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Re: Wire-wound resistors as dummy test load



Original poster: "robert heidlebaugh by way of Terry Fritz <twftesla-at-qwest-dot-net>" <rheidlebaugh-at-desertgate-dot-com>

Matt: I use wirewound resistors as dummy load and compensate for inductance
at the frequency I want. The 200-300 inductance range is what I have found
and yes they do vary fron production lot to lot, but the 508 is extream even
for resistors unless that one is a lower wattage and made with finer wire.
   Robert  H

> From: "Tesla list" <tesla-at-pupman-dot-com>
> Date: Mon, 30 Sep 2002 07:33:09 -0600
> To: tesla-at-pupman-dot-com
> Subject: Wire-wound resistors as dummy test load
> Resent-From: tesla-at-pupman-dot-com
> Resent-Date: Mon, 30 Sep 2002 07:43:58 -0600
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <Mddeming-at-aol-dot-com>
> 
> I found 4 200-Ohm, 200-Watt wire wound resistors all the same brand, that I
> thought I would string together as an 800 Ohm, 800 Watt, test load for my TC
> power supply, while checking things such as PFC cap size, etc.  However, when
> I
> checked them with my meters, I got these readings:
> 
> 1) 205 Ohms 339 uHy
> 2) 206 Ohms 221 uHy
> 3) 210 Ohms 225 uHy
> 4) 208 Ohms 508 uHy
> 
> Physically, they all seem to be the same size, shape, and construction, but
> the
> variation in inductance seems unreasonable. Has anyone looked into the
> inductance of wire-wound resistors before? If so, is this reasonable? I know
> that at 60 Hz, this only amounts to about 0.1 to 0.2 Ohms inductive
reactance,
> but it seems strange.
> TIA,
> Matt D.
> 
>