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Chapter 4

NEC & NEMA Standards

1

This section lists excerpts from industry, national, and international standards. The excerpts are for illustration and educational purposes. There are often several related tables and information for other configurations and applications. In addition, the standards have added detail and information that applies to all these excerpts. Therefore, any application should refer to the standard, rather than the excerpts.

Standard National Electrical Code (NEC) NFPA 70-2005 National Electrical Safety Code (NESC) IEEE C2-2002 Motors and Generators (MG1) NEMA MG1-2003 Organization National Fire Protection Association, Batterymarch Park, Quincy, MA Institute of Electrical & Electronics Engineers, New York, NewYork National Electrical Manufacturers Association Application Electrical installations in occupancies Electrical supply stations, overhead, and underground lines. Performance of motors and generators

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NEC 240.6(A)

15 125 600 20 150 700

Electric Power Systems

Standard Ampere Ratings for Fuses & Circuit Breakers

25 175 800 30 200 1000 35 225 1200 40 250 1600 Amperes 45 50 300 350 2000 2500 60 400 3000 70 450 4000 80 500 5000 90 6000 100 -

Durham

110 -

Chapter 4

NEC & NEMA Standards

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Table 310.16 Allowable Ampacities of Insulated Conductors Rated 0 Through 2000 Volts, 60°C Through 90°C (140°F Through 194°F), Not More Than Three Current-Carrying Conductors in Raceway, Cable, or Earth (Directly Buried), Based on Ambient Temperature of 30°C (86°F)

Temperature Rating of Conductor (See Table 310.13.) 60°C 75°C 90°C 60°C 75°C 90°C (140°F) (167°F) (194°F) (140°F) (167°F) (194°F) Size AWG Types Types RHW, Types TBS, SA, SIS, Types Types RHW, Types TBS, SA, Size or kcmil TW, UF THHW, THW, FEP, FEPB, MI, RHH, TW, UF THHW, SIS, THHN, THHW, AWG or THWN, RHW-2, THHN, THHW, THW, THW-2, THWN-2, kcmil XHHW, USE, THW-2, THWN-2, THWN, RHH, RHW-2, USEZW USE-2, XHH, XHHW, XHHW, USE 2, XHH, XHHW, XHHW-2, ZW-2 XHHW-2, ZW-2 COPPER ALUMINUM OR COPPER-CLAD ALUM 18 -- -- 14 -- -- -- -- 16 -- -- 18 -- -- -- -- 14* 20 20 25 -- -- -- -- 12* 25 25 30 20 20 25 12* 10* 30 35 40 25 30 35 10* 8 40 50 55 30 40 45 8 6 55 65 75 40 50 60 6 4 70 85 95 55 65 75 4 3 85 100 110 65 75 85 3 2 95 115 130 75 90 100 2 1 110 130 150 85 100 115 1 1/0 125 150 170 100 120 135 1/0 2/0 145 175 195 115 135 150 2/0 3/0 165 200 225 130 155 175 3/0 4/0 195 230 260 150 180 205 4/0 250 215 255 290 170 205 230 250 300 240 285 320 190 230 255 300 350 260 310 350 210 250 280 350 400 280 335 380 225 270 305 400 500 320 380 430 260 310 350 500 600 355 420 475 285 340 385 600 700 385 460 520 310 375 420 700 750 400 475 535 320 385 435 750 800 410 490 555 330 395 450 800 900 435 520 585 355 425 480 900 1000 455 545 615 375 445 500 1000 1250 495 590 665 405 485 545 1250 1500 520 625 705 435 520 585 1500 1750 545 650 735 455 545 615 1750 2000 560 665 750 470 560 630 2000 CORRECTION FACTORS Ambient For ambient temperatures other than 30°C (86°F), multiply the allowable ampacities Ambient Temp. shown above by the appropriate factor shown below. Temp. (°C) (°F) 21­25 1.08 1.05 1.04 1.08 1.05 1.04 70­77 26­30 1.00 1.00 1.00 1.00 1.00 1.00 78­86 31­35 0.91 0.94 0.96 0.91 0.94 0.96 87­95 36­40 0.82 0.88 0.91 0.82 0.88 0.91 96­104 41­45 0.71 0.82 0.87 0.71 0.82 0.87 105­113 46­50 0.58 0.75 0.82 0.58 0.75 0.82 114­122 51­55 0.41 0.67 0.76 0.41 0.67 0.76 123­131 56­60 -- 0.58 0.71 -- 0.58 0.71 132­140 61­70 -- 0.33 0.58 -- 0.33 0.58 141­158 71­80 -- -- 0.41 -- -- 0.41 159­176 * See 240.4(D).

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Table 310.15(B)(2)(a) Adjustment Factors for More Than Three CurrentCarrying Conductors in a Raceway or Cable

Number of CurrentCarrying Conductors 4­6 7­9 10­20 21­30 31­40 41 and above

Electric Power Systems

Durham

Percent of Values in Tables 310.16 through 310.19 as Adjusted for Ambient Temperature if Necessary 80 70 50 45 40 35

Table 310.15(B)(6) Conductor Types and Sizes for 120/240-Volt, 3-Wire, Single-Phase Dwelling Services and Feeders. Conductor Types RHH, RHW, RHW-2, THHN, THHW, THW, THW-2, THWN, THWN-2, XHHW, XHHW-2, SE, USE, USE-2

Conductor (AWG or kcmil) Copper Aluminum or Copper-Clad Aluminum 4 2 3 1 2 1/0 1 2/0 1/0 3/0 2/0 4/0 3/0 250 4/0 300 250 350 350 500 400 600 Service or Feeder Rating (Amperes) 100 110 125 150 175 200 225 250 300 350 400

Chapter 4

NEC & NEMA Standards

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Figure 430.1

Article 430 Contents

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Table 430.7(B)

Code Letter A B C D E F G H J K

Electric Power Systems

Locked-Rotor Indicating Code Letters

Code Letter L M N P R S T U V Kilovolt-Amperes per Horsepower with Locked Rotor 9.0­9.99 10.0­11.19 11.2­12.49 12.5­13.99 14.0­15.99 16.0­17.99 18.0­19.99 20.0­22.39 22.4 and up

Durham

Kilovolt-Amperes per Horsepower with Locked Rotor 0­3.14 3.15­3.54 3.55­3.99 4.0­4.49 4.5­4.99 5.0­5.59 5.6­6.29 6.3­7.09 7.1­7.99 8.0­8.99

Table 430.52 Maximum Rating or Setting of Motor Branch-Circuit ShortCircuit and Ground-Fault Protective Devices

Percentage of Full-Load Current Dual Element Instantaneous Inverse Time (Time-Delay) Trip Breaker Breaker Fuse Single-phase motors 300 175 800 250 AC polyphase motors other than wound-rotor Squirrel cage 300 175 800 250 other than Design B energy-efficient Design B 300 175 1100 250 energy-efficient Synchronous 300 175 800 250 Wound rotor 150 150 800 150 Direct current 150 150 250 150 (constant voltage) Type of Motor Non-time Delay Fuse

Chapter 4

Table 430.91

NEC & NEMA Standards

Motor Controller Enclosure Selection

For Outdoor Use Enclosure Type Number1 3R 3S 3X 3RX 3SX 4 4X

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Provides a Degree of Protection Against the Following Environmental Conditions Incidental contact with the enclosed equipment Rain, snow, and sleet Sleet2 Windblown dust Hosedown Corrosive agents Temporary submersion Prolonged submersion

