Technical Data

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Property	Copper	Aluminum
Volume Conductivity @ 20°C (IACS)	100.0%	61.8%
Volume Resistivity @ 20°C (ohm-cir mil per foot)	10.371	16.782
Temperature Coefficient of Resistance @ 20°C	0.00393	0.00410
Coefficient of Linear Expansion (per °C)	0.000017	0.000023
Density @ 20°C (gm/cubic cm)	8.89	2.703

Temperature		Resistance Correction Factor
°C	°F	Copper	Aluminum
15.0	59.0	0.9804
16.0	60.8	0.9842
17.0	62.6	0.9882
18.0	64.4	0.9922
19.0	66.2	0.9961
20.0	68.0	1.0000	1.0000
20.5	68.9	1.0020	1.0021
21.0	69.8	1.0039	1.0041
21.5	70.7	1.0059	1.0062
22.0	71.6	1.0079	1.0082
22.5	72.5	1.0098	1.0103
23.0	73.4	1.0118	1.0123
23.5	74.3	1.0138	1.0144
24.0	75.2	1.0157	1.0164
24.5	76.1	1.0177	1.0185
25.0	77.0	1.0197	1.0205
25.5	77.9	1.0216	1.0226
26.0	78.8	1.0236	1.0246
26.5	79.7	1.0255	1.0267
27.0	80.6	1.0275	1.0287
27.5	81.5	1.0295	1.0308
28.0	82.4	1.0314	1.0328
28.5	83.3	1.0334	1.0349
29.0	84.2	1.0354	1.0369
29.5	85.1	1.0373	1.0390
30.0	86.0	1.0393	1.0410
30.5	86.9	1.0413	1.0431
31.0	87.8	1.0433
32.0	89.6	1.0471
33.0	91.4	1.0511
34.0	93.2	1.0551
35.0	95.0	1.0590
36.0	96.8	1.0630
37.0	98.6	1.0668
38.0	100.4	1.0709
39.0	102.2	1.0747
40.0	104.0	1.0786
To convert resistance to 20°C (68°F), divide resistance by the correction factor for the corresponding temperature and metal indicated in the above table.To find ohms/foot, divide Volume Resistivity by area in circular mils.

°C	Temperature	°F
-17.8°C	0	32°F
-12.2°C	10	50°F
-6.7°C	20	68°F
-1.1°C	30	86°F
4.4°C	40	104°F
10.0°C	50	122°F
15.6°C	60	140°F
21.1°C	70	158°F
26.7°C	80	176°F
32.2°C	90	194°F
37.8°C	100	212°F
43.3°C	110	230°F
48.9°C	120	248°F
54.4°C	130	266°F
60.0°C	140	284°F
65.6°C	150	302°F
71.1°C	160	320°F
76.7°C	170	338°F
82.2°C	180	356°F
87.8°C	190	374°F
93.3°C	200	392°F
98.9°C	210	410°F
104.4°C	220	428°F
110.0°C	230	446°F
115.6°C	240	464°F
121.1°C	250	482°F
126.7°C	260	500°F
132.2°C	270	518°F
137.8°C	280	536°F
143.3°C	290	554°F
148.9°C	300	572°F
154.4°C	310	590°F
160.0°C	320	608°F
165.6°C	330	626°F
171.1°C	340	644°F
176.7°C	350	662°F
182.2°C	360	680°F
187.8°C	370	698°F
193.3°C	380	716°F
198.9°C	390	734°F
204.4°C	400	752°F
210.0°C	410	770°F
215.6°C	420	788°F
221.1°C	430	806°F
226.7°C	440	824°F
232.2°C	450	842°F
237.8°C	460	860°F
243.3°C	470	878°F
248.9°C	480	896°F
254.4°C	490	914°F
260.0°C	500	932°F
265.6°C	510	950°F
271.1°C	520	968°F
The center column of numbers refer to the temperature (in degrees C or F) which is to be converted to the other scale.Example 1: 70°F to be converted to °C. Find 70 in the center column and read 21.1°C to the left.Example 2: 70°C to be converted to °F. Find 70 in the center column and read 158°F to the right.

