiency and Power Factor. THREE PHASE AC MOTORS (415V AC) Power kW 0.75 1.1 1.5 2.2 3.0 4.0 5.5 7.5 11 15 18.5 22 30 37 45 55 75 90 110 132 150 160 185 200 220 250 315 355 400 450 500 Table 6.1 156 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 157 Horse Power HP 1.0 1.5 2.0 3.0 4.0 5.5 7.5 10 15 20 25 30 40 50 60 75 100 120 150 180 200 220 250 270 300 340 430 480 545 610 680 Full Load Current A 1.9 2.5 3.5 5.0 6.5 8.0 11 14 21 28 35 40 55 66 80 102 135 165 200 230 260 280 325 350 385 450 545 580 650 740 820 Three Phase Formulae kW = Line Amps x Line Volts x 1.732 x P.F 1000 = Line Amps x Line Volts x 1.732 1000 = kVA x P.F kVA kW Electric Motors Power Output kW Output kW Output = Power Input x Efficiency = kW Input x Efficiency = 1.732 x Line Volts x Line Amps x P.F x Efficiency 1000 = 1.732 x Line Volts x Line Amps 1000 = 1000 x kW Output Line Volts x 1.732 x P.F x Efficiency kVA Input Line Current (Input) Line Current (Input) = 1000 x kVA Input Line Volts x 1.732 PERMISSIBLE SHORT CIRCUIT TEMPERATURE AND THE PROSPECTIVE FAULT LEVEL FOR CABLES AND THEIR INSULATION Based on the final (permissible) short circuit temperature of a fault duration of 1 sec, the values for calculating the prospective fault are listed below. Insulation Permissible Rated Operating Temperature °C Silicone PVC EPR Untinned Conductor Tinned Conductor EVA Tinned Conductor Soldered Joint Table 6.2 Permissible Short Circuit Temperature °C 350 150 Conductor temperature at the beginning of the short circuit in °C 180 165 150 135 120 105 90 80 2 70 60 50 40 30 J thr for 1 sec in A/mm - 180 75 132 139 146 153 160 166 173 178 182 187 191 196 201 - 109 117 124 131 138 90 90 125 - 250 200 250 200 160 - - - - - - 143 148 154 159 165 170 176 122 128 135 141 147 153 159 49 - 65 - 79 36 91 58 126 135 143 148 154 159 165 170 176 102 112 122 128 136 141 147 153 159 74 87 100 107 115 122 129 136 143 158 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 159 J thr x conductor size in mm2 A 4 x 25mm2 EPR/CSP fully loaded and therefore having a continuous conductor operating temperature of 90oC I thr = 143 x 25 = 3.58 kA for 1 second For fault durations up to 5 sec or below 1 sec the following equation is applicable (example is for 0.2 sec fault). = I(1 1 sec = I(1s) x I thz 0.2 sec Formula for calculating the fault level I thr of a cable I thr Example: = Support for Vertically Suspended Cables The anchoring of cables is best achieved with a stress relief drum. The open ended construction facilitates installation and replacement while affording better stress relief and jacket protection than cable grips. At least 2 1/2 cable turns should be wound around the drum. Refer to the minimum Bending Radii data for each cable type to determine the stress relief drum diameter. Suggested stress relief drum design Connection Point Cable Suspension The maximum free suspension height in metres for reeling cables that must be vertically suspended shall be calculated utilising the following.This formula protects the copper conductors from deformation past their elastic limit. Conductor deformation leads to cork screws and possible core breakages. Height C CSA N W = = = = = C x CSA x N W x 9.8 Number of Conductors in the cable Conductor Cross Section in mm2 Max. Tensile limit in N/mm2 of the cable Cable Weight in kg/mtr = 59 mtrs maximum suspension height Fixed Mounting Single Clamp Stress Relief Drum Example: Cordaflex (K) 5 x 1.5 mm2 = 5 x 1.5 x 20 = 150 0.26 x 9.8 2.54 Cable 160 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 161 CHEMICAL RESISTANCE OF DIFFERENT Chemical PCP 3.3kV Flex PCP CSP CPE Mining MSR