3

6

6P

X X -- X -- -- -- --

X X -- -- -- -- -- --

X X X X -- -- -- --

X X -- X -- X -- --

X X -- -- -- X -- --

X X X X -- X -- --

X X -- X X -- -- --

X X -- X X X -- --

X X -- X X -- X --

X X -- X X X X X

Provides a Degree of 1 12K 13 Protection Against the Following Environmental Conditions Incidental contact with the X X X X X X X X X X enclosed equipment Falling dirt X X X X X X X X X X Falling liquids and light -- X X X X X X X X X splashing Circulating dust, lint, -- -- X X -- X X X X X fibers, and flyings Settling airborne dust, lint, -- -- X X X X X X X X fibers, and flyings Hosedown and splashing -- -- X X -- X X -- -- -- water Oil and coolant seepage -- -- -- -- -- -- -- X X X Oil or coolant spraying -- -- -- -- -- -- -- -- -- X and splashing Corrosive agents -- -- -- X -- -- X -- -- -- Temporary submersion -- -- -- -- -- X X -- -- -- Prolonged submersion -- -- -- -- -- -- X -- -- -- 1Enclosure type number shall be marked on the motor controller enclosure. 2Mechanism shall be operable when ice covered. FPN: The term raintight is typically used in conjunction with Enclosure Types 3, 3S, 3SX, 3X, 4, 4X, 6, 6P. The term rainproof is typically used in conjunction with Enclosure Type 3R, 3RX. The term watertight is typically used in conjunction with Enclosure Types 4, 4X, 6, 6P. The term driptight is typically used in conjunction with Enclosure Types 2, 5, 12, 12K, 13. The term dusttight is typically used in conjunction with Enclosure Types 3, 3S, 3SX, 3X, 5, 12, 12K, 13.

For Indoor Use Enclosure Type Number1 2 4 4X 5 6 6P 12

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Table 430.248 Full-Load Currents in Amperes, SinglePhase Alternating-Current Motors

Horsepower ¼ ½ ¾ 1 1½ 2 3 5 7½ 10 115 Volts 4.4 5.8 7.2 9.8 13.8 16 20 24 34 56 80 100 200 Volts 2.5 3.3 4.1 5.6 7.9 9.2 11.5 13.8 19.6 32.2 46.0 57.5 208 Volts 2.4 3.2 4.0 5.4 7.6 8.8 11.0 13.2 18.7 30.8 44.0 55.0 230 Volts 2.2 2.9 3.6 4.9 6.9 8.0 10 12 17 28 40 50

Electric Power Systems

Durham

Table 430.250

Full-Load Current, Three-Phase Alternating-Current Motors

Induction-Type Squirrel Cage and Wound Rotor Synchronous-Type (Amperes) Unity Power Factor* (Amperes) Horse- 115 200 208 230 460 575 Volts 2300 230 460 575 2300 power Volts Volts Volts Volts Volts Volts Volts Volts Volts Volts ½ 4.4 2.5 2.4 2.2 1.1 0.9 -- -- -- -- -- ¾ 6.4 3.7 3.5 3.2 1.6 1.3 -- -- -- -- -- 1 8.4 4.8 4.6 4.2 2.1 1.7 -- -- -- -- -- 1½ 12.0 6.9 6.6 6.0 3.0 2.4 -- -- -- -- -- 2 13.6 7.8 7.5 6.8 3.4 2.7 -- -- -- -- -- 3 -- 11.0 10.6 9.6 4.8 3.9 -- -- -- -- -- 5 -- 17.5 16.7 15.2 7.6 6.1 -- -- -- -- -- 7½ -- 25.3 24.2 22 11 9 -- -- -- -- -- 10 -- 32.2 30.8 28 14 11 -- -- -- -- -- 15 -- 48.3 46.2 42 21 17 -- -- -- -- -- 20 -- 62.1 59.4 54 27 22 -- -- -- -- -- 25 -- 78.2 74.8 68 34 27 -- 53 26 21 -- 30 -- 92 88 80 40 32 -- 63 32 26 -- 40 -- 120 114 104 52 41 -- 83 41 33 -- 50 -- 150 143 130 65 52 -- 104 52 42 -- 60 -- 177 169 154 77 62 16 123 61 49 12 75 -- 221 211 192 96 77 20 155 78 62 15 100 -- 285 273 248 124 99 26 202 101 81 20 125 -- 359 343 312 156 125 31 253 126 101 25 150 -- 414 396 360 180 144 37 302 151 121 30 200 552 528 480 240 192 49 400 201 161 40 250 -- -- -- -- 302 242 60 -- -- -- -- 300 -- -- -- -- 361 289 72 -- -- -- -- 350 -- -- -- -- 414 336 83 -- -- -- -- 400 -- -- -- -- 477 382 95 -- -- -- -- 450 -- -- -- -- 515 412 103 -- -- -- -- 500 -- -- -- -- 590 472 118 -- -- -- -- *For 90 and 80 percent power factor, the figures shall be multiplied by 1.1 and 1.25, respectively.

Chapter 4

NEC & NEMA Standards

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Table 430.251(A) Conversion Table of Single-Phase Locked- Rotor Currents for Selection of Disconnecting Means and Controllers as Determined from Horsepower and Voltage Rating

Rated Horsepower ½ ¾ 1 1½ 2 3 5 7½ 10 Maximum Locked-Rotor Current in Amperes, Single Phase 115 Volts 208 Volts 230 Volts 58.8 32.5 29.4 82.8 45.8 41.4 96 53 48 120 66 60 144 80 72 204 113 102 336 186 168 480 265 240 600 332 300

Table 430.251(B) Conversion Table of Polyphase Design B, C, and D Maximum Locked-Rotor Currents for Selection of Disconnecting Means and Controllers as Determined from Horsepower and Voltage Rating and Design Letter

Rated Horsepower Maximum Motor Locked-Rotor Current in Amperes, Two- and Three-Phase, Design B, C, and D* 115 Volts 200 Volts 208 Volts 230 Volts 460 Volts 575 Volts B, C, D B, C, D B, C, D B, C, D B, C, D B, C, D ½ 40 23 22.1 20 10 8 ¾ 50 28.8 27.6 25 12.5 10 1 60 34.5 33 30 15 12 1½ 80 46 44 40 20 16 2 100 57.5 55 50 25 20 3 -- 73.6 71 64 32 25.6 5 -- 105.8 102 92 46 36.8 7½ -- 146 140 127 63.5 50.8 10 -- 186.3 179 162 81 64.8 15 -- 267 257 232 116 93 20 -- 334 321 290 145 116 25 -- 420 404 365 183 146 30 -- 500 481 435 218 174 40 -- 667 641 580 290 232 50 -- 834 802 725 363 290 60 -- 1001 962 870 435 348 75 -- 1248 1200 1085 543 434 100 -- 1668 1603 1450 725 580 125 -- 2087 2007 1815 908 726 150 -- 2496 2400 2170 1085 868 200 -- 3335 3207 2900 1450 1160 250 -- -- -- -- 1825 1460 300 -- -- -- -- 2200 1760 350 -- -- -- -- 2550 2040 400 -- -- -- -- 2900 2320 450 -- -- -- -- 3250 2600 500 -- -- -- -- 3625 2900 *Design A motors are not limited to a maximum starting current or locked rotor current.

These tables for use only with 430.110, 440.12, 440.41 and 455.8(C).

