From: [email protected]
Date: Mon Nov 13 2000 - 15:09:36 PST
Doug,
Question #1. Despite some 16 months of searching for information on the
current-carrying
capacity (ampacity) of printed circuit boards, I know of no single source that
gives the
resistivity and temperature coefficient of resistivity for copper used on
printed circuit
boards. But between:
* IPC-D-317A Design Guidelines for Electronic Packaging Utilizing High-Speed
Techniques
(must be purchased from the IPC),
* IPC-MF-150F Metal Foil for Printed Wiring Applications (must be purchased
from the IPC), and
* MIL-S-13949H Amendment 1 Military Specification Sheet, Printed Wiring Board
General
Specification for, and its slash sheets (can be downloaded from
http://www.dodssp.daps.mil/ )
we can come up with:
MAXIMUM RESISTIVITIES FOR COPPER
copper thickness maximum resistivity
---------------------- --------------------
E (1/8 ounce/ft^2) 0.181 ohm-gram/m^2 electrodeposited
Q (1/4 ounce/ft^2) 0.171 ohm-gram/m^2 electrodeposited
T (3/8 ounce/ft^2) 0.170 ohm-gram/m^2 electrodeposited
H (1/2 ounce/ft^2) 0.166 ohm-gram/m^2 electrodeposited
M (3/4 ounce/ft^2) 0.164 ohm-gram/m^2 electrodeposited
1 ounce and greater 0.162 ohm-gram/m^2 electrodeposited
type 5 0.158 ohm-gram/m^2 rolled wrought
type 6 0.153 to 0.157 ohm-gram/m^2 light cold rolled wrought
type 7 0.152 ohm-gram/m^2 annealed wrought
type 8 0.158 ohm-gram/m^2 as rolled wrought
http://www.tridentalloys.com/impalloy/tablcond.htm and various other sources
say that the
change in a metal's resistance as a function of temperature is
rho(t) = rho20 * (1 + a * (t - 20))
where:
* rho(t) is the resistivity at t degrees C.
* rho20 is the resistivity at 20 degrees C = 1.72 microhms-cm for copper.
* a is the temperature coefficient of resistance = 0.00393 for copper "around"
20C.
#2. The basic idea is to measure the resistance of the copper at 20C (R), and
again after it has
stabilized at some desired ambient temperature (R1). Then we heat up the
copper, by forcing a
certain current through it perhaps, then quickly measure the resistance again
before it has time
to cool off (R2). Since we haven't changed the dimensions (length, width,
thickness) of the copper,
the resistance is proportional to rho(t). So the "average" temperature rise of
the copper between
our measuring points is:
delta-t = (R2 - R1) / (R * 0.00393)
Because we are talking about only a 0.4% increase in resistance per degree C, we
will
probably need to use Kelvin (four-point) resistance measurements:
+------------------- current source --------------------+
! !
! +----- voltmeter -------+ !
! ! ! !
V V V V
---------o---------------o-----------------------o---------------o------
! measures !
!<-- this resistance -->!
We may also want to calibrate our test setup by putting it in a calibrated oven
(with a lab
thermometer, perhaps) to measure the resistance at various known temperatures,
to give us a
calibration curve that compensates for thermoelectric effects and other noise
factors in our
test setup. Widening the traces for our probe points, the mass of solder used,
and heat-sinking
by the voltage probes all distort the temperature distribution from that of the
trace by itself.
But their effects are *probably* of the same magnitude as heat-sinking by nearby
conductors/
insulators on the circuit board.
#3. Can't really help you here, but I have read about a bunch of wire and metal
sheet gauges
going back to the 1700's and 1800's. See
http://asuwlink.uwyo.edu/~metal/gage.html
http://www.lucent.com/networks/ewc/catalog/c04e.html#top talks about how
American Wire Gauge
(AWG) was derived from the Brown & Sharp (B&S) Gauge, which was designed by J.
R. Brown in 1857.
About the only characteristic that these gauges share is that they are
monotonic-- that a higher
gauge number means a thinner wire or sheet. Since you can shrink a wire/thin a
sheet only so much
in one pass through a die/set of rolls without excessive breakage, the gauge
number seems to
indicate how many drawing/rolling operations were used in making the wire or
sheet.
