Federal regulations · Through 2026-08-25 · Newer source version available

30 CFR Appendix I to Subpart D of Part 18: Appendix I to Subpart D of Part 18

LIST OF TABLES
Table No. Title
1 Portable power cable ampacities—600 volts.
2 Portable cord ampacities—600 volts.
3 Portable power cable ampacities—601 to 5,000 volts.
4 Normal diameter of round cables with tolerances in inches—600 volts.
5 Nominal dimension of flat cables with tolerances in inches—600 volts.
6 Nominal diameter of heavy jacketed cords with tolerances in inches—600 volts.
7 Nominal diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts.
8 Fuse ratings or instantaneous settings of circuit breakers for short-circuit protection of portable cables.
9 Specifications for portable cables longer than 500 feet.
10 High voltage trailing cable ampacities and outside diameters.
Table 1—Portable Power Cable Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient)
Conductor size—AWG or MCM Single conductor 2-conductor, round or flat 3-conductor, round or flat 4-conductor 5-conductor 6-conductor
8 45 40 35 30 25 20
6 60 50 50 40 35 30
4 85 70 65 55 45 35
3 95 80 75 65 55 45
2 110 95 90 75 65 55
1 130 110 100 85 75 65
1/0 150 130 120 100 90 80
2/0 175 150 135 115 105 95
3/0 205 175 155 130 120 110
4/0 235 200 180 150 140 130
250 275 220 200 160
300 305 240 220 175
350 345 240 235 190
400 375 280 250 200
450 400 300 270 215
500 425 320 290 230
Table 2—Portable Cord Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient)
Conductor size—AWG 1-3 conductor 4-6 conductor 7-9 conductor
14 15 12 8
12 20 16 11
10 25 20 14
Table 3—Portable Power Cable Ampacities—601 to 5,000 Volts (Amperes Per Conductor Based on 75 °C. Copper Temperature—40 °C. Ambient)
Conductor size—AWG or MCM 3-conductor types G-GC and SIIC-GC 2,000 volts 3-conductor type SHD-GC 2,001-5,000 volts
6 65 65
4 85 85
3 100 100
2 115 115
1 130 130
1/0 145 145
2/0 170 170
3/0 195 195
4/0 220 220
250 245 245
300 275 275
350 305 305
Table 4—Nominal Diameters of Round Cables With Tolerances in Inches—600 Volts
Conductor size—AWG or MCM Single conductor 2-conductor 3-conductor 4-conductor—Types W & G 5-conductor—Types W & G 6-conductor
Types W & G twisted Type PG, 2 power Type PCG, 3 power, ground Types W & G Type PG, 3 power, ground Type PCG, 3 power, 2 control, ground Type w Tolerance
8 0.44 0.81 0.84 0.94 0.91 0.93 1.03 0.99 1.07 1.18 ±0.03
6 .51 .93 .93 .98 1.01 1.03 1.18 1.10 1.21 1.31 ±.03
4 .57 1.08 1.08 1.10 1.17 1.20 1.29 1.27 1.40 1.52 ±.03
3 .63 1.17 1.17 1.20 1.24 1.27 1.31 1.34 1.48 1.61 ±.03
2 .66 1.27 1.27 1.29 1.34 1.34 1.39 1.48 1.61 1.75 ±.03
1 .74 1.44 1.44 1.44 1.51 1.52 1.52 1.68 1.88 2.05 ±.03
1/0 .77 1.52 1.52 1.52 1.65 1.68 1.68 1.79 1.96 2.13 ±.04
2/0 .82 1.65 1.65 1.65 1.75 1.79 1.79 1.93 2.13 2.32 ±.04
3/0 .87 1.77 1.77 1.77 1.89 1.93 1.93 2.07 2.26 2.49 ±.05
4/0 .93 1.92 1.92 1.92 2.04 2.13 2.13 2.26 2.46 2.71 ±.05
250 1.03 2.16 2.16 2.16 2.39 2.39 2.39 2.66 ±.06
300 1.09 2.32 2.56 2.84 ±.06
350 1.15 2.43 2.68 2.98 ±.06
400 1.20 2.57 2.82 3.14 ±.06
450 1.26 2.67 2.94 3.26 ±.06
500 1.31 2.76 3.03 3.40 ±.06
Table 5—Nominal Dimensions of Flat Cables With Tolerances in Inches—600 Volts
Conductor size—AWG 2-conductor 3-conductor—Type G
Type W Type G Major Minor
Major Minor Major Minor O.D. Tolerance O.D. Tolerance
O.D. Tolerance O.D. Tolerance O.D. Tolerance O.D. Tolerance
8 0.84 ±0.04 0.51 ±0.03
6 .93 ±.04 .56 ±.03 1.02 ±.04 0.56 ±.03 1.65 ±0.06 0.67 ±0.05
4 1.05 ±.04 .61 ±.03 1.15 ±.04 .61 ±.03 1.85 ±.06 .75 ±.05
3 1.14 ±.04 .68 ±.03 1.26 ±.04 .68 ±.03 1.99 ±.06 .77 ±.05
2 1.24 ±.04 .73 ±.03 1.35 ±.04 .73 ±.06 2.10 ±.06 .81 ±.05
1 1.40 ±.04 .81 ±.03 1.55 ±.04 .81 ±.03 2.43 ±.06 .97 ±.05
1/0 1.51 ±.04 .93 ±.03 1.67 ±.04 .93 ±.03
2/0 1.63 ±.04 .99 ±.03 1.85 ±.04 .99 ±.03