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Table 8 Conductor Properties

Electric Power Systems

Durham

Conductors Direct-Current Resistance at 75°C (167°F) Size Stranding Overall Copper Aluminum (AWG Area Quantity Diameter Diameter Area Uncoated Coated or mm2 Circular mm in. mm in. mm2 in.2 ohm/ ohm/ ohm/ ohm/ ohm/ ohm/ kcmil) mils km kFT km kFT km kFT 18 0.823 1620 1 -- -- 1.02 0.040 0.823 0.001 25.5 7.77 26.5 8.08 42.0 12.8 18 0.823 1620 7 0.39 0.015 1.16 0.046 1.06 0.002 26.1 7.95 27.7 8.45 42.8 13.1 16 1.31 2580 1 -- -- 1.29 0.051 1.31 0.002 16.0 4.89 16.7 5.08 26.4 8.05 16 1.31 2580 7 0.49 0.019 1.46 0.058 1.68 0.003 16.4 4.99 17.3 5.29 26.9 8.21 14 2.08 4110 1 -- -- 1.63 0.064 2.08 0.003 10.1 3.07 10.4 3.19 16.6 5.06 14 2.08 4110 7 0.62 0.024 1.85 0.073 2.68 0.004 10.3 3.14 10.7 3.26 16.9 5.17 12 3.31 6530 1 -- -- 2.05 0.081 3.31 0.005 6.34 1.93 6.57 2.01 10.45 3.18 12 3.31 6530 7 0.78 0.030 2.32 0.092 4.25 0.006 6.50 1.98 6.73 2.05 10.69 3.25 10 5.261 10380 1 -- -- 2.588 0.102 5.26 0.008 3.984 1.21 4.148 1.26 6.561 2.00 10 5.261 10380 7 0.98 0.038 2.95 0.116 6.76 0.011 4.070 1.24 4.226 1.29 6.679 2.04 8 8.367 16510 1 -- -- 3.264 0.128 8.37 0.013 2.506 0.764 2.579 0.786 4.125 1.26 8 8.367 16510 7 1.23 0.049 3.71 0.146 10.76 0.017 2.551 0.778 2.653 0.809 4.204 1.28 6 13.30 26240 7 1.56 0.061 4.67 0.184 17.09 0.027 1.608 0.491 1.671 0.510 2.652 0.808 4 21.15 41740 7 1.96 0.077 5.89 0.232 27.19 0.042 1.010 0.308 1.053 0.321 1.666 0.508 3 26.67 52620 7 2.20 0.087 6.60 0.260 34.28 0.053 0.802 0.245 0.833 0.254 1.320 0.403 2 33.62 66360 7 2.47 0.097 7.42 0.292 43.23 0.067 0.634 0.194 0.661 0.201 1.045 0.319 1 42.41 83690 19 1.69 0.066 8.43 0.332 55.80 0.087 0.505 0.154 0.524 0.160 0.829 0.253 1/0 53.49 105600 19 1.89 0.074 9.45 0.372 70.41 0.109 0.399 0.122 0.415 0.127 0.660 0.201 2/0 67.43 133100 19 2.13 0.084 10.62 0.418 88.74 0.137 0.3170 0.0967 0.329 0.101 0.523 0.159 3/0 85.01 167800 19 2.39 0.094 11.94 0.470 111.9 0.173 0.2512 0.0766 0.2610 0.0797 0.413 0.126 4/0 107.2 211600 19 2.68 0.106 13.41 0.528 141.1 0.219 0.1996 0.0608 0.2050 0.0626 0.328 0.100 250 127 -- 37 2.09 0.082 14.61 0.575 168 0.260 0.1687 0.0515 0.1753 0.0535 0.2778 0.0847 300 152 -- 37 2.29 0.090 16.00 0.630 201 0.312 0.1409 0.0429 0.1463 0.0446 0.2318 0.0707 350 177 -- 37 2.47 0.097 17.30 0.681 235 0.364 0.1205 0.0367 0.1252 0.0382 0.1984 0.0605 400 203 -- 37 2.64 0.104 18.49 0.728 268 0.416 0.1053 0.0321 0.1084 0.0331 0.1737 0.0529 500 253 -- 37 2.95 0.116 20.65 0.813 336 0.519 0.0845 0.0258 0.0869 0.0265 0.1391 0.0424 600 304 -- 61 2.52 0.099 22.68 0.893 404 0.626 0.0704 0.0214 0.0732 0.0223 0.1159 0.0353 700 355 -- 61 2.72 0.107 24.49 0.964 471 0.730 0.0603 0.0184 0.0622 0.0189 0.0994 0.0303 750 380 -- 61 2.82 0.111 25.35 0.998 505 0.782 0.0563 0.0171 0.0579 0.0176 0.0927 0.0282 800 405 -- 61 2.91 0.114 26.16 1.030 538 0.834 0.0528 0.0161 0.0544 0.0166 0.0868 0.0265 900 456 -- 61 3.09 0.122 27.79 1.094 606 0.940 0.0470 0.0143 0.0481 0.0147 0.0770 0.0235 1000 507 -- 61 3.25 0.128 29.26 1.152 673 1.042 0.0423 0.0129 0.0434 0.0132 0.0695 0.0212 1250 633 -- 91 2.98 0.117 32.74 1.289 842 1.305 0.0338 0.0103 0.0347 0.0106 0.0554 0.0169 1500 760 -- 91 3.26 0.128 35.86 1.412 1011 1.566 0.02814 0.00858 0.02814 0.00883 0.0464 0.0141 1750 887 -- 127 2.98 0.117 38.76 1.526 1180 1.829 0.02410 0.00735 0.02410 0.00756 0.0397 0.0121 2000 1013 -- 127 3.19 0.126 41.45 1.632 1349 2.092 0.02109 0.00643 0.02109 0.00662 0.0348 0.0106 Notes: 1. These resistance values are valid only for the parameters as given. Using conductors having coated strands, different stranding type, and, especially, other temperatures changes the resistance. 2. Formula for temperature change: R2 = R1 [1 + (T 2 - 75)] where cu = 0.00323, AL = 0.00330 at 75°C. 3. Conductors with compact and compressed stranding have about 9 percent and 3 percent, respectively, smaller bare conductor diameters than those shown. See Table 5A for actual compact cable dimensions. 4. The IACS conductivities used: bare copper = 100%, aluminum = 61%. 5. Class B stranding is listed as well as solid for some sizes. Its overall diameter and area is that of its circumscribing circle.

