CONDUCTOR AND INSULATOR TABLES

Copper wire gage table

Soild copper wire table:

Size        Diameter         Cross-sectional area       Weight
AWG inches cir. mils sq. inches lb/1000 ft
================================================================
4/0 -------- 0.4600 ------- 211,600 ------ 0.1662 ------ 640.5
3/0 -------- 0.4096 ------- 167,800 ------ 0.1318 ------ 507.9
2/0 -------- 0.3648 ------- 133,100 ------ 0.1045 ------ 402.8
1/0 -------- 0.3249 ------- 105,500 ----- 0.08289 ------ 319.5
1 ---------- 0.2893 ------- 83,690 ------ 0.06573 ------ 253.5
2 ---------- 0.2576 ------- 66,370 ------ 0.05213 ------ 200.9
3 ---------- 0.2294 ------- 52,630 ------ 0.04134 ------ 159.3
4 ---------- 0.2043 ------- 41,740 ------ 0.03278 ------ 126.4
5 ---------- 0.1819 ------- 33,100 ------ 0.02600 ------ 100.2
6 ---------- 0.1620 ------- 26,250 ------ 0.02062 ------ 79.46
7 ---------- 0.1443 ------- 20,820 ------ 0.01635 ------ 63.02
8 ---------- 0.1285 ------- 16,510 ------ 0.01297 ------ 49.97
9 ---------- 0.1144 ------- 13,090 ------ 0.01028 ------ 39.63
10 --------- 0.1019 ------- 10,380 ------ 0.008155 ----- 31.43
11 --------- 0.09074 ------- 8,234 ------ 0.006467 ----- 24.92
12 --------- 0.08081 ------- 6,530 ------ 0.005129 ----- 19.77
13 --------- 0.07196 ------- 5,178 ------ 0.004067 ----- 15.68
14 --------- 0.06408 ------- 4,107 ------ 0.003225 ----- 12.43
15 --------- 0.05707 ------- 3,257 ------ 0.002558 ----- 9.858
16 --------- 0.05082 ------- 2,583 ------ 0.002028 ----- 7.818
17 --------- 0.04526 ------- 2,048 ------ 0.001609 ----- 6.200
18 --------- 0.04030 ------- 1,624 ------ 0.001276 ----- 4.917
19 --------- 0.03589 ------- 1,288 ------ 0.001012 ----- 3.899
20 --------- 0.03196 ------- 1,022 ----- 0.0008023 ----- 3.092
21 --------- 0.02846 ------- 810.1 ----- 0.0006363 ----- 2.452
22 --------- 0.02535 ------- 642.5 ----- 0.0005046 ----- 1.945
23 --------- 0.02257 ------- 509.5 ----- 0.0004001 ----- 1.542
24 --------- 0.02010 ------- 404.0 ----- 0.0003173 ----- 1.233
25 --------- 0.01790 ------- 320.4 ----- 0.0002517 ----- 0.9699
26 --------- 0.01594 ------- 254.1 ----- 0.0001996 ----- 0.7692
27 --------- 0.01420 ------- 201.5 ----- 0.0001583 ----- 0.6100
28 --------- 0.01264 ------- 159.8 ----- 0.0001255 ----- 0.4837
29 --------- 0.01126 ------- 126.7 ----- 0.00009954 ---- 0.3836
30 --------- 0.01003 ------- 100.5 ----- 0.00007894 ---- 0.3042
31 -------- 0.008928 ------- 79.70 ----- 0.00006260 ---- 0.2413
32 -------- 0.007950 ------- 63.21 ----- 0.00004964 ---- 0.1913
33 -------- 0.007080 ------- 50.13 ----- 0.00003937 ---- 0.1517
34 -------- 0.006305 ------- 39.75 ----- 0.00003122 ---- 0.1203
35 -------- 0.005615 ------- 31.52 ----- 0.00002476 — 0.09542
36 -------- 0.005000 ------- 25.00 ----- 0.00001963 — 0.07567
37 -------- 0.004453 ------- 19.83 ----- 0.00001557 — 0.06001
38 -------- 0.003965 ------- 15.72 ----- 0.00001235 — 0.04759
39 -------- 0.003531 ------- 12.47 ---- 0.000009793 — 0.03774
40 -------- 0.003145 ------- 9.888 ---- 0.000007766 — 0.02993
41 -------- 0.002800 ------- 7.842 ---- 0.000006159 — 0.02374
42 -------- 0.002494 ------- 6.219 ---- 0.000004884 — 0.01882
43 -------- 0.002221 ------- 4.932 ---- 0.000003873 — 0.01493
44 -------- 0.001978 ------- 3.911 ---- 0.000003072 — 0.01184

Copper wire ampacity table

Ampacities of copper wire, in free air at 30o C:

========================================================
| INSULATION TYPE: |
| RUW, T THW, THWN FEP, FEPB |
| TW RUH THHN, XHHW |
========================================================
Size Current Rating Current Rating Current Rating
AWG @ 60 degrees C @ 75 degrees C @ 90 degrees C
========================================================
20 -------- *9 ----------------------------- *12.5
18 -------- *13 ------------------------------ 18
16 -------- *18 ------------------------------ 24
14 --------- 25 ------------- 30 ------------- 35
12 --------- 30 ------------- 35 ------------- 40
10 --------- 40 ------------- 50 ------------- 55
8 ---------- 60 ------------- 70 ------------- 80
6 ---------- 80 ------------- 95 ------------ 105
4 --------- 105 ------------ 125 ------------ 140
2 --------- 140 ------------ 170 ------------ 190
1 --------- 165 ------------ 195 ------------ 220
1/0 ------- 195 ------------ 230 ------------ 260
2/0 ------- 225 ------------ 265 ------------ 300
3/0 ------- 260 ------------ 310 ------------ 350
4/0 ------- 300 ------------ 360 ------------ 405


* = estimated values; normally, wire gages this small are not manufactured with these insulation types.