3/0 1.77 ±.04 1.03 ±.03 2.00 ±.04 1.03 ±.03
4/0 1.89 ±.04 1.10 ±.03 2.10 ±.04 1.10 ±.03
Table 6—Nominal Diameters of Heavy Jacketed Cords With Tolerances In Inches—600 Volts
Conductor size—AWG 2-conductor 3-conductor 4-conductor 5-conductor 6-conductor 7-conductor
Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance
14 0.64 ±0.02 0.67 ±0.02 0.71 ±0.02 0.78 ±0.03 0.83 ±0.03 0.89 ±0.03
12 .68 ±.02 .72 ±.03 .76 ±.03 .83 ±.03 .89 ±.03 .98 ±.03
10 .73 ±.03 .80 ±.03 .84 ±.03 .90 ±.03 1.00 ±.03 1.07 ±.03
Table 7—Nominal Diameters of Three-Conductor Portable Power Cables With Tolerances in Inches—601 to 5,000 Volts
Conductor size—AWG or MCM Type G-GC (nonshielded) 2,000 volts Type SHC-GC (shielded overall) 2,000 volts Type SHD-GC (individually shielded power conductors) 2,001-3,000 volts Type SHD-GC (individually shielded power conductors) 3,001-5,000 volts
Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance
6 1.25 + 0.10, −0.06 1.39 + 0.11, −0.07 1.62 + 0.13, −0.08 1.78 + 0.14, −0.09
4 1.40 + .11, −.07 1.55 + .12, −.08 1.77 + .14, −.09 1.90 + .15, −.10
3 1.48 + .12, −.07 1.62 + .13, −.08 1.84 + .15, −.09 1.98 + .16, −.10
2 1.55 + .12, −.08 1.71 + .14, −.09 1.92 + .15, −.10 2.09 + .17, −.11
1 1.74 + .14, −.09 1.89 + .15, −.09 2.04 + .16, −.10 2.18 + .17, −.11
1/0 1.84 + .15, −.09 2.02 + .16, −.10 2.18 + .17, −.11 2.34 + .19, −.12
2/0 1.99 + .16, −.10 2.16 + .17, −.11 2.29 + .18, −.12 2.46 + .20, −.12
3/0 2.12 + .17, −.11 2.30 + .18, −.11 2.45 + .20, −.12 2.62 + .21, −.13
4/0 2.30 + .18, −.12 2.48 + .20, −.12 2.62 + .21, −.13 2.76 + .22, −.14
250 2.46 + .20, −.12 2.70 + .22, −.13
300 2.63 + .21, −.13 2.84 + .23, −.14
350 2.75 + .22, −.14 2.97 + .24, −.15
Table 8—Fuse Ratings or Instantaneous Setting of Circuit Breakers for Short-Circuit Protection of Portable Cables and Cords
Conductor size—AWG or MCM Ohms/1,000 ft. at 25 °C. Maximum allowable fuse rating (amperes) Maximum allowable circuit breaker instantaneous setting (amperes) 1
14 2.62 20 50
12 1.65 30 75
10 1.04 40 150
8 .654 80 200
6 .410 100 300
4 .259 200 500
3 .205 250 600
2 .162 300 800
1 .129 375 1,000
1/0 .102 500 1,250
2/0 .081 1,500
3/0 .064 2,000
4/0 .051 2,500
250 .043 2,500
300 .036 2,500
350 .031 2,500
400 .027 2,500
450 .024 2,500
500 .022 2,500
1 Higher circuit-breaker settings may be permitted for special applications when justified.
Table 9—Specifications for Portable Cables Longer Than 500 Feet 1
Conductor size—AWG or MCM Max. allowable length (feet) Normal ampacity at 60 °C. copper temperature (40 °C. ambient) Resistance at 60 °C. copper temperature (ohms)
6 550 50 0.512
4 600 70 .353
3 650 80 .302
2 700 95 .258
1 750 110 .220
1/0 800 130 .185
2/0 850 150 .157
3/0 900 175 .130
4/0 1,000 200 .116
250 1,000 220 .098
300 1,000 240 .082
350 1,000 260 .070
400 1,000 280 .061
450 1,000 300 .054
500 1,000 320 .050
1 Fuses shall not be used for short-circuit protection of these cables. Circuit breakers shall be used with the instantaneous trip settings not to exceed the values given in Table 8.
Table 10—High Voltage Trailing Cable Ampacities and Outside Diameters
Power conductor Ampacity * Outside diameter ** (inches)
Size AWG or kcmil Amperes per conductor SHD-GC 2001 to 5000 volts SHD-CGC 2001 to 5000 volts SHD-PCG 2001 to 5000 volts
6 93 1.56 1.62
4 122 1.68 1.73
3 140 1.78 1.82 1.94
2 159 1.87 1.91 2.03
1 184 1.95 1.98 2.12
1/0 211 2.08 2.10 2.26
2/0 243 2.20 2.20 2.40
3/0 279 2.36 2.36 2.58
4/0 321 2.50 2.50 2.76
250 355 2.69 2.69
300 398 2.81 2.81
350 435 2.95 2.95
500 536 3.31 3.31
* These ampacities are based on single isolated conductor in air, operated with open-circuited shield for a 90 °C conductor temperature and an ambient temperature of 40 °C.
** Tolerances for the outside diameter are + 8%/−5%.