Planoflex Ozoflex Protolon (SM) Cordaflex (SMK) Protomont Rondoflex Neoprene 2 Hypalon P F G VG VG F VG G VG E E G E G G VG E E E E VG P VG E VG E E VG VG-E F F G VG VG VG VG G VG E VG G E G E E E E E E G P VG E VG E G VG VG CABLE SHEATH MATERIALS PU Spreaderflex EPR Hydrofirm EVA EVA125 SI Sinotherm PVCPU EPR Protoflex Pendantflex Neoprene 1 Acetic acid Benzene Bitumous tar Bleach (NaCLO2) Coke oven gas Diesel oil Ethylene glycol Gasoline Hydraulic oil Hydrochloric acid (21%) Hydrogen sulphide Kerosene Methanol Methyl ethyl keton Nitric acid (10%) Phosphoric acid (60%) Picric acid (10%) Potassium chloride Sodium hydroxide (25%) Sulphuric acid (50%) Transformer oil Trichlorethylene Vegetable oils & fats UV resistance Ozone resistance Water resistance Tear & notch resistance Low temp. flexibility Abrasion resistance P F G VG VG F VG G VG E E G E G G VG E E E E G P VG E VG E VG E VG Chlorinated Polyethylene F F G VG VG VG VG G VG E E G E G E E E E E E VG P VG E VG VG VG G G-VG G = Good Polyurethane F P G-VG F VG VG F E E F P VG F G F G F E P P E F-P E E E F E E E Ethylene Propylene P P P E VG F E F P P E F E E E E VG E E E F P VG E E E F-G E G Ethylvinyl Acetate F P P P G G F G VG F G G P P P P F E P P G P G VG E G F G VG Silicone VG P F VG F P E P E P P P E P P E P E P P P P E VG VG E P E P Polyvinyl Chloride P F G VG VG VG G F VG VG VG F G P VG E E E G VG VG P VG G E G VG G VG Table 6.3 E = Excellent VG = Very Good The results tabled are generic for each particular sheath compound and attack, temperature and contact contamination F = Fair P = Poor should be used as such. For a more exact evaluation, the chemical concentration, duration of should be known. Polyethylene EPR Ethylene Propylene Rubber EVA Ethyl vinyl Acetate PVC Polyvinyl Chloride PCP Polychloroprene (Neoprene) CSP Chlorosulphonated Polyethylene (Hypalon) CPE Chlorinated 162 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 163 Formula 1 Actual Volts Vd = where Vd = L= I= mV/Am = VOLT DROP L x I x mV/Am 1000 volt drop in volts route length of cable in metres current to be carried in Amps millivolt per ampere metre value from Tables 6.4 and 6.5. In accordance with AS 3000 the permissible volt drop from the point of the connection is 5% of the supply voltage. The following tables and formula should be used to satisfy volt drop limitations. Three Phase Voltage Drop - Single Core Cables in Trefoil Conductor Size 45°C mm2 1.0 1.5 2.5 4 Max. 33.9 22.9 13.7 8.68 5.80 3.43 2.18 1.28 1.00 0.748 0.532 0.411 0.331 0.286 0.244 0.213 0.192 0.178 0.168 0.159 0.244 0.210 0.186 0.167 0.153 0.141 0.8pf Max. 35.9 24.1 14.4 9.14 6.11 3.64 2.30 1.35 1.06 0.788 0.558 0.430 0.345 0.303 0.251 0.218 0.197 0.182 0.170 0.160 0.251 0.215 0.191 0.171 0.156 0.142 Three Phase Voltage Drop at 50Hz, mV/Am Conductor Temperature °C 60°C 0.8pf 75°C Max. 37.6 25.3 15.2 9.62 6.42 3.83 2.41 1.42 1.11 0.824 0.584 0.447 0.357 0.307 0.260 0.223 0.201 0.184 0.171 0.161 0.259 0.221 0.196 0.174 0.159 0.144 0.8pf 90°C Max. 0.8pf 39.5 26.7 15.9 10.1 6.74 4.00 2.53 1.48 1.16 0.863 0.627 0.464 0.371 0.319 0.269 0.267 0.229 0.227 0.206 0.201 0.187 0.178 0.173 0.161 0.164 0.150 *With this method the drop in voltage (in volts) is given and shall not exceed 5% of the supply voltage, i.e., 5% of 415V = 20.75V. Formula 2 mV/A.m value Vc where = Vc = Vd = L= I= 1000 x Vd LxI millivolts per Ampere metre volt drop in volts route length of cable in metres current to be carried in Amps 6 10 16 25 35 50 70 95 120 150 185 240 300 400 500 630 Table 6.4 * With this method the millivolts per ampere metre is given and the appropriate conductor size shall be selected