NEC Chapter 9 Table 8 — Conductor Properties

Size(AWGor kcmil)	Area	Diameter	Diameter	Area	Uncoated	Coated	Aluminum
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

Size(AWGor kcmil)

Area

Diameter

Area

Uncoated

Coated

Aluminum

Size(AWGor kcmil)

mm2

Circularmils

Quantity

in.

mm2

in.2

ohm/km

ohm/kFT

ohm/km

ohm/kFT

ohm/km

ohm/kFT

0.823

1620

—

1.02

0.040

0.823

0.001

25.5

7.77

26.5

8.08

42.0

12.8

0.823

1620

0.39

0.015

1.16

0.046

1.06

0.002

26.1

7.95

27.7

8.45

42.8

13.1

1.31

2580

—

1.29

0.051

1.31

0.002

16.0

4.89

16.7

5.08

26.4

8.05

1.31

2580

0.49

0.019

1.46

0.058

1.68

0.003

16.4

4.99

17.3

5.29

26.9

8.21

2.08

4110

—

1.63

0.064

2.08

0.003

10.1

3.07

10.4

3.19

16.6

5.06

2.08

4110

0.62

0.024

1.85

0.073

2.68

0.004

10.3

3.14

10.7

3.26

16.9

5.17

3.31

6530

—

2.05

0.081

3.31

0.005

6.34

1.93

6.57

2.01

10.45

3.18

3.31

6530

0.78

0.030

2.32

0.092

4.25

0.006

6.50

1.98

6.73

2.05

10.69

3.25

5.261

10380

—

2.588

0.102

5.26

0.008

3.984

1.21

4.148

1.26

6.561

2.00

5.261

10380

0.98

0.038

2.95

0.116

6.76

0.011

4.070

1.24

4.226

1.29

6.679

2.04

8.367

16510

—

3.264

0.128

8.37

0.013

2.506

0.764

2.579

0.786

4.125

1.26

8.367

16510

1.23

0.049

3.71

0.146

10.76

0.017

2.551

0.778

2.653

0.809

4.204

1.28

13.30

26240

1.56

0.061

4.67

0.184

17.09

0.027

1.608

0.491

1.671

0.510

2.652

0.808

21.15

41740

1.96

0.077

5.89

0.232

27.19

0.042

1.010

0.308

1.053

0.321

1.666

0.508

26.67

52620

2.20

0.087

6.60

0.260

34.28

0.053

0.802

0.245

0.833

0.254

1.320

0.403

33.62

66360

2.47

0.097

7.42

0.292

43.23

0.067

0.634

0.194

0.661

0.201

1.045

0.319

42.41

83690

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

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

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

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

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

—

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

Race your codebook — 3 lookups on this table

An elevator's operating control panel uses a Class 2 power-limited control circuit. Which section specifies how this circuit must be protected against overcurrent?

A 620.61(D)
B 620.61(A)
C 620.61(B)(3)
D 620.61(C)

Show answer & explanation

Correct: B — 620.61(A)

620.61(A) governs overcurrent protection of operating devices and control/signaling circuits, pointing to 724.43/724.45 and Chapter 9 Table 11 notes for Class 2 circuits. 620.61(B)(3) instead covers overload protection for motors, not control circuit overcurrent protection.

A designer is running Class 2 power-limited cables inside a nonmetallic snap-together cable routing assembly above a suspended ceiling in a commercial building. Which section specifies the selection, listing, and installation requirements for the cables run in this cable routing assembly?

A 722.3(C)
B 722.3(K)
C 722.3(L)
D 722.3(E)

Show answer & explanation

Correct: B — 722.3(K)

722.3(K) governs cables installed in cable routing assemblies, pointing to Table 800.154(c) for selection and 800.113 for installation. 722.3(L) covers a different raceway type (communications raceways referencing ENT rules), and 722.3(E)/(C) address cable trays and air-handling spaces, not routing assemblies.

A contractor plans to install Class 3 power-limited cables inside a communications raceway that resembles ENT tubing, routed through a commercial ceiling. Which section directs the selection, listing, and installation rules for cables run in this type of raceway?

A 722.3(L)
B 722.3(F)
C 722.3(K)
D 722.3(I)

Show answer & explanation

Correct: A — 722.3(L)

722.3(L) covers communications raceways, requiring selection per Table 800.154(b) and installation per 800.113 and the ENT rules in 362.24 through 362.56. 722.3(K) instead applies to cable routing assemblies, and 722.3(F)/(I) address instrumentation tray cable and installation with other systems, neither of which fits a communications raceway.

Chapter 9, Table 8 — conductor properties

Race your codebook — 3 lookups on this table

Every table. Timed lookups. Spaced repetition.

Chapter 9, Table 8 — conductor properties

Race your codebook — 3 lookups on this table

Keep going

Every table. Timed lookups. Spaced repetition.