Where this section sits in the code

Title 30—Mineral Resources
CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
SUBCHAPTER B—TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS
PART 18—ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES
Subpart D—Machines Assembled With Certified or Explosion-Proof Components, Field Modifications of Approved Machines, and Permits To Use Experimental Equipment

LIST OF TABLES

Table No. Title

1 Portable power cable ampacities—600 volts.

2 Portable cord ampacities—600 volts.

3 Portable power cable ampacities—601 to 5,000 volts.

4 Normal diameter of round cables with tolerances in inches—600 volts.

5 Nominal dimension of flat cables with tolerances in inches—600 volts.

6 Nominal diameter of heavy jacketed cords with tolerances in inches—600 volts.

7 Nominal diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts.

8 Fuse ratings or instantaneous settings of circuit breakers for short-circuit protection of portable cables.

9 Specifications for portable cables longer than 500 feet.

10 High voltage trailing cable ampacities and outside diameters.

Table 1—Portable Power Cable Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient)

Conductor size—AWG or MCM Single conductor 2-conductor, round or flat 3-conductor, round or flat 4-conductor 5-conductor 6-conductor

8 45 40 35 30 25 20

6 60 50 50 40 35 30

4 85 70 65 55 45 35

3 95 80 75 65 55 45

2 110 95 90 75 65 55

1 130 110 100 85 75 65

1/0 150 130 120 100 90 80

2/0 175 150 135 115 105 95

3/0 205 175 155 130 120 110

4/0 235 200 180 150 140 130

250 275 220 200 160

300 305 240 220 175

350 345 240 235 190

400 375 280 250 200

450 400 300 270 215

500 425 320 290 230

Table 2—Portable Cord Ampacities—600 Volts (Amperes Per Conductor Based on 60 °C. Copper Temperature—40 °C. Ambient)

Conductor size—AWG 1-3 conductor 4-6 conductor 7-9 conductor

14 15 12 8

12 20 16 11

10 25 20 14

Table 3—Portable Power Cable Ampacities—601 to 5,000 Volts (Amperes Per Conductor Based on 75 °C. Copper Temperature—40 °C. Ambient)

Conductor size—AWG or MCM 3-conductor types G-GC and SIIC-GC 2,000 volts 3-conductor type SHD-GC 2,001-5,000 volts