from Tables 6.5 and 6.6. The conductor size selected shall be nearest to, but not exceed the formula result, e.g., 415V, 3 phase installation, load demand is 55A, 100m length: OZOFLEX Result: 3.77mV/A.m 4 x 10mm2 164 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 165 WIRING SYSTEMS IN HAZARDOUS AREAS (Not applicable to coal mining areas) Three Phase Voltage Drop - Multicore Cables Conductor Size 45°C mm2 1.0 1.5 2.5 4 6 10 16 25 35 50 70 95 120 150 185 240 300 400 500 630 Table 6.5 Three Phase Voltage Drop at 50Hz, mV/Am Conductor Temperature °C 60°C Max 0.8pf 36.5 24.4 14.7 9.32 6.24 3.69 2.32 1.37 1.07 0.797 0.559 0.424 0.339 0.284 0.242 0.201 0.180 0.164 0.147 0.139 75°C Max. 0.8pf 38.6 25.6 15.5 9.82 6.56 3.90 2.46 1.44 1.12 0.837 0.589 0.445 0.353 0.298 0.253 0.208 0.184 0.173 0.149 0.140 90°C Max. 0.8pf 40.4 29.0 16.2 10.3 6.88 4.07 2.58 1.51 1.18 0.875 0.613 0.464 0.367 0.308 0.260 0.213 0.197 0.189 0.151 0.142 Intrisically safe systems in accordance with AS 2381.7 Cable in metallic conduit Served MIMS PVC, elastomer or silicone sheathed; circular unarmoured PVC, elastomer or silicone sheathed; armoured Cables in rigid and flexible, non-metallic conduit Metal sheathed, served and armoured Flexible cords and cables in accordance with Clause 3.16.1 AS 2381.1 - 1991 0.213 0.188 0.165 0.145 0.131 Cables in corrugated non-metallic conduit Metal sheathed, served and unarmoured X denotes acceptable use Class I Zone 0 Zone 1 Zone 2 X X X X X X X X X X X X X X X X X X X X Class II Max. 33.4 23.2 14.0 8.85 5.91 3.52 2.22 1.30 1.01 0.759 0.533 0.438 0.324 0.274 0.234 0.196 0.175 0.161 0.145 0.138 0.8pf X X X X X X X X 0.196 0.175 0.154 0.136 0.124 0.201 0.178 0.158 0.139 0.126 0.207 0.183 0.162 0.142 0.128 X X Table 6.6 NOTE: The values in the tables are taken from AS 3008.1 and based on cables operating at maximum conductor temperature. For lightly loaded cables the standard also permits determination of the appropriate Vd in such cases and therefore the tables list reduced conductor temperatures. Clause 3.16.1 - AS2381.1-1991 states that the maximum length of the flexible cable shall be 600mm in Class 1 Zone 0 and Zone 1. This table, extracted from the hazardous location standard AS2381.1, nominates the allowable cable types for each Class and Zone classification. Fibre optic cables can be used in all areas without further protection. Sales Phone 131 773 Technical Support Phone 03) 9721 7281 167 166 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 DE-RATING FOR PARALLEL CONNECTION The following factors should be applied to conductors connected in parallel for the various methods of installation. Table taken from AS 3008.1. Arrangement of Cables 1 1. 2. Bunched in air Bunched on a surface or enclosed in conduit or ducting Single layer on wall or floor Single layer under ceiling Touching Spaced* Touching Spaced* 1.00 1.00 1.00 1.00 0.95 0.95 2 0.87 0.80 0.85 0.94 0.81 0.85 3 0.75 0.70 0.79 0.90 0.72 0.85 4 0.72 0.65 0.75 0.90 0.68 0.85 5 0.70 0.60 0.73 0.90 0.64 0.85 6 0.67 0.57 0.72 0.90 0.63 0.85 7 0.54 0.72 0.90 0.62 0.85 De-rating Factors No. of Circuits/Cables in parallel 8 9 10 12 14 0.52 0.71 0.90 0.61 0.85 0.50 0.70 0.90 0.85 0.48 0.90 0.85 0.45 0.90 0.85 0.43 0.90 0.85 16 0.41 0.90 0.85 18 - 20 or more - 0.39 0.38 - 3. 4. 5. 6. 0.90 0.90 - 0.85 0.85 Table 6.7 NOTE: De-rating is necessary for the purpose of thermal dissipation. If sufficient clearance from adjacent conductors/cables is allowed for then no de-rating is necessary. To avoid de-rating a minimum clearance of 2 x cable O.D for horizontal, and 4 x cable O.D for vertical installation in air are given in AS 3008.1 * Spaced in the above table indicates a clearance of 1 x cable O.D between adjacent cables. 