One of the handbooks in my collection at home (16 bookcases of electronics
books) has a table
giving nominal, minimum, and maximum diameters of the various AWG gauges of
wire. I remember
plotting these on semi-log paper, to try to find an easy equation to relate
gauge number to
diameter for Appendix D of my book (Electronic System Design: Interference and
Noise Control
Techniques, Prentice-Hall, 1987). There were some strange kinks in the curves,
but the
minimum diameter of AWG gauge N was always smaller than the maximum diameter of
AWG gauge N+1.
So whatever size of wire you happened to draw, you could sell it as *some* size
of wire. (Just
like the choices of nominal values for resistors).
The formulas that I came up with were
D = 0.00825 * (0.89054)^N meters for solid wires of AWG gauge N,
with a diameter tolerance of +0.5%/-1.0% or +/-2.54um, whichever was greater.
D = 0.00971 * (0.89054)^N meters for stranded wires of AWG gauge N,
with a diameter tolerance of +/-10%.
Here is a table that I put together summer 1999, with the nominal diameters of
solid and various
stranded constructions of copper wire:
NOMINAL DIAMETER AND RESISTANCE OF ROUND WIRES AT 20C
0% IACS 30% IACS
Nominal Circular Bare Cu Tinned Cu Ag-clad Cu
Ni-clad Cu Bare Al Cu-clad Al Fe Copperweld Copperweld
AWG Stranding Diameter Mil Area mOhms/foot mOhms/foot mOhms/foot
mOhms/foot mOhms/foot mOhms/foot mOhms/foot mOhms/foot mOhms/foot AWG
Stranding
--- ----------- -------- -------- ---------- ---------- ---------- ----------
---------- ---------- ---------- ---------- ---------- --- -----------
60 solid 0.0003" 0.1 108400
0 solid
59 solid 0.0003" 0.1 85930
9 solid
58 solid 0.0004" 0.2 68010
8 solid
57 solid 0.0004" 0.2 54060
7 solid
56 solid 0.0005" 0.2 43190
6 solid
55 solid 0.0006" 0.3 34280
5 solid
54 solid 0.0006" 0.4 26980
4 solid
53 solid 0.0007" 0.5 21170
3 solid
52 solid 0.0008" 0.6 17050
2 solid
51 solid 0.0009" 0.8 13390
1 solid
50 solid 0.0010" 1.0 10660
0 solid
49 solid 0.0011" 1.2 8454
9 solid
48 solid 0.0012" 1.4 6704
8 solid
47 solid 0.0014" 2.0 5291
7 solid
46 solid 0.0016" 2.7 4207
6 solid
45 solid 0.0018" 3.2 3348
5 solid
44 solid 0.0020" 4.0 2700
4182
44 solid
43 solid 0.0022" 4.8 2230
3456
43 solid
42 solid 0.0025" 6.3 1730
2676
42 solid
41 solid 0.0028" 7.8 1380
2134
41 solid
40 solid 0.0031" 9.6 1120 1126
1720 2680
3570 40 solid
39 solid 0.0035" 12.2 880
1360
2120 2830 39 solid
38 solid 0.0040" 16.0 674 708
1080 1680
2240 38 solid
37 solid 0.0045" 20.2 533
858
1330 1780 37 solid
36 solid 0.0050" 25.0 431 445
681 1060
1410 36 solid
36 7/44 0.006" 28.0 371 371
6 7/44
35 solid 0.0056" 31.4 344
540
