Re: shielded motor cable

Hi Ray,

I plugged your formula

diameter=0.32486...x(0.89052...)^size in.

into a spreadsheet and the result came out as below. Would that be
about correct? Turns out #20 was 0.0426 in.

size solid stranded
0 0.3249 0.4331
1 0.2893 0.3857
2 0.2576 0.3435
3 0.2294 0.3059
4 0.2043 0.2724
5 0.1819 0.2426
6 0.1620 0.2160
7 0.1443 0.1924
8 0.1285 0.1713
9 0.1144 0.1526
10 0.1019 0.1359
11 0.0907 0.1210
12 0.0808 0.1077
13 0.0720 0.0959
14 0.0641 0.0854
15 0.0571 0.0761
16 0.0508 0.0678
17 0.0453 0.0603
18 0.0403 0.0537
19 0.0359 0.0479
20 0.0320 0.0426
21 0.0285 0.0379
22 0.0253 0.0338
23 0.0226 0.0301
24 0.0201 0.0268
25 0.0179 0.0239
26 0.0159 0.0213
27 0.0142 0.0189
28 0.0126 0.0169
29 0.0113 0.0150
30 0.0100 0.0134

This is very useful. Got any more secrets?

--- In CAD_CAM_EDM_DRO@y..., "Raymond Heckert" <jnr@a...> wrote:
> >04" dia solid wire is about 1600 CirMils, Stranded wire is probably
> 75% as dense as solid, so you've probably got about 1200 CM, say,
#20
> ga; 'ampacity' of about 5 amps, continuous duty. If you're gonna
use
> 'chopped' signals, you could probably push 8 amps. Are the
individual
> strands about 0.2mm dia (#32 ga)?
>
> Speaking of wire size, did you know that wire dia (in INCHES) is
equal
> to 0.32486077638 times (0.89052571473 raised to the wire size #),
then
> round to 0.xxxx, [i.e. 4 decimal places]? this works from wire size
0
> (aka 1/0) thru #50. I used this relationship in a 'quick-and-dirty'
> transformer sizing program that I used for quoting 'ballpark' prices
> 'off-the-cuff". The number .890... is the 39th root of 1/92, the
number
> of times #36 wire (.0050" dia) is compared to 4/0, ( .46000").
Thirty
> nine is the number of geometric-progressive steps between #36 &
#4/0.
> The .324... is the calculated wire size for #0 ga wire. There! Now
> everybody knows one of my dirty little secrets! Always get more than
> you asked for...
>
> RayHex