Chapter 4

NEC & NEMA Standards

11

Table 9 Alternating-Current Resistance and Reactance for 600-Volt Cables, 3-Phase, 60 Hz, 75°C (167°F) -- Three Single Conductors in Conduit

Ohms to Neutral per Kilometer Ohms to Neutral per 1000 Feet6 XL Alternating-Current Alternating-Current Effective Z Effective Z (Reactance) for Resistance for Resistance for at 0.85 PF for at 0.85 PF for Size All Wires Uncoated Copper Wires Aluminum Wires Uncoated Copper Wires Aluminum Wires Size (AWG PVC, Steel PVC Aluminum Steel PVC Aluminum Steel PVC Aluminum Steel PVC Aluminum Steel (AWG or Aluminum Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit Conduit or kcmil) Conduits kcmil) 14 0.190 0.240 10.2 10.2 10.2 -- -- -- 8.9 8.9 8.9 -- -- -- 14 0.058 0.073 3.1 3.1 3.1 -- -- -- 2.7 2.7 2.7 -- -- -- 12 0.177 0.223 6.6 6.6 6.6 10.5 10.5 10.5 5.6 5.6 5.6 9.2 9.2 9.2 12 0.054 0.068 2.0 2.0 2.0 3.2 3.2 3.2 1.7 1.7 1.7 2.8 2.8 2.8 10 0.164 0.207 3.9 3.9 3.9 6.6 6.6 6.6 3.6 3.6 3.6 5.9 5.9 5.9 10 0.050 0.063 1.2 1.2 1.2 2.0 2.0 2.0 1.1 1.1 1.1 1.8 1.8 1.8 8 0.171 0.213 2.56 2.56 2.56 4.3 4.3 4.3 2.26 2.26 2.30 3.6 3.6 3.6 8 0.052 0.065 0.78 0.78 0.78 1.3 1.3 1.3 0.69 0.69 0.70 1.1 1.1 1.1 6 0.167 0.210 1.61 1.61 1.61 2.66 2.66 2.66 1.44 1.48 1.48 2.33 2.36 2.36 6 0.051 0.064 0.49 0.49 0.49 0.81 0.81 0.81 0.44 0.45 0.45 0.71 0.72 0.72 4 0.157 0.197 1.02 1.02 1.02 1.67 1.67 1.67 0.95 0.95 0.98 1.51 1.51 1.51 4 0.048 0.060 0.31 0.31 0.31 0.51 0.51 0.51 0.29 0.29 0.30 0.46 0.46 0.46 3 0.154 0.194 0.82 0.82 0.82 1.31 1.35 1.31 0.75 0.79 0.79 1.21 1.21 1.21 3 0.047 0.059 0.25 0.25 0.25 0.40 0.41 0.40 0.23 0.24 0.24 0.37 0.37 0.37 2 0.148 0.187 0.62 0.66 0.66 1.05 1.05 1.05 0.62 0.62 0.66 0.98 0.98 0.98 2 0.045 0.057 0.19 0.20 0.20 0.32 0.32 0.32 0.19 0.19 0.20 0.30 0.30 0.30 1 0.151 0.187 0.49 0.52 0.52 0.82 0.85 0.82 0.52 0.52 0.52 0.79 0.79 0.82 1 0.046 0.057 0.15 0.16 0.16 0.25 0.26 0.25 0.16 0.16 0.16 0.24 0.24 0.25 1/0 0.144 0.180 0.39 0.43 0.39 0.66 0.69 0.66 0.43 0.43 0.43 0.62 0.66 0.66 1/0 0.044 0.055 0.12 0.13 0.12 0.20 0.21 0.20 0.13 0.13 0.13 0.19 0.20 0.20 2/0 0.141 0.177 0.33 0.33 0.33 0.52 0.52 0.52 0.36 0.36 0.36 0.52 0.52 0.52 2/0 0.043 0.054 0.10 0.10 0.10 0.16 0.16 0.16 0.11 0.11 0.11 0.16 0.16 0.16 3/0 0.138 0.171 0.253 0.269 0.259 0.43 0.43 0.43 0.289 0.302 0.308 0.43 0.43 0.46 3/0 0.042 0.052 0.077 0.082 0.079 0.13 0.13 0.13 0.088 0.092 0.094 0.13 0.13 0.14 4/0 0.135 0.167 0.203 0.220 0.207 0.33 0.36 0.33 0.243 0.256 0.262 0.36 0.36 0.36 4/0 0.041 0.051 0.062 0.067 0.063 0.10 0.11 0.10 0.074 0.078 0.080 0.11 0.11 0.11 250 0.135 0.171 0.171 0.187 0.177 0.279 0.295 0.282 0.217 0.230 0.240 0.308 0.322 0.33 250 0.041 0.052 0.052 0.057 0.054 0.085 0.090 0.086 0.066 0.070 0.073 0.094 0.098 0.10 300 0.135 0.167 0.144 0.161 0.148 0.233 0.249 0.236 0.194 0.207 0.213 0.269 0.282 0.289 300 0.041 0.051 0.044 0.049 0.045 0.071 0.076 0.072 0.059 0.063 0.065 0.082 0.086 0.088 350 0.131 0.164 0.125 0.141 0.128 0.200 0.217 0.207 0.174 0.190 0.197 0.240 0.253 0.262 350 0.040 0.050 0.038 0.043 0.039 0.061 0.066 0.063 0.053 0.058 0.060 0.073 0.077 0.080 400 0.131 0.161 0.108 0.125 0.115 0.177 0.194 0.180 0.161 0.174 0.184 0.217 0.233 0.240 400 0.040 0.049 0.033 0.038 0.035 0.054 0.059 0.055 0.049 0.053 0.056 0.066 0.071 0.073 500 0.128 0.157 0.089 0.105 0.095 0.141 0.157 0.148 0.141 0.157 0.164 0.187 0.200 0.210 500 0.039 0.048 0.027 0.032 0.029 0.043 0.048 0.045 0.043 0.048 0.050 0.057 0.061 0.064 600 0.128 0.157 0.075 0.092 0.082 0.118 0.135 0.125 0.131 0.144 0.154 0.167 0.180 0.190 600 0.039 0.048 0.023 0.028 0.025 0.036 0.041 0.038 0.040 0.044 0.047 0.051 0.055 0.058 750 0.125 0.157 0.062 0.079 0.069 0.095 0.112 0.102 0.118 0.131 0.141 0.148 0.161 0.171 750 0.038 0.048 0.019 0.024 0.021 0.029 0.034 0.031 0.036 0.040 0.043 0.045 0.049 0.052 1000 0.121 0.151 0.049 0.062 0.059 0.075 0.089 0.082 0.105 0.118 0.131 0.128 0.138 0.151 1000 0.037 0.046 0.015 0.019 0.018 0.023 0.027 0.025 0.032 0.036 0.040 0.039 0.042 0.046

Notes: 1. These values are based on the following constants: UL-Type RHH wires with Class B stranding, in cradled configuration. Wire conductivities are 100 percent IACS copper and 61 percent IACS aluminum, and aluminum conduit is 45 percent IACS. Capacitive reactance is ignored, since it is negligible at these voltages. These resistance values are valid only at 75°C (167°F) and for the parameters as given, but are representative for 600-volt wire types operating at 60 Hz. 2. Effective Z is defined as R cos() + X sin(), where is the power factor angle of the circuit. Multiplying current by effective impedance gives a good approximation for line-to-neutral voltage drop. Effective impedance values shown in this table are valid only at 0.85 power factor. For another circuit power factor (PF), effective impedance (Ze) can be calculated from R and XL values given in this table as follows: Ze = R × PF + XL sin[arccos(PF)].