839 1120 35 solid
34 solid 0.0063" 39.7 272 280
428 665
887 34 solid
34 7/42 0.0075" 43.8 237 237
4 7/42
33 solid 0.0071" 50.4 214 222
339 528
703 33 solid
32 solid 0.0080" 64.0 169 176 168
269 419 558
32 solid
32 7/40 0.009" 75 164 177 169 182
32 7/40
32 7/40 C 0.009" 81 177 169 182
32 7/40 C
32 19/44 0.009" 76.0 136 136
2 19/44
31 solid 0.0089" 79.2 136
213
332 442 31 solid
30 solid 0.010" 100 108 110 107
170 263 351
30 solid
30 7/38 C 0.012" 110 97.9 108 100 110
30 7/38 C
30 19/42 0.012" 119 87.3 87.3
0 19/42
29 solid 0.011" 128 84.5 87.8
133 209
278 29 solid
28 solid 0.013" 159 67.9 68.9 67.0
107 166 221 28
solid
28 7/36 C 0.015" 175 61.4 68.2 63.6
67.6 28 7/36 C
28 19/40 0.016" 182 56.7 67.7 62.9
28
19/40
27 solid 0.014" 202 53.5 55.6
84.3 131
175 27 solid
27 7/35 B 0.018" 220 51.5 53.8
7 7/35 B
27 7/35 C 0.018" 220 51.5 53.8
7 7/35 C
27 65/44 B 0.018" 260 42.0
7 65/44 B
26 solid 0.016" 253 42.7 43.3 41.8
67.3 104 139 26
solid
26 7/34 C 0.019" 276 38.6 40.9 40.9
26
7/34 C
26 10/36 SB 0.021" 250 43.0 41.5
6 10/36 SB
26 19/38 B 0.021" 304 34.1 40.1 37.3
41.0 26 19/38
B
26 19/38 C 0.021" 304 34.1 40.1 37.3
41.0 26 19/38
C
26 19/38 U 0.019" 304 36.0 40.1 37.3
41.0 26 19/38
U
25 solid 0.018" 320 33.7
53.1
82.6 110 25 solid
24 solid 0.020" 404 26.7 27.3 26.8
42.1 65.5 87.3 24
solid
24 7/32 B 0.024" 448 23.1 25.1 24.8
24
7/32 B
24 7/32 C 0.024" 442 24.3 25.1 24.8
24
7/32 C
24 10/34 SB 0.024" 398 27.0 26.1
4 10/34 SB
24 16/36 SB 0.024" 400 26.9 28.3
4 16/36 SB
24 19/36 C 0.025" 475 21.9 25.4 23.6
25.1 24 19/36
C
24 19/36 SB 0.024" 475 22.6 25.4 23.6
25.1 24 19/36
SB
24 41/40 0.025" 394 25.6 25.6
4 41/40
23 solid 0.023" 511 21.1
33.3
51.9 69.2 23 solid
22 solid 0.025" 640 16.9 16.8 17.1
26.6 41.2 54.9 22
solid
22 7/30 B 0.031" 700 14.8 16.2 15.2
22
7/30 B
22 7/30 C 0.030" 704 15.1 16.2 15.2
22
7/30 C
22 16/34 SB 0.032" 636 16.8 17.8
2 16/34 SB
22 19/34 E 0.032" 754 13.8 15.9 14.8
15.7 22 19/34
E
22 19/34 SB 0.030" 754 14.2 15.9 14.8
15.7 22 19/34
SB
22 26/36 0.033" 650 15.9 15.9
2 26/36
21 solid 0.029" 812 13.3
20.9
32.7 43.5 21 solid
20 solid 0.032" 1020 10.5 10.6 10.5
16.6 25.9 34.5 20
solid
20 7/.0121 C 0.036" 1025 10.3 10.9
0 7/.0121 C
20 7/28 B 0.038" 1111 9.33 10.1 9.46
20
7/28 B
20 7/28 C 0.038" 1119 9.63 10.1 9.46
20
7/28 C
20 10/30 SB 0.038" 1005 10.7 11.8
0 10/30 SB
20 19/.0071 E 0.036" 957 12.6
0 19/.0071 E
20 19/32 B 0.040" 1216 8.53 9.76 9.09
9.67 20 19/32 B
20 19/32 C 0.040" 1216 8.53 9.76 9.09
9.67 20 19/32 C
20 19/32 E 0.040" 1216 8.53 9.76 9.09
9.67 20 19/32 E
20 19/32 U 0.038" 1201 8.90 9.76 9.09
9.67 20 19/32 U
20 26/34 SB 0.040" 1033 10.2 10.1
0 26/34 SB
