Re: Calculating the drain I - SSTC

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

Hi Sue,

The #10 wire is 0.1019 inches in diameter.  The skin depth is 0.00553 
inches.  So, we can find the conductive area and the resistance.

area = pi x r^2
outside = 3.14159 x (0.1019 / 2)^2 = 0.008155 square inches
inside = 3.14159 x ((0.1019 / 2) - 0.00553)^2 = 0.006481 square inches

0.008155 - 0.006481 = 0.0016739 square inches of conductive area.  That is 
the same area as #17 wire (.0016089) which has a resistance of  0.00516 
ohms per foot.  At 4 amps, every foot of wire will dissipate

0.00516 x 4^2 = 0.08256 watts

It is really not that exact, but it should be sort of close.

So if I have not messed up anywhere, your wire should stay cold and have 
only tiny loss.

Cheers,

         Terry



At 09:08 AM 12/27/2003, S.Gaeta wrote:
>Thanks to every one who replied!
>
>Terry, The primary is 11 turns of #10 wire. All I had of this size was a
>very bright lemon yellow color. A little too cheerful and sunshiny for a
>project like this, but what the hey, the electrons can't tell the difference
>anyway.
>
>I have a lot of different answers to work with now! The FETS are spec'ed out
>at 20 amps max, so I'll just put a 15 amp fuse in the DC, cross my fingers,
>and hope for the best!
>
>Thanks,
>Sue