12

Electric Power Systems

Durham

Table C.4 Maximum Number of Conductors or Fixture Wires in Intermediate Metal Conduit (IMC) (Based on Table 1, Chapter 9)

Size (AWG/ kcmil) 14 12 10 8 6 4 3 2 1 1/0 2/0 3/0 4/0 250 300 350 400 500 600 700 750 800 900 1000 1250 1500 1750 2000 14 12 10 8 14 12 10 8 6 4 3 2 1 1/0 2/0 3/0 4/0 250 300 350 400 500 600 700 750 CONDUCTORS Metric Designator (Trade Size) 35 41 53 63 (1¼) (1½) (2) (2½) 22 30 49 70 18 25 41 58 15 20 33 47 8 10 17 24 6 8 14 19 5 6 11 15 4 6 9 13 3 5 8 11 2 3 5 7 1 3 4 6 1 2 4 6 1 1 3 5 1 1 3 4 1 1 1 3 1 1 1 3 1 1 1 2 1 1 1 2 1 1 1 1 0 1 1 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 0 1 0 0 0 1 0 0 0 1 47 64 104 147 36 49 80 113 27 36 59 84 15 20 33 47 31 42 69 98 25 34 56 79 19 26 43 61 12 16 26 37 9 12 20 28 6 9 15 21 6 8 13 18 5 6 11 15 3 4 7 11 3 4 6 9 2 3 5 8 1 3 4 6 1 2 4 5 1 1 3 4 1 1 2 4 1 1 2 3 1 1 1 3 1 1 1 2 1 1 1 1 0 1 1 1 0 1 1 1

Type RHH, RHW, RHW-2

TW

RHH*, RHW*, RHW-2*, THHW, THW, THW-2

16 (½) 4 4 3 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 7 5 3 6 5 4 2 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0

21 (¾) 8 6 5 3 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 17 13 9 5 11 9 7 4 3 2 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0

27 (1) 13 11 8 4 3 3 2 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 27 21 15 8 18 14 11 7 5 4 3 3 1 1 1 1 1 1 1 1 0 0 0 0 0

78 (3) 108 89 72 38 30 23 21 18 12 10 9 7 6 5 4 4 3 3 2 2 1 1 1 1 1 1 1 1 228 175 130 72 151 122 95 57 43 32 28 23 16 14 12 10 8 7 6 5 4 4 3 3 2

91 (3½) 144 120 97 50 40 31 28 24 16 14 12 10 9 6 6 5 5 4 3 3 3 3 2 2 1 1 1 1 304 234 174 97 202 163 127 76 58 43 37 31 22 19 16 13 11 9 8 7 6 5 4 4 3

103 (4) 186 154 124 65 52 41 36 31 20 18 15 13 11 8 7 7 6 5 4 4 4 3 3 3 2 1 1 1 392 301 224 124 261 209 163 98 75 56 48 41 28 24 20 17 14 12 10 9 8 7 5 5 4

Chapter 4

800 900 1000 1250 1500 1750 2000 14 12 10 8 6 4 3 2 1 1/0 2/0 3/0 4/0 250 300 350 400 500 600 700 750 800 900 1000 14 12 10 8 6 4 3 2 1 1/0 2/0 3/0 4/0 14 12 10 8 6 4 3 2 1 14 12 10 8 6 4 3 0 0 0 0 0 0 0 14 10 6 3 2 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 13 10 7 4 3 1 1 1 1 1 1 0 0 16 11 7 4 3 1 1 1 1 10 7 5 3 1 1 1 0 0 0 0 0 0 0 24 17 11 6 4 3 2 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 23 17 12 7 5 3 3 2 1 1 1 1 1 28 20 12 7 5 3 2 1 1 17 13 9 5 4 3 2

NEC & NEMA Standards

0 0 0 0 0 0 0 39 29 18 10 7 4 4 3 2 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 38 28 20 11 8 5 4 4 2 1 1 1 1 46 32 20 12 9 6 4 3 3 27 21 15 8 6 4 4 0 0 0 0 0 0 0 68 49 31 18 13 8 6 5 4 3 3 2 1 1 1 1 1 1 1 1 1 0 0 0 66 48 34 19 14 10 8 6 4 4 3 2 1 79 56 34 21 15 10 7 6 5 47 36 27 15 11 8 7 1 1 0 0 0 0 0 91 67 42 24 17 10 9 7 5 4 4 3 2 1 1 1 1 1 1 1 1 1 1 1 89 65 46 26 19 13 11 9 6 5 4 3 3 107 76 46 29 20 14 10 8 7 64 49 36 20 15 11 9 1 1 1 1 1 0 0 149 109 68 39 28 17 15 12 9 8 6 5 4 3 3 2 2 1 1 1 1 1 1 1 145 106 76 43 31 21 18 15 10 8 7 6 5 175 124 76 48 33 23 17 14 11 104 80 59 33 24 18 15 1 1 1 1 1 1 1 211 154 97 56 40 25 21 17 13 11 9 7 6 5 4 4 3 3 2 1 1 1 1 1 205 150 107 61 44 30 25 21 14 12 10 8 7 247 175 107 68 47 33 24 20 16 147 113 84 47 35 25 21 2 2 1 1 1 1 1 326 238 150 86 62 38 32 27 20 17 14 12 9 8 7 6 5 4 3 3 3 3 2 2 317 231 166 95 67 47 39 32 22 19 15 13 10 381 271 166 105 73 50 37 30 25 228 175 130 72 53 39 33 3 3 3 1 1 1 1 436 318 200 115 83 51 43 36 27 23 19 16 13 10 9 8 7 6 5 4 4 4 3 3 423 309 221 127 90 63 52 43 30 25 21 17 14 510 362 221 140 98 67 49 41 33 304 234 174 97 71 52 44 4 4 3 3 2 1 1 562 410 258 149 107 66 56 47 35 29 24 20 17 13 12 10 9 7 6 5 5 5 4 4 545 398 285 163 116 81 68 56 39 32 27 22 18 657 466 285 180 127 87 63 53 43 392 301 224 124 92 67 56

13

THHN, THWN, THWN-2

FEP, FEPB, PFA, PFAH, TFE

PFA, PFAH, TFE

Z

XHH, XHHW, XHHW-2, ZW

14

2 1 1/0 2/0 3/0 4/0 250 300 350 400 500 600 700 750 800 900 1000 1250 1500 1750 2000 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Electric Power Systems

3 2 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 5 4 3 3 2 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 7 5 5 4 3 2 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 12 9 8 6 5 4 3 3 3 2 1 1 1 1 1 1 1 1 1 1 0 18 13 11 9 7 6 5 4 4 3 3 2 1 1 1 1 1 1 1 1 1 27 20 17 14 12 10 8 7 6 5 4 3 3 3 3 2 2 1 1 1 1 37 27 23 19 16 13 11 9 8 7 6 5 4 4 4 3 3 2 1 1 1 47 35 30 25 20 17 14 12 10 9 8 6 5 5 5 4 4 3 2 2 1