Unit Conversion

Conversion – AWG to mm
AWG	Nom	Exact	AWG	Nom	Exact	AWG	Nom	Exact
Size	In	mm	Size	In	mm	Size	In	mm
12.0	0.0808	2.05	21.5	0.0269	0.68	31	0.0089	0.23
12.5	0.0764	1.94	22.0	0.0253	0.64	32	0.0080	0.20
13.0	0.0720	1.83	22.5	0.0240	0.61	33	0.0071	0.18
13.5	0.0681	1.73	23.0	0.0226	0.57	34	0.0063	0.16
14.0	0.0641	1.63	23.5	0.0214	0.54	35	0.0056	0.14
14.5	0.0606	1.54	24.0	0.0201	0.51	36	0.0050	0.13
15.0	0.0571	1.45	24.5	0.0190	0.48	37	0.0045	0.11
15.5	0.0540	1.37	25.0	0.0179	0.45	38	0.0040	0.10
16.0	0.0508	1.29	25.5	0.0169	0.43	39	0.0035	0.09
16.5	0.0481	1.22	26.0	0.0159	0.40	40	0.0031	0.08
17.0	0.0453	1.15	26.5	0.0150	0.38	41	0.0028	0.07
17.5	0.0428	1.09	27.0	0.0142	0.36	42	0.0025	0.06
18.0	0.0403	1.02	27.5	0.0134	0.34	43	0.0022	0.06
18.5	0.0381	0.97	28.0	0.0126	0.32	44	0.0020	0.05
19.0	0.0359	0.91	28.5	0.0120	0.30	45	0.0018	0.05
19.5	0.0340	0.86	29.0	0.0113	0.29	46	0.0016	0.04
20.0	0.0320	0.81	29.5	0.0107	0.27	47	0.0014	0.04
20.5	0.0303	0.77	30.0	0.0100	0.25
21.0	0.0285	0.72	30.5	0.0095	0.24

Conversion – mm to AWG
mm	NOM	Exact	mm	Nom	Exact	mm	Nom	Exact
Size	In	AWG	Size	In	AWG	Size	In	AWG
2.00	0.0787	12.22	0.55	0.0217	23.36	0.22	0.0087	31.26
1.90	0.0748	12.67	0.50	0.0197	24.18	0.21	0.0083	31.66
1.80	0.0709	13.13	0.48	0.0189	24.53	0.20	0.0079	32.08
1.70	0.0669	13.63	0.46	0.0181	24.90	0.19	0.0075	32.53
1.60	0.0630	14.15	0.44	0.0173	25.28	0.18	0.0071	32.99
1.50	0.0591	14.70	0.42	0.0165	25.68	0.17	0.0067	33.48
1.40	0.0051	15.30	0.40	0.0157	26.10	0.16	0.0063	34.01
1.30	0.0512	15.94	0.38	0.0150	26.55	0.15	0.0059	34.56
1.20	0.0472	16.63	0.36	0.0142	27.01	0.14	0.0055	35.16
1.10	0.0433	17.78	0.34	0.0134	27.51	0.13	0.0051	35.80
1.00	0.0394	18.20	0.32	0.0126	28.03	0.12	0.0047	36.49
0.95	0.0374	18.64	0.30	0.0118	28.59	0.11	0.0043	37.24
0.90	0.0354	19.11	0.29	0.0114	28.88	0.10	0.0039	38.06
0.85	0.0335	19.60	0.28	0.0110	29.18	0.09	0.0035	38.97
0.80	0.0315	20.13	0.27	0.0106	29.49	0.08	0.0031	39.99
0.75	0.0295	20.68	0.26	0.0102	29.82	0.07	0.0028	41.14
0.70	0.0276	21.28	0.25	0.0098	30.16	0.06	0.0024	42.47
0.65	0.0256	21.92	0.24	0.0094	30.51	0.05	0.0020	44.04
0.60	0.0236	22.61	0.23	0.0091	30.88	0.04	0.0016	45.96