20 41/36 SB 0.038" 1025 10.0 10.2
0 41/36 SB
20 42/36 B 0.038" 1050 11.2
0 42/36 B
19 solid 0.036" 1290 8.37
13.2
20.5 27.4 19 solid
19 7/.0136 C 0.041" 1290
9 7/.0136 C
18 solid 0.040" 1620 6.64 6.64 6.68
10.5 16.3 21.1 18
solid
18 7/.0152 C 0.046" 1617 6.84 6.93
8 7/.0152 C
18 7/26 B 0.048" 1770 5.86 6.32 6.26
18
7/26 B
18 7/26 C 0.048" 1778 5.95 6.32 6.26
18
7/26 C
18 16/30 B 0.049" 1608 6.58 6.60
8 16/30 B
18 19/.0092 B 0.046" 1608 5.10
8 19/.0092 B
18 19/.0092 U 0.045" 1608
8 19/.0092 U
18 19/30 B 0.050" 1900 5.46 6.22 5.80
6.03 18 19/30 B
18 19/30 C 0.050" 1900 5.46 6.22 5.80
6.03 18 19/30 C
18 19/30 E 0.050" 1900 5.46 6.22 5.80
6.03 18 19/30 E
18 19/30 U 0.048" 1608 5.55 6.22 5.80
6.03 18 19/30 U
18 41/34 B 0.052" 1629 6.59 6.47
8 41/34 B
18 65/36 SB 0.051" 1625 6.39 6.40
8 65/36 SB
17 solid 0.045" 2050 5.26
8.29
12.9 17.2 17 solid
17 7/.0172 C 0.052" 2050
7 7/.0172 C
16 solid 0.051" 2580 4.18 4.17 4.02
6.59 22.8 10.2 13.7 16
solid
16 7/.0192 C 0.058" 2580 4.09 4.35
6 7/.0192 C
16 7/24 0.060" 2628 3.67 3.70
6 7/24
16 19/.0117 B 0.059" 2601 4.13 4.39
6 19/.0117 B
16 19/.0117 U 0.056"
6 19/.0117 U
16 19/29 B 0.054" 2426 4.27 4.82 4.54
4.73 16 19/29 B
16 19/29 E 0.057" 2426 4.27 4.82 4.54
4.73 16 19/29 E
16 19/29 U 0.054" 2407 4.47 4.82 4.54
4.73 16 19/29 U
16 26/30 B 0.059" 2613 4.11 5.59
6 26/30 B
16 65/34 B 0.063" 2584 4.16 4.02
6 65/34 B
16 105/36 RB 0.065" 2625 3.99 3.99
6 105/36 RB
15 solid 0.057" 3260 3.31
5.21 18.1
8.12 10.8 15 solid
15 7/.0216 C 0.065" 3260
5 7/.0216 C
14 solid 0.064" 4110 2.63 2.72 2.53
4.14 14.3 6.44 8.59 14
solid
14 stranded 0.073" 2.68 2.78
4 stranded
14 7/.0242 B 0.073" 4100 2.61
4 7/.0242 B
14 7/.0242 C 0.073" 4099 2.57 2.68
4 7/.0242 C
14 7/22 0.073" 4480 2.31 2.31
4 7/22
14 19/.0147 B 0.074" 4106 2.61
4 19/.0147 B
14 19/.0147 U 0.070" 4102
4 19/.0147 U
14 19/27 C 0.071" 3831 2.71 3.05 2.87
2.99 14 19/27 C
14 19/27 E 0.071" 3831 2.71 3.05 2.87
2.99 14 19/27 E
14 19/27 U 0.069" 3829 2.81 3.05 2.87
2.99 14 19/27 U
14 41/30 B 0.074" 4121 2.61 2.94
4 41/30 B
14 105/34 0.086" 4173 2.49 2.49
4 105/34
13 solid 0.072" 5180 2.08 2.16
3.28 11.4 5.11
6.81 13 solid
13 stranded 0.082" 2.12 2.20
3 stranded
13 7/.0272 C 0.082" 5180
3 7/.0272 C
12 solid 0.080" 6530 1.65 1.71 1.59
2.60 2.71 8.97 4.05 5.40 12
solid
12 stranded 0.092" 1.68 1.75
2.76 2.76
12 stranded
12 7/.0305 C 0.092" 6512 1.61 1.67
2 7/.0305 C
12 7/20 0.096" 7168 1.45 1.45
2 7/20
12 19/.0185 B 0.093" 6503 1.60
2 19/.0185 B
12 19/.0185 U 0.070" 6502
2 19/.0185 U
12 19/25 C 0.090" 6088 1.70 1.92 1.81
1.88 12 19/25 C
12 19/25 E 0.090" 6088 1.70 1.92 1.81
1.88 12 19/25 E
12 19/25 U 0.089" 6088 1.76 1.92 1.81
