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

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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

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Temperature coefficients of resistance

Temperature coefficient ( ) 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

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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

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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   @ 60degrees C   @ 75degrees C   @ 90degrees 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

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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

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