Durham

Chapter 4

NEC & NEMA Standards

15

NEMA Controller Size for Motors, Transformers, & Capacitors

Load Contin- Service Voltage uous Limit Current Current Motor Maximum Non-plugging and Non-jogging Duty NEMA Size 00 V 115 200 230 380 460 575 115 200 230 380 460 575 115 200 230 380 460 575 115 230 115 200 230 380 460 575 115 200 230 380 460 575 115 200 230 380 460 575 115 200 230 380 460 575 115 200 230 380 460 575 230 460 575 230 460 575 230 460 575 Amp 9 Amp 11 HP 1 1/3 -- 1 -- -- -- 1 -- 2 -- -- -- 2 -- 3 -- -- -- 3 5 3 -- 7-1/2 -- -- -- 7-1/2 -- 15 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- HP 3 -- 1-1/2 1-1/2 1-1/2 2 2 -- 3 3 5 5 5 -- 7-1/2 7-1/2 10 10 10 -- -- -- 10 15 25 25 25 -- 25 30 50 50 50 -- 40 50 75 100 100 -- 75 100 150 200 200 -- 150 200 300 400 400 300 600 600 450 900 900 800 1600 1600 Motor Maximum Plugging and Jogging Duty HP 1 1/4 -- 1/2 -- -- -- 1/2 -- 1 -- -- -- 1 -- 2 -- -- -- 1-1/2 3 2 -- 5 -- -- -- 7-1/2 -- 15 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- HP 3 -- 1 1 1 1-1/2 1-1/2 -- 1-1/2 1-1/2 1-1/2 2 2 -- 3 3 5 5 5 -- -- -- 7-1/2 10 15 15 15 -- 15 20 30 30 30 -- 25 30 50 60 60 -- 60 75 125 150 150 -- 125 150 250 300 300 -- -- -- -- -- -- -- -- -- Transformer Transformer Capacitor Circuit Primary Primary Switching Closing Switching Switching Maximum Inrush Current Inrush Current Inrush Current < = 20 times = 20 to 40 times Peak Including Continuous Amp Continuous Amp Offset kVA kVA kVA kVA kVAR Amp 1 3 1 3 3 3 -- -- -- -- -- 87 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 0.6 -- 0.3 -- -- 140 -- 1.8 -- 0.9 -- 1.2 2.1 0.6 1 -- -- -- -- -- -- 2.4 4.2 1.2 2.1 -- 3 5.2 1.5 2.6 -- 1.2 -- 0.6 -- -- 288 -- 3.6 -- 1.8 -- 2.4 4.3 1.2 2.1 6 -- -- -- -- -- 4.9 8.5 2.5 4.3 13.5 6.2 11 3.1 5.3 17 -- -- -- -- -- -- -- -- -- -- -- -- 2.1 -- 1 -- -- 483 -- 6.3 -- 3.1 -- 4.1 7.2 2.1 3.6 12 -- -- -- -- -- 8.3 14 4.2 7.2 25 10 18 5.2 8.9 31 4.1 -- 2 -- -- 947 -- 12 -- 6.1 -- 8.1 14 4.1 7.0 27 -- -- -- -- -- 16 28 8.1 14 53 20 35 10 18 67 6.8 -- 3.4 -- -- 1581 -- 20 -- 10 -- 14 23 6.8 12 40 -- -- -- -- -- 27 47 14 23 80 34 59 17 29 100 14 -- 6.8 -- -- 3163 -- 41 -- 20 -- 27 47 14 24 80 -- -- -- -- -- 54 94 27 47 160 68 117 34 59 200 27 -- 14 -- -- 6326 -- 81 -- 41 -- 54 94 27 47 160 -- -- -- -- -- 108 188 54 94 320 135 234 68 117 400 -- -- -- -- 240 9470 -- -- -- -- 480 -- -- -- -- 600 -- -- -- -- 360 14205 -- -- -- -- 720 -- -- -- -- 900 -- -- -- -- 665 25380 -- -- -- -- 1325 -- -- -- -- 1670

0

18

21

1

27

32

1P 2

36 45

42 52

3

90

104

4

135

156

5

270

311

6

540

621

7 8 9

810 1215 2250

932 1400 2590

16

Electric Power Systems

Durham

Service-Limit Current Ratings - The service-limit current ratings shown represent the maximum rms current, in amperes, which the controller shall be permitted to carry for protracted periods in normal service. At service-limit current ratings, temperature rises shall be permitted to exceed those obtained by testing the controller at its continuous current rating. The current rating of overload relays or the trip current of other motor protective devices used shall not exceed the service-limit current rating of the controller. Plugging or Jogging Service - The listed horsepower ratings are recommended for those applications requiring repeated interruption of stalled motor current encountered in rapid motor reversal in excess of five openings or closings per minute and shall not be more than ten in a ten minute period. Capacitor terminals - If maximum available current is greater than 3,000 amperes, consult NEMA ICS-2 Standard.

Chapter 4

NEC & NEMA Standards

17

NEMA Table 11 Typical Characteristics and Applications of Fixed Frequency Small and Medium AC Squirrel-Cage Induction Motors

Design Letter Locked Rotor Torque Polyphase Percent Characteristics Rated Load Torque* 70-275 Design A High locked rotor torque High locked rotor current 70-275 Design B Normal locked rotor torque Normal locked rotor current Design C High locked rotor torque Normal locked rotor current Design D High locked rotor torque High slip Design N Small motor Design 0 Small motor Design L Medium motor Design M Medium motor *Higher values are for motors having lower horsepower ratings. 100% NA Pullup Torque Percent Rated Load Torque 65-190 Breakdown Torque Percent Rated Load Torque 175-300 Locked Slip Typical Applications Rotor Current Percent Percent Rated Sync Load Speed Current Not 0.5-5% Fans, blowers, centrifugal pumps defined and compressors, motor-generator sets, etc., where starting torque requirements are relatively low. Relative Efficiency

Medium or high

65-190 175-300 600-700 0.5-5% Fans, blowers, centrifugal pumps and compressors, motor-generator sets, etc., where starting torque requirements are relatively low. 1-5%

Medium or high

200-285 140-195 190-225 600-700

Conveyors, crushers, stirring motors, Medium agitators, reciprocating pumps and compressors, etc., where starting under load is required High peak loads with or without flywheels such as punch presses, shears, elevators, extractors, winches, hoists, oil-well pumping and wire-drawing motors Centrifugal loads where starting torque requirements are relatively low. Low

275

NA

275

600-700

5-8%

-

NA NA 100%

-

-

NA NA

Low

Fans, blowers, centrifugal pumps and compressors, motor-generator sets, etc., where starting torque requirements are relatively low. Fans, blowers, centrifugal pumps and compressors, motor-generator sets, etc., where starting torque requirements are relatively low.

Medium or low Medium or low

18 NEMA MOTOR DIMENSIONS

Shaft ­ Key Dimensions

NEMA Shaft (U) 3/8 1/2 5/8 7/8 1-1/8 1-3/8 1-5/8 1-7/8 2-1/8 2-3/8 2-1/2 2-7/8 3-3/8 3-7/8 Key (R) 21/64 29/64 33/64 49/64 63/64 1-13/64 1-13/32 1-19/32 1-27/32 2-1/64 2-3/16 2-29/64 2-7/8 3-5/16 Dimen (S) flat flat 3/16 3/16 1/4 5/16 3/8 1/2 1/2 5/8 5/8 3/4 7/8 1

Electric Power Systems

Durham

Frame Dimensions

Frame D

42 48 56 56H 143T 145T 182 184 182T 184T 213 215 213T 215T 254U 256U 254T 256T 284U 286U 284T 286T 284TS 286TS 324U 326U 324T 326T 324TS 326TS 364U 365U 364T 365T 364TS 365TS 404U 405U 404T 405T 404TS 405TS 444U 445U 444T 445T 447T 449T 444TS 445TS 447TS 449TS

E

2F

H

N*

1-1/2 1-7/8 2-7/16 2-1/8 2-1/2 2-11/16 2-11/16 3-9/16 3-9/16 3-1/2 3-1/2 3-7/8 3-7/8 4-1/16 4-1/16 4-5/16 4-5/16 5-1/8 5-1/8 4-7/8 4-7/8 3-3/8 3-3/8 5-7/8 5-7/8 5-1/2 5-1/2 3-15/16 3-15/16 6-3/4 6-3/4 6-1/4 6-1/4 4 4 7-3/16 7-3/16 7-5/16 7-5/16 4-1/2 4-1/2 8-5/8 8-5/8 8-1/2 8-1/2 8-15/16 8-15/16 5-3/16 5-3/16 4-15/16 4-15/16