6 65 65

4 85 85

3 100 100

2 115 115

1 130 130

1/0 145 145

2/0 170 170

3/0 195 195

4/0 220 220

250 245 245

300 275 275

350 305 305

Table 4—Nominal Diameters of Round Cables With Tolerances in Inches—600 Volts

Conductor size—AWG or MCM Single conductor 2-conductor 3-conductor 4-conductor—Types W & G 5-conductor—Types W & G 6-conductor

Types W & G twisted Type PG, 2 power Type PCG, 3 power, ground Types W & G Type PG, 3 power, ground Type PCG, 3 power, 2 control, ground Type w Tolerance

8 0.44 0.81 0.84 0.94 0.91 0.93 1.03 0.99 1.07 1.18 ±0.03

6 .51 .93 .93 .98 1.01 1.03 1.18 1.10 1.21 1.31 ±.03

4 .57 1.08 1.08 1.10 1.17 1.20 1.29 1.27 1.40 1.52 ±.03

3 .63 1.17 1.17 1.20 1.24 1.27 1.31 1.34 1.48 1.61 ±.03

2 .66 1.27 1.27 1.29 1.34 1.34 1.39 1.48 1.61 1.75 ±.03

1 .74 1.44 1.44 1.44 1.51 1.52 1.52 1.68 1.88 2.05 ±.03

1/0 .77 1.52 1.52 1.52 1.65 1.68 1.68 1.79 1.96 2.13 ±.04

2/0 .82 1.65 1.65 1.65 1.75 1.79 1.79 1.93 2.13 2.32 ±.04

3/0 .87 1.77 1.77 1.77 1.89 1.93 1.93 2.07 2.26 2.49 ±.05

4/0 .93 1.92 1.92 1.92 2.04 2.13 2.13 2.26 2.46 2.71 ±.05

250 1.03 2.16 2.16 2.16 2.39 2.39 2.39 2.66 ±.06

300 1.09 2.32 2.56 2.84 ±.06

350 1.15 2.43 2.68 2.98 ±.06

400 1.20 2.57 2.82 3.14 ±.06

450 1.26 2.67 2.94 3.26 ±.06

500 1.31 2.76 3.03 3.40 ±.06

Table 5—Nominal Dimensions of Flat Cables With Tolerances in Inches—600 Volts

Conductor size—AWG 2-conductor 3-conductor—Type G

Type W Type G Major Minor

Major Minor Major Minor O.D. Tolerance O.D. Tolerance

O.D. Tolerance O.D. Tolerance O.D. Tolerance O.D. Tolerance

8 0.84 ±0.04 0.51 ±0.03

6 .93 ±.04 .56 ±.03 1.02 ±.04 0.56 ±.03 1.65 ±0.06 0.67 ±0.05

4 1.05 ±.04 .61 ±.03 1.15 ±.04 .61 ±.03 1.85 ±.06 .75 ±.05

3 1.14 ±.04 .68 ±.03 1.26 ±.04 .68 ±.03 1.99 ±.06 .77 ±.05

2 1.24 ±.04 .73 ±.03 1.35 ±.04 .73 ±.06 2.10 ±.06 .81 ±.05

1 1.40 ±.04 .81 ±.03 1.55 ±.04 .81 ±.03 2.43 ±.06 .97 ±.05

1/0 1.51 ±.04 .93 ±.03 1.67 ±.04 .93 ±.03

2/0 1.63 ±.04 .99 ±.03 1.85 ±.04 .99 ±.03

3/0 1.77 ±.04 1.03 ±.03 2.00 ±.04 1.03 ±.03

4/0 1.89 ±.04 1.10 ±.03 2.10 ±.04 1.10 ±.03

Table 6—Nominal Diameters of Heavy Jacketed Cords With Tolerances In Inches—600 Volts

Conductor size—AWG 2-conductor 3-conductor 4-conductor 5-conductor 6-conductor 7-conductor

Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance

14 0.64 ±0.02 0.67 ±0.02 0.71 ±0.02 0.78 ±0.03 0.83 ±0.03 0.89 ±0.03

12 .68 ±.02 .72 ±.03 .76 ±.03 .83 ±.03 .89 ±.03 .98 ±.03

10 .73 ±.03 .80 ±.03 .84 ±.03 .90 ±.03 1.00 ±.03 1.07 ±.03

Table 7—Nominal Diameters of Three-Conductor Portable Power Cables With Tolerances in Inches—601 to 5,000 Volts