Coefficients of specific resistance

Specific resistance at 20o C:

Material      Element/Alloy        (ohm-cmil/ft)        (ohm-cm·10-6)
====================================================================
Nichrome ------- Alloy ---------------- 675 ------------- 112.2
Nichrome V ----- Alloy ---------------- 650 ------------- 108.1
Manganin ------- Alloy ---------------- 290 ------------- 48.21
Constantan ----- Alloy ---------------- 272.97 ---------- 45.38
Steel* --------- Alloy ---------------- 100 ------------- 16.62
Platinum ------ Element --------------- 63.16 ----------- 10.5
Iron ---------- Element --------------- 57.81 ----------- 9.61
Nickel -------- Element --------------- 41.69 ----------- 6.93
Zinc ---------- Element --------------- 35.49 ----------- 5.90
Molybdenum ---- Element --------------- 32.12 ----------- 5.34
Tungsten ------ Element --------------- 31.76 ----------- 5.28
Aluminum ------ Element --------------- 15.94 ----------- 2.650
Gold ---------- Element --------------- 13.32 ----------- 2.214
Copper -------- Element --------------- 10.09 ----------- 1.678
Silver -------- Element --------------- 9.546 ----------- 1.587


* = Steel alloy at 99.5 percent iron, 0.5 percent carbon.

Temperature coefficients of resistance

Temperature coefficient (α) per degree C:

Material     Element/Alloy         Temp. coefficient
=====================================================
Nickel -------- Element --------------- 0.005866
Iron ---------- Element --------------- 0.005671
Molybdenum ---- Element --------------- 0.004579
Tungsten ------ Element --------------- 0.004403
Aluminum ------ Element --------------- 0.004308
Copper -------- Element --------------- 0.004041
Silver -------- Element --------------- 0.003819
Platinum ------ Element --------------- 0.003729
Gold ---------- Element --------------- 0.003715
Zinc ---------- Element --------------- 0.003847
Steel* --------- Alloy ---------------- 0.003
Nichrome ------- Alloy ---------------- 0.00017
Nichrome V ----- Alloy ---------------- 0.00013
Manganin ------- Alloy ------------ +/- 0.000015
Constantan ----- Alloy --------------- -0.000074


* = Steel alloy at 99.5 percent iron, 0.5 percent carbon

Critical temperatures for superconductors

Critical temperatures given in Kelvins

Material     Element/Alloy      Critical temperature(K)
=======================================================
Aluminum -------- Element --------------- 1.20
Cadmium --------- Element --------------- 0.56
Lead ------------ Element --------------- 7.2
Mercury --------- Element --------------- 4.16
Niobium --------- Element --------------- 8.70
Thorium --------- Element --------------- 1.37
Tin ------------- Element --------------- 3.72
Titanium -------- Element --------------- 0.39
Uranium --------- ELement --------------- 1.0
Zinc ------------ Element --------------- 0.91
Niobium/Tin ------ Alloy ---------------- 18.1
Cupric sulphide - Compound -------------- 1.6










Critical temperatures, high temperature superconuctors in Kelvins
Material Critical temperature(K)
=======================================================
HgBa2Ca2Cu3O8+d ---------------- 150 (23.5 GPa pressure)
HgBa2Ca2Cu3O8+d ---------------- 133
Tl2Ba2Ca2Cu3O10 ---------------- 125
YBa2Cu3O7 ---------------------- 90
La1.85Sr0.15CuO4 ---------------- 40
Cs3C60 ------------------------- 40 (15 Kbar pressure)
Ba0.6K0.4BiO3 ------------------- 30
Nd1.85Ce0.15CuO4 ---------------- 22
K3C60 -------------------------- 19
PbMo6S8 ------------------------ 12.6


Note: all critical temperatures given at zero magnetic field strength.

Dielectric strengths for insulators

Dielectric strength in kilovolts per inch (kV/in):

Material*         Dielectric strength
=========================================
Vacuum --------------------- 20
Air ------------------------ 20 to 75
Porcelain ------------------ 40 to 200
Paraffin Wax --------------- 200 to 300
Transformer Oil ------------ 400
Bakelite ------------------- 300 to 550
Rubber --------------------- 450 to 700
Shellac -------------------- 900
Paper ---------------------- 1250
Teflon --------------------- 1500
Glass ---------------------- 2000 to 3000
Mica ----------------------- 5000


* = Materials listed are specially prepared for electrical use

Data

Tables of specific resistance and temperature coefficient of resistance for elemental materials (not alloys) were derived from figures found in the 78th edition of the CRC Handbook of Chemistry and Physics. Superconductivity data from Collier's Encyclopedia (volume 21, 1968, page 640).