O*

5 5-7/8 6-7/8 6-7/8 8-11/16

P*

4-11/16 5-11/16 6-5/8 6-5/8 7-7/8

U

3/8 1/2 5/8 7/8

V

1-1/8 1-1/2 1-7/8 2-1/4 2-1/4 2-1/4 2-3/4 2-3/4 3 3 3-3/8 3-3/8 3-3/4 3-3/4 4 4 4-7/8 4-7/8 4-5/8 4-5/8 3-1/4 3-1/4 5-5/8 5-5/8 5-1/4 5-1/4 3-3/4 3-3/4 6-3/8 6-3/8 5-7/8 5-7/8 3-3/4 3-3/4 7-1/8 7-1/8 7-1/4 7-1/4 4-1/4 4-1/4 8-5/8 8-5/8 8-1/2 8-1/2 8-1/2 8-1/2 4-3/4 4-3/4 4-3/4 4-3/4

AA

3/8 1/2 1/2 3/4 3/4

AB*

AH

AJ

AK

3 3 4-1/2 4-1/2 4-1/2 4-1/2 8-1/2 8-1/2 8-1/2

BA

2-1/16 2-1/2 2-3/4 2-1/4 2-3/4

BB

1/8 1/8 1/8 1/8 1/8 1/8 1/4 1/4 1/4

BD*

4-5/8 5-5/8 6-1/2 6-1/2 6-1/2 6-1/2 9 9 9

TAP

1/4-20 1/4-20 3/8-16 3/8-16 3/8-16 3/8-16 1/2-13 1/2-13 1/2-13

2-5/8 1-3/4 1-11/16 9/32 slot 3 2-1/8 2-3/4 11/32 slot 3-1/2 2-7/16 3 11/32 slot 5 3-1/2 2-3/4 4 11/32 5 4-1/2 4-1/2 3-3/4 5-1/2 13/32 4-1/2 5-1/2 5-1/2 5-1/4 4-1/4 7 13/32 5-1/2 7 8-1/4 6-1/4 5 10 17/32 8-1/4 10 9-1/2 11 7 5-1/2 9-1/2 17/32 11 9-1/2 11 10-1/2 12 8 6-1/4 10-1/2 21/32 12 10-1/2 12 11-1/4 12-1/4 9 7 11-1/4 21/32 12-1/4 11-1/4 12-1/4 12-1/4 13-3/4 10 8 12-1/4 13/16 13-3/4 12-1/4 13-3/4 14-1/2 16-1/2 14-1/2 11 9 16-1/2 13/16 20 25 14-1/2 16-1/2 20 25

4-1/32 1-5/16 3-3/4 4-3/8 1-11/16 3-3/4 5 2-1/16 5-7/8 5-1/4 5-7/8 2-1/8 2-1/8 2-1/8 2-5/8 2-5/8 2-3/4 2-3/4 3-1/8 3-1/8 3-1/2 3-1/2 3-3/4 3-3/4 4-5/8 4-5/8 4-3/8 4-3/8 3 3 5-3/8 5-3/8 5 5 3-1/2 3-1/2 6-1/8 6-1/8 5-5/8 5-5/8 3-1/2 3-1/2 6-7/8 6-7/8 7 7 4 4 8-3/8 8-3/8 8-1/4 8-1/4 8-1/4 8-1/4 4-1/2 4-1/2 4-1/2 4-1/2 5-7/8 5-7/8 5-7/8 7-1/4 7-1/4 7-1/4

7/8 7/8 1-1/8 1-1/8 1-1/8 10-1/4 9-9/16 1-1/8 1-3/8 1-3/8 1-3/8 12-7/8 12-15/16 1-3/8 1-5/8 1-5/8 1-5/8 1-5/8 14-5/8 14-5/8 1-7/8 1-7/8 1-5/8 1-5/8 1-7/8 1-7/8 2-1/8 16-1/2 16-1/2 2-1/8 1-7/8 1-7/8 2-1/8 2-1/8 18-1/2 18-1/4 2-3/8 2-3/8 1-7/8 1-7/8 2-3/8 2-3/8 20-5/16 20-1/8 2-7/8 2-7/8 2-1/8 2-1/8 22-7/8 22-3/8 2-7/8 22-7/8 22-3/8 2-7/8 22-7/8 22-3/8 3-3/8 22-7/8 22-3/8 3-3/8 22-15/16 22-3/4 3-3/8 22-15/16 22-3/4 3-3/8 22-7/8 22-3/8 2-3/8 22-7/8 22-3/8 2-3/8 22-15/16 22-3/4 2-3/8 22-15/16 22-3/4 2-3/8

3/4

7-3/8

3-1/2

1

9-5/8

7-1/4

8-1/2

4-1/4

1/4

10

1/2-13

1-1/2

13-1/8

9

10-1/2

4-3/4

1/4

11-1/4 1/2-13

2

14-1/8

11

12-1/2

5-1/4

1/4

13-3/8 5/8-11

2-1/2 15-1/16

11

12-1/2

5-7/8

1/4

13-3/8 5/8-11

3

18

11

12-1/2

6-5/8

1/4

13-7/8 5/8-11

19-9/16 19-9/16 19-9/16 19-9/16 3 21-11/16 21-11/16 19-9/16 19-9/16 4NPT 21-11/16 4NPT 21-11/16

14

16

7-1/2

1/4

16-3/4 5/8-11

Chapter 4 NEMA MOTOR DIMENSIONS ­ 2

Frame Size Information

NEC & NEMA Standards

Notes From Front:

19

Suffix letters after the NEMA frame size indicates that the frame differs in some way from the standard frame. Below is a list of suffixes that may be found after the frame size and their definition. A DC Motor or Generator C "C" flange mounting on drive end ** D "D" flange mounting on drive end ** E Shaft dimensions for elevator motors in frames larger than the 326U frame H Frame with an "F" dimension larger than a frame without (small framed motors) J Jet pump motors JM "C"-face mounted close coupling pump with mechanical seal JP "C"-face mounted close coupling pump -packed pump K Sump pump motor LP & LPH "P" flange mounting vertical solid shaft pump P & PH "P" flange mounting vertical hollow shaft pump S Standard short shaft T Included as part of a frame number-standard dimension U Included as part of a frame number-standard dimension V Vertical mounting Y Special mounting dimensions -manufactured specified Z Special shaft dimensions -manufactured specified ** If the face mounting is on the end opposite the drive, the suffix will be as follows: "FC" or "FD"

-When a "C" flange has been added to a NEMA motor the "BA" dimensions are: Frame: "BA": 143-5TC 2-3/4 182-4TC 3-1/2 213-5TC 4-1/4 254-6TC 4-3 4 -Dimensions: C, N, O, P, & AB are specific to each manufacturer. Please call for exact dimensions.