1.88 12 19/25 U
12 37/28 SB 0.072" 5913 1.62 1.72 1.87
12
37/28 SB
12 65/30 B 0.095" 6533 1.64 1.85
2 65/30 B
12 165/34 0.095" 6549 1.58 1.58
2 165/34
11 solid 0.091" 8230 1.31 1.37
2.07 2.15 7.15 3.21
4.28 11 solid
11 stranded 0.103" 1.34 1.39
2.19 2.19
11 stranded
11 7/.0343 C 0.103" 8230
1 7/.0343 C
10 solid 0.102" 10380 1.04 1.08 0.999
1.64 1.70 5.67 2.55 3.40 10
solid
10 stranded 0.116" 1.06 1.10
1.74 1.74
10 stranded
10 7/.0385 C 0.115" 10376 1.01 1.05
0 7/.0385 C
10 19/.0234 U 0.114" 10403 1.01 1.05
0 19/.0234 U
10 37/.0169 C 0.112" 9361 1.25
0 37/.0169 C
10 37/26 C 0.107" 9402 1.12 1.26 1.19
1.24 10 37/26 C
10 49/27 R 0.116" 10445 1.28 1.21
0 49/27 R
10 105/30 B 0.120" 10552 1.02 1.15
0 105/30 B
9 solid 0.114" 13090 0.824 0.848
1.30 1.35 4.49 2.02
2.69 9 solid
9 stranded 0.130" 0.841 0.874
1.38 1.38
9 stranded
9 7/.0432 C 0.130" 13064 0.82
7/.0432 C
8 solid 0.129" 16510 0.653 0.672 0.628
1.03 1.07 3.56 1.60 2.14 8
solid
8 stranded 0.146" 0.666 0.693
1.09 1.09
8 stranded
8 7/.0486 C 0.146" 16534 0.65
7/.0486 C
8 19/.0295 B 0.144" 16535 0.65
19/.0295 B
8 19/.0295 E 0.144" 16535 0.65
19/.0295 E
8 19/.0295 U 0.144" 16535
19/.0295 U
8 49/25 0.166" 16589 0.67
49/25
8 133/.0112 RC 0.166" 16851 0.645 0.679
133/.0112 RC
8 133/29 R 0.166" 16851 0.661 0.702 0.661
0.688 8 133/29
R
8 168/30 R 0.174" 16800 0.70
168/30 R
8 665/36 0.166" 16625 0.620
665/36
7 solid 0.144" 20820 0.518 0.533
0.817 0.850 2.83 1.27
1.69 7 solid
7 stranded 0.164" 0.528 0.550
0.867 0.867
7 stranded
7 7/.0545 C 0.164" 20820 0.526
7/.0545 C
6 solid 0.162" 26240 0.411 0.423 0.385
0.648 0.674 2.24 1.01 1.34 6
solid
6 stranded 0.184" 0.419 0.436
0.688 0.688
6 stranded
6 7/.0612 C 0.184" 26218 0.41
0.661
6 7/.0612 C
6 19/.0372 B 0.186" 26293 0.40
19/.0372 B
6 19/.0372 U 0.181" 26293 0.436
0.685
6 19/.0372 U
6 133/.0141 RC 0.212" 26440 0.406 0.430
133/.0141 RC
6 133/27 R 0.206" 26068 0.419 0.444 0.418
0.436 6 133/27
R
6 259/30 RB 0.210" 26029 0.417 0.437
259/30 RB
6 266/30 R 0.210" 26029 0.453
266/30 R
6 1050/36 0.204" 26250 0.386
1050/36
5 solid 0.182" 33090 0.326 0.336
0.514 0.536 1.78 0.799
1.07 5 solid
5 stranded 0.206" 0.333 0.346
0.545 0.545
5 stranded
5 7/.0668 C 0.206" 33090 0.331
7/.0668 C
4 solid 0.204" 41740 0.258 0.266 0.249
0.407 0.424 1.41 0.633 0.845 4
solid
4 stranded 0.232" 0.264 0.274
0.432 0.432
4 stranded
4 7/.0772 C 0.232" 41719 0.262
0.416
4 7/.0772 C
4 19/.0469 C 0.235" 41793 0.274
0.431
4 19/.0469 C
4 133/.0177 RC 0.266" 41668 0.256 0.271
133/.0177 RC
4 133/25 R 0.257" 42613 0.263 0.280 0.263
4
133/25 R
4 259/28 0.261" 41388 0.200
259/28
4 413/30 RB 0.266" 41506 0.261 0.274
413/30 RB
4 420/30 R 0.257" 42000 0.28