168 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 169 ATTENUATION DATA FOR CORDAFLEX AND Attenuation Data for Individually Individually Screened Conductors Screened Frequency Line Attenuation Impedance Conductors Hz dB/1000ft dB/km Z 300 0.26 0.85 200 600 0.37 1.2 150 1200 0.52 1.7 110 2400 0.70 2.3 90 4800 0.98 3.2 60 9600 1.28 4.2 50 19200 1.52 5.0 40 38400 1.83 6.0 38 48000 1.92 6.3 35 57600 1.38 6.5 35 115200 2.44 8.0 35 153600 2.59 8.5 35 Table 6.8 PLANOFLEX SCREENED CORES Capacitance pF/ft nF/km 61.0 200.2 61.0 200.0 61.0 200.0 60.9 199.9 60.8 199.6 60.7 199.0 60.5 198.6 60.4 198.0 60.3 197.9 60.3 197.8 60.2 197.4 60.1 197.2 Inductance mH/1000ft mH/km 0.08 0.256 0.08 0.256 0.08 0.256 0.08 0.256 0.08 0.256 0.08 0.256 0.08 0.256 0.08 0.251 0.08 0.249 0.08 0.248 0.07 0.238 0.07 0.235 Resistance Ω/1000ft Ω/km 15.2 50 15.2 50 15.2 50 15.2 50 15.2 50 15.2 50 15.2 50 15.8 52 16.5 54 16.8 55 19.2 63 20.4 67 Attenuation Data for Twisted Twisted Screened Pairs Screened Pair Frequency Line Attenuation Impedance Conductors Hz dB/1000ft dB/km Z 300 0.13 0.42 250 600 0.18 0.60 200 1200 0.24 0.80 150 2400 0.30 1.0 130 4800 0.40 1.3 100 9600 0.46 1.5 90 19200 0.61 2.0 85 38400 0.85 2.8 80 48000 1.01 3.3 78 57600 1.07 3.5 75 115200 1.68 5.5 70 153600 1.74 5.7 70 Table 6.9 Capacitance pF/ft nF/km 31.3 102.6 30.9 101.4 30.5 100.2 30.2 99.2 30.1 98.6 29.9 98.1 29.8 97.6 29.6 97.2 29.6 97.0 29.5 96.9 29.4 96.4 29.3 95.9 Sales Phone 131 773 Inductance mH/1000ft mH/km 0.21 0.69 0.21 0.69 0.21 0.69 0.20 0.67 0.20 0.66 0.20 0.65 0.19 0.61 0.17 0.56 0.16 0.54 0.16 0.52 0.14 0.47 0.14 0.46 Resistance Ω/1000ft Ω/km 7.9 26 7.9 26 7.9 26 7.9 26 7.9 26 9.1 30 11.0 36 14.6 48 15.8 52 17.1 56 23.8 78 26.8 88 171 170 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 DC AND AC RESISTANCE OF FLEXIBLE CABLES Conductor Size Single Core Conductor Temperature °C DC resistance Ω/km 20°C 38.2 25.4 19.1 13.0 7.82 4.85 3.32 1.93 1.18 0.710 0.521 0.391 0.258 0.202 0.156 0.123 0.101 0.0835 0.0613 0.0452 0.0373 AC resistance at 50 Hz, Ω/km 60°C 29.4 22.1 15.0 9.05 5.61 3.74 2.23 1.37 0.822 0.603 0.453 0.299 0.235 0.182 0.144 0.119 0.0928 0.0740 0.0565 0.0483 75°C 30.9 23.2 15.8 9.51 5.90 3.93 2.35 1.44 0.864 0.634 0.476 0.314 0.246 0.191 0.151 0.125 0.0972 0.0775 0.0590 0.0503 90°C 32.4 24.4 16.6 10.0 6.18 4.12 2.46 1.50 0.906 0.665 0.499 0.330 0.258 0.200 0.158 0.131 0.102 0.081 0.0615 0.0523 AND CORDS WITH COPPER CONDUCTORS Conductor Size Multicore Conductor Temperature °C DC resistance Ω/km 20°C 40.1 26.7 20.0 13.7 8.21 5.09 3.39 2.02 1.24 0.746 0.547 0.410 0.271 0.212 0.164 0.129 0.106 0.0877 0.0644 0.0475 0.0392 AC resistance at 50 Hz, Ω/km 60°C 45.1 30.9 23.1 15.9 9.50 5.89 3.92 2.34 1.44 0.864 0.633 0.475 0.315 0.247 0.191 0.151 0.125 0.0981 0.0787 0.0606 0.0522 75°C 47.4 32.5 24.3 16.7 10.0 6.19 4.12 2.46 1.51 0.908 0.666 0.499 0.331 0.259 0.201 0.159 0.131 0.103 0.0824 0.0632 0.0542 90°C 49.7 34.0 25.5 17.5 10.5 6.49 4.32 2.58 1.58 0.952 0.698 0.523 0.346 0.271 0.211 0.166 0.138 0.107 0.0860 0.0658 0.0563 mm2 0.5 0.75 1.0 1.5 2.5 4 6 10 16 25 35 50 70 95 120 150 185 240 300 400 500 Table 6.10 mm2 0.5 0.75 1.0 1.5 2.5 4 6 10 16 25 35 50 70 95 120 150 185 240 300 400 500 Table 6.10 lists measured values that conform to AS 3008.1 for rope laid flexible cables. For cables with an alternate core length of lay (e.g., CORDAFLEX) the values will alter slightly. 172 Technical Support Phone 03) 9721 7281 Sales Phone 131 773 Sales Phone 131 773 Technical Support Phone 03) 9721 7281 173