Assembly Position F-1 VS. F-2 F-1 F-2

Pre-NEMA Dimensions

FRAME 203 204 224 225 254 284 324 324S 326 326S 364 364S 356 365S U 3/4 3/4 1 1 1-1/8 1-1/4 1-5/8 1-5/8 1-5/8 1-5/8 1-7/8 1-7/8 1-7/8 1-5/8 V 2 2 2-3/4 2-3/4 3-1/8 3-3/4 4-5/8 3 4-5/8 3 5-3/8 3-1/2 5-3/8 3-1/2 D 5 5 5-1/2 5-1/2 6-1/4 7 8 8 8 8 9 9 9 9 2F 5-1/2 6-1/2 6-3/4 7-1/2 8-1/14 9-1/2 10-1/2 10-1/2 12 12 11-1/4 11-1/4 12-1/4 12-1/4 E 4 4 4-1/2 4-1/2 5 5-1/2 6-1/4 6-1/4 6-1/4 6-1/4 7 7 7 7 FRAME 404 404S 405 405S 444 444S 445 445S 504 504S 505 505S 584 584S U 2-1/8 1-7/8 2-1/8 1-7/8 2-3/8 2-1/8 2-3/8 2-1/8 2-5/8 2-1/8 2-7/8 2-1/8 2-7/8 2-3/8 V 6-1/8 3-1/2 6-1/8 3-/2 6-7/8 4 6-7/8 4 7-5/8 4 8-3/8 4 11-5/8 4-3/4 D 10 10 10 10 11 11 11 11 12-1/2 12-1/2 12-1/2 12-1/2 14-1/2 14-1/2 2F 12-1/4 12-1/4 13-3/4 13-3/4 14-1/2 14-1/2 16-1/2 16-1/2 16 16 18 18 18 18 E 8 8 8 8 9 9 9 9 8 8 9 9 9 9

Standard NEMA Frames vs Horsepower

HP T-Frame 1964Present 1 182T 1.5 184T 2 213T 3 215T 5 254T 7.5 256T 10 284T 15 286T 20 324T 25 326T 30 364T 40 365T 50 404T 60 405T 75 444T 100 445T 125 . 150 . 200 . 250 . 900 RPM U-Frame 1952Present 213 213 215 254U 256U 284U 286U 326U 364U 365U 404U 405U 444U 445U . . . . . . 1200 RPM Original T-Frame U-Frame NEMA 19641952Present Present 225 145T 184 254 182T 184 254 184T 213 284 213T 215 324 215T 254U 326 254T 256U 364 256T 284U 365 284T 324U 404 286T 326U 405 324T 364U 444 324T 365U 445 364T 404U 504 365T 405U 505 404T 444U . 405T 445U . 444T . . 445T . . .. . . . . . . Original T-Frame NEMA 1964Present 204 143T 224 145T 225 145T 254 182T 284 184T 324 213T 326 215T 364 254T 365 256T 404 284T 405 286T 444 324T 445 326T 504 364TS 505 365TS . 404TS/405TS . 405TS/444TS . 444TS/445TS . 455TS . . 1800 RPM U-Frame 1952Present 182 184 184 213 215 254U 256U 284U 286U 324U 326U 364U 365US 404US/405US 405US/444US 444US/445US 445US . . . T-Frame 1964Present 203 . 204 143T 224 145T 225 145T/182T 254 182T/184T 284 184T/213T 324 213T/215T 326 215T/254T 364 254T/256T 364/365 256T/284TS 365/404 284TS/286TS 404/405 286TS/324TS 405S/444 324TS/326TS 444S/445S 326TS/364TS 445S/504S 364TS/365TS 504S/505S 365TS/405TS 505S 404TS/444TS . 405TS/445TS . 444TS . 445TS Original NEMA 3600 RPM U-Frame 1952Present . 182 184 184 213 215 254U 256U 284U/286U 286U/324U 324S/326S 326S/364US 364US 365US/405US 404US/444US 405US/445US 444US 445US . . Original NEMA . 203 204 224 225 254 284 324 326 364S/365S 364S/404S 365S/405S 404S/444S 405S/445S 444S/504S 445S/505S 504S 505S . .

These charts are provided for reference use only. We are not responsible for any printing errors.

20

NEMA Motor Enclosure Type

Abbreviation ODG ODG-FV ODG-SV ODP Totally Enclosed TEAO TEBC TECACA TEDC-A/A TEDC-A/W TEFC TENV TETC TEWAC TEXP Weather Protected WPI WPII Special XE XL XP XT IEC IP-22 IP-44 IP-54 IP-55 Type Open Drip Proof

Electric Power Systems

Durham

Description Open Drip-Proof, Guarded Open Drip-Proof, Force Ventilated Open Drip-Proof, Separately Ventilated Open Drip-Proof Totally-Enclosed, Air-Over Totally-Enclosed, Blower-Cooled Totally-Enclosed, Closed Circuit,, Air to Air Totally-Enclosed, Dual Cooled, Air to Air Totally-Enclosed, Dual Cooled, Air to Water Totally-Enclosed, Fan-Cooled Totally-Enclosed Non-Ventilated Totally-Enclosed, Tube Cooled Totally-Enclosed, Water/Air Cooled Totally-Enclosed, Explosion-Proof Weather Protected, Type I Weather Protected Type II Premium Efficient Extra Life Explosion-Proof Extra Tough Dust ignition proof Open Drip-Proof Totally-Enclosed Splash Proof Washdown

Designed for use in non-hazardous, relatively clean areas, most common type, extremely wet, dirty, or dusty areas

adverse outdoor conditions improved efficiency withstanding an explosion of a specified dust, gas, or vapor preventing the ignition of a dust, gas, or vapor surrounding the motor representative IEC designations

Chapter 4

NEC & NEMA Standards

21

Electrical Power System Design Example

Pump: Motor: Power: 20 Hp, 300 RPM, 18" sheave 3, 460 V 3, 7200 LN Pump: Motor: Power: Environment: Example Factor F 5.59 112,000/1.732*460 1.25*27 + 0 0.91 800 instant 105 120*60/4 2% U 300*18/1800 3 + N 1/2 1.732*480*27/1000 Example Result 20 27 112 141 145 34 THHN 90C 10 AWG 36 216 200 3R 2 483 28.4 TEFC B 1800 1764 256T 1-5/8 3" 4 3/4 22.5 3 ­ 7.5 277 / 480 Y 12470 two 2-1/2 + Problem Factor Problem Result

Environment: ambient 98F, outdoor # Measure Parameter 1 Motor horsepower 2 Full load Amps - FLA 3 Lock letter code & kVA/hp 4 Lock rotor amp calculate Standard Table or Reference NEC 430.250 NEC 430.250 NEC 430.7(B) kVA*1000/1.732 V

5 Lock rotor amp for disconnect NEC 430.251(B) 6 Wire rating:1.25*largest+other NEC 430.24 7 Insulation type 8 Insulation temperature 9 AWG / kcmil 10 Temperature correction amp 11 Max breaker rating & type 12 Actual breaker size 13 Controller enclosure 14 Controller size 15 Controller max closing amp 16 Overload setting % - Amp 17 Motor enclosure 18 Motor NEMA design 19 Motor sync speed 20 Motor slip - shaft speed 21 Motor frame 22 Shaft diameter 23 Sheave diameter 24 # wires 25 Conduit type & size 26 Total kVA 26 Transformer kVA size 28 Secondary volt & Y- 29 Primary volt & Y- 30 Transformers taps 31 Transformer impedance PU NEMA 11 120 * freq / poles NEMA 11 NEMA Dimension 2 NEMA Dimensions P(n*dia) = M(n*dia) NEC C4 et al 1.732 V * I / 1000 NEMA NEC 310-16 NEC 310-16 NEC 310-16 NEC 310-16 NEC 430.52 NEC 240.6(A) NEC 430.91 NEMA Controller NEMA Controller NEMA Enclosure

Information

National Electrical Code

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