0.427
4 420/30 R
4 1666/36 0.290" 41650 0.250
1666/36
3 solid 0.229" 52620 0.205 0.211 0.197
0.323 0.336 1.12 0.542 0.744 3
solid
3 stranded 0.260" 0.209 0.218
0.343 0.343
3 stranded
3 7/.0867 C 0.260" 52620 0.208
0.330
3 7/.0867 C
2 solid 0.258" 66360 0.163 0.167 0.156
0.256 0.267 0.886 0.431 0.590 2
solid
2 stranded 0.292" 0.166 0.172
0.272 0.867
2 stranded
2 7/.0974 C 0.292" 66360 0.165
0.261
2 7/.0974 C
2 19/.0591 C 0.292" 66407 0.172
0.271
2 19/.0591 C
2 133/23 0.328" 67736 0.176
0.268
2 133/23
2 259/26 0.325" 65811 0.186
259/26
2 665/30 RB 0.342" 66832 0.162 0.183 0.169
2
665/30 RB
2 1666/34 RB 0.339" 0.163 0.173
1666/34 RB
2 2646/36 0.379" 66150 0.157
2646/36
1 solid 0.289" 83690 0.129 0.133
0.211 0.211 0.703 0.341
0.467 1 solid
1 stranded 0.332" 0.132 0.137
0.216 0.216
1 stranded
1 7/.1093 C 0.328"
0.207
1 7/.1093 C
1 19/.0664 C 0.332" 83771 0.137
0.207
1 19/.0664 C
1 133/22 0.365" 85439 0.121
133/22
1 259/25 0.375" 82983 0.144
259/25
1 817/30 0.382" 81700 0.146 0.149
817/30
1 2107/34 0.375" 83753 0.124
2107/34
1/0 solid 0.325" 105600 0.102 0.105 0.0983
0.168 0.168 0.557 0.271 0.371 1/0
solid
1/0 stranded 0.372" 0.104 0.108
0.171 0.171
1/0 stranded
1/0 7/0.1228 C 0.368"
0.164
1/0 7/0.1228 C
1/0 19/.0745 C 0.373" 105600 0.108
0.164
1/0 19/.0745 C
1/0 19/.0745 E 0.373" 105445 0.11
/0 19/.0745 E
1/0 37/.0534 E 0.370" 105508 0.10
/0 37/.0534 E
1/0 133/21 0.464" 107743 0.096
0.169
1/0 133/21
1/0 259/24 R 0.422" 104636 0.113
/0 259/24 R
1/0 1045/30 RB 0.431" 105022 0.103 0.116 0.108
1/0
1045/30 RB
1/0 2646/34 0.437" 105178 0.098
/0 2646/34
1/0 4214/36 0.490" 105350 0.098
/0 4214/36
2/0 solid 0.365" 133100 0.0802 0.0830 0.0779
0.133 0.133 0.442 0.215 0.294 2/0
solid
2/0 stranded 0.418" 0.0827 0.0860
0.136 0.136
2/0 stranded
2/0 7/.1379 C 0.414"
0.130
2/0 7/.1379 C
2/0 19/.0837 C 0.418" 133100 0.0860
0.130
2/0 19/.0837 C
2/0 37/.0600 C 0.420" 133200 0.08
/0 37/.0600 C
2/0 133/20 0.500" 135926 0.077
0.133
2/0 133/20
2/0 259/.0227 R 0.456" 129956 0.09
/0 259/.0227 R
2/0 259/23 0.414" 132297 0.090
/0 259/23
2/0 1330/30 0.494" 133665 0.081 0.0914 0.0852
2/0
1330/30
2/0 1330/30 R 0.496" 133300 0.09
/0 1330/30 R
2/0 3332/34 0.464" 132447 0.077
/0 3332/34
2/0 5292/36 0.486" 132300 0.077
/0 5292/36
3/0 solid 0.410" 167800 0.0636 0.0658 0.0618
0.106 0.106 0.351 0.170 0.233 3/0
solid
3/0 stranded 0.470" 0.0656 0.0682
0.108 0.108
3/0 stranded
3/0 7/.1548 C 0.464"
0.103
3/0 7/.1548 C
3/0 19/.0940 C 0.470" 167800 0.0682
0.103
3/0 19/.0940 C
3/0 37/.0673 C 0.470" 167584 0.07
/0 37/.0673 C
3/0 259/22 0.509" 166381 0.072
/0 259/22
3/0 427/24 0.536" 167401 0.072 0.059
/0 427/24