Conductor size—AWG or MCM Type G-GC (nonshielded) 2,000 volts Type SHC-GC (shielded overall) 2,000 volts Type SHD-GC (individually shielded power conductors) 2,001-3,000 volts Type SHD-GC (individually shielded power conductors) 3,001-5,000 volts

Diameter Tolerance Diameter Tolerance Diameter Tolerance Diameter Tolerance

6 1.25 + 0.10, −0.06 1.39 + 0.11, −0.07 1.62 + 0.13, −0.08 1.78 + 0.14, −0.09

4 1.40 + .11, −.07 1.55 + .12, −.08 1.77 + .14, −.09 1.90 + .15, −.10

3 1.48 + .12, −.07 1.62 + .13, −.08 1.84 + .15, −.09 1.98 + .16, −.10

2 1.55 + .12, −.08 1.71 + .14, −.09 1.92 + .15, −.10 2.09 + .17, −.11

1 1.74 + .14, −.09 1.89 + .15, −.09 2.04 + .16, −.10 2.18 + .17, −.11

1/0 1.84 + .15, −.09 2.02 + .16, −.10 2.18 + .17, −.11 2.34 + .19, −.12

2/0 1.99 + .16, −.10 2.16 + .17, −.11 2.29 + .18, −.12 2.46 + .20, −.12

3/0 2.12 + .17, −.11 2.30 + .18, −.11 2.45 + .20, −.12 2.62 + .21, −.13

4/0 2.30 + .18, −.12 2.48 + .20, −.12 2.62 + .21, −.13 2.76 + .22, −.14

250 2.46 + .20, −.12 2.70 + .22, −.13

300 2.63 + .21, −.13 2.84 + .23, −.14

350 2.75 + .22, −.14 2.97 + .24, −.15

Table 8—Fuse Ratings or Instantaneous Setting of Circuit Breakers for Short-Circuit Protection of Portable Cables and Cords

Conductor size—AWG or MCM Ohms/1,000 ft. at 25 °C. Maximum allowable fuse rating (amperes) Maximum allowable circuit breaker instantaneous setting (amperes) 1

14 2.62 20 50

12 1.65 30 75

10 1.04 40 150

8 .654 80 200

6 .410 100 300

4 .259 200 500

3 .205 250 600

2 .162 300 800

1 .129 375 1,000

1/0 .102 500 1,250

2/0 .081 1,500

3/0 .064 2,000

4/0 .051 2,500

250 .043 2,500

300 .036 2,500

350 .031 2,500

400 .027 2,500

450 .024 2,500

500 .022 2,500

1 Higher circuit-breaker settings may be permitted for special applications when justified.

Table 9—Specifications for Portable Cables Longer Than 500 Feet 1

Conductor size—AWG or MCM Max. allowable length (feet) Normal ampacity at 60 °C. copper temperature (40 °C. ambient) Resistance at 60 °C. copper temperature (ohms)

6 550 50 0.512

4 600 70 .353

3 650 80 .302

2 700 95 .258

1 750 110 .220

1/0 800 130 .185

2/0 850 150 .157

3/0 900 175 .130

4/0 1,000 200 .116

250 1,000 220 .098

300 1,000 240 .082

350 1,000 260 .070

400 1,000 280 .061

450 1,000 300 .054

500 1,000 320 .050

1 Fuses shall not be used for short-circuit protection of these cables. Circuit breakers shall be used with the instantaneous trip settings not to exceed the values given in Table 8.

Table 10—High Voltage Trailing Cable Ampacities and Outside Diameters

Power conductor Ampacity * Outside diameter ** (inches)

Size AWG or kcmil Amperes per conductor SHD-GC 2001 to 5000 volts SHD-CGC 2001 to 5000 volts SHD-PCG 2001 to 5000 volts

6 93 1.56 1.62

4 122 1.68 1.73

3 140 1.78 1.82 1.94

2 159 1.87 1.91 2.03

1 184 1.95 1.98 2.12

1/0 211 2.08 2.10 2.26

2/0 243 2.20 2.20 2.40

3/0 279 2.36 2.36 2.58

4/0 321 2.50 2.50 2.76

250 355 2.69 2.69

300 398 2.81 2.81

350 435 2.95 2.95

500 536 3.31 3.31

* These ampacities are based on single isolated conductor in air, operated with open-circuited shield for a 90 °C conductor temperature and an ambient temperature of 40 °C.

** Tolerances for the outside diameter are + 8%/−5%.

Collected 2026-08-27T02:25:24Z. Source file · JSON

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