Table 3 Table 310-16

Allowable Ampacities of Insulated Conductors Rated 0-2000 Volts, 60° to 90°C (140° to 194°F) 1

Not More than Three Conductors in Raceway or Cable or Earth (Directly Buried), based on Ambient Temperature of 30° (86°F)

Size

 

 

Temperature Rating of Conductor. See Table 310-13.

 

Size

 

 

 

 

 

 

 

 

 

 

 

60°C

75°C

90°C

60°C

75°C

90°C

 

 

 

(140°F)

(167°F)

(194°F)

(140°F)

(167°F)

(194°F)

 

 

 

 

 

 

 

 

 

 

 

 

Types

Types

Types

Types

Types

Types

 

 

 

TW†

FEPW+,

TBS, SA,

TW†

RH†, RHW†,

TBS,

 

 

 

UF†

RH,RHW†,

SIS,FEP†,

UF†

THHW†,

SA,SIS,

 

AWG

 

THHW†,

FEPB†,MI,

 

THW†,

THHN†,

AWG

 

THW†,

RHH†, RHW-2

 

THWN†,

THHW†,

kcmil

 

 

kcmil

 

THWN†,

THHN†,THHW†,

 

XHHW†,

THW-2, THWN-2,

 

 

 

XHHW†,

THW-2,THWN-2,

 

USE†

RHH†, RHW-2,

 

 

 

 

USE†, ZW†

USE-2, XHH,

 

 

USE-2,

 

 

 

 

 

XHHW†

 

 

XHH, XHHW†,

 

 

 

 

 

XHHW-2,ZW-2

 

 

XHHW-2, ZW-2

 

 

 

 

 

 

 

 

 

 

 

 

Copper

 

Aluminum or Copper-Clad Aluminum

 

 

 

 

 

 

 

 

 

 

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 shown

Ambient

Temp °C

 

 

above by the appropriate factor shown below.

 

Temp °F

 

 

 

 

 

 

 

 

 

21-25

1.08

1.05

 

1.04

1.08

1.05

1.04

70-77

26-30

1.00

1.00

 

1.00

1.00

1.00

1.00

78-86

31-35

.91

.94

 

.96

.91

.94

.96

87-95

36-40

.82

.88

 

.91

.82

.88

.91

96-104

41-45

.71

.82

 

.87

.71

.82

.87

105-113

46-50

.58

.75

 

.82

.58

.75

.82

114-122

51-55

.41

.67

 

.76

.41

.67

.76

123-131

56-60

.......

.58

 

.71

.......

.58

.71

132-140

61-70

.......

.33

 

.58

.......

.33

.58

141-158

71-80

.......

.......

 

.41

.......

.......

.41

159-176

 

 

 

 

 

 

 

 

 

† Unless otherwise specifically permitted elsewhere in this Code, the overcurrent protection for conductor types marked with an obelisk (†) shall not exceed 15 amperes for No. 14, 20 amperes for No. 12, and 30 amperes for No. 10 copper; or 15 amperes for No. 12 and 25 amperes for No. 10 aluminum and copper-clad aluminum after any correction factors for ambient temperature and number of conductors have been applied.

1 Reprinted with permission from NFPA 70-1993, the National Electrical Code®, Copyright 1996, National Fire Protection Association, Quincy, MA 02269. This reprinted material is not the complete and official position of the National Fire Protection Association, on the referenced subject which is represented only by the standard in its entirety.

20 Wiring Inspection

Page 26
Image 26
Liebert Series 600 manual Copper Aluminum or Copper-Clad Aluminum