3/0 1519/30 0.574" 152659 0.061
/0 1519/30
3/0 1672/30 0.495" 168036 0.0678 0.0727 0.0678
0.109 3/0
1672/30
3/0 4256/34 0.555" 169176 0.061
/0 4256/34
4/0 solid 0.460" 211600 0.0505 0.0522 0.0490
0.0836 0.0836 0.278 0.135 0.185 4/0
solid
4/0 stranded 0.528" 0.0520 0.0535
0.0853 0.0853
4/0 stranded
4/0 7/.1739 C 0.522"
0.0820
4/0 7/.1739 C
4/0 19/.1055 C 0.528" 211600 0.054
0.0820
4/0 19/.1055 C
4/0 37/.0756 E 0.530" 211468 0.05
/0 37/.0756 E
4/0 259/21 0.606" 209815 0.055
/0 259/21
4/0 427/.0223 R 0.602" 212343 0.047 0.06
/0 427/.0223 R
4/0 427/23 0.605" 212342 0.047
/0 427/23
4/0 2109/30 R 0.627" 210900 0.0537 0.0576 0.0527
0.085 4/0
2109/30 R
4/0 5320/34 0.640" 211470 0.057 0.049
/0 5320/34
4/0 8512/36 0.655" 212800 0.049
/0 8512/36
Stranding:
* x/.yyyy means x strands of 0.yyyy-inch diameter wire
* x/yy means x strands of yy AWG wire
* B = bunched
* C = concentric
* E = equilay
* R = rope
* RB = rope/bunched
* RC = rope/concentric
* SB = smooth bunched
* U = unilay
Sources:
* Basic Electronics and Radio Installation (Crane)
* Carol Cable Company
* Electrical/Electronic Interconnection Systems 4th ed (Lawrence)
* Electrical Engineering Materials Reference Guide (Beaty)
* Electronic Designers' Handbook (Giacoletto)
* Electronic Engineers' Handbook (Fink)
* Electronic Engineers Master
* Electronic Failure Analysis Handbook (Martin)
* Electronics Data Handbook (Barden)
* Handbook of Wiring, Cabling, and Interconnecting for Electronics (Harper)
* Helix/Hitemp Cables, Bare Wire Technical Data
* Hitachi Electronic Wires and Cables
* http://www.interlog.com/~speff/usefulinfo/fusing.htm
* http://www.tridentalloys.com/impalloy/tablcond.htm
* Design Guidelines for Electronic Packaging Utilizing High-Speed Techniques
(IPC-D-317A)
* Madison Cable Corporation
* Manhattan Electric Cable
* Metro Wire & Cable
* MWS Wire Industries
* National Electrical Code 1990, Tables 310-16 through 310-19
* National Wire and Cable Corporation Master Catalog
* Phelps Dodge Magnet Wire Company, Engineering Data Copper Film Coated Magnet
Wire
* Reference Data for Radio Engineers, 2nd ed (Federal Telephone and Radio Corp)
* Royal Electric
* Standard Handbook for Electrical Engineers, 9th ed (Knowlton)
* The Design & Drafting of Printed Circuits (Lindsey)
* The Handy HamBook (Wagman)
* UL 1581 Reference Standard for Electrical Wires, Cables, and Flexible Cords
* Wiring and Cable Designer's Handbook (Matisoff)
ampacity.wir John Barnes 8/22/1999
John Barnes Advisory Engineer
Lexmark International
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This archive was generated by hypermail 2b29 : Tue May 08 2001 - 14:30:06 PDT