Re: Dumb question ...




"Rich Webb" <bbew.ar@xxxxxxxxxxxxxxxxxx> wrote in message news:gugp5392rv1fj1hgb7ccucfnd3j8ggv4iu@xxxxxxxxxx
On Tue, 29 May 2007 23:35:17 GMT, "Jeff Strickland"
<crwlr@xxxxxxxxxxx> wrote:

... mostly because I'm dumb.

What's the difference in a volt-amp and a "regular" amp?

I have a transformer that makes 24vAC, and is rated at 40 VA, but the amp
rating is only 1.67.

I have a lamp (fiber optic system) that takes 24v and 250W, which works out
to 10.4A. The VA rating does not give me the current I need, and when I plug
the light in, the voltage drops because the draw exceeds the power by a wide
margin.

http://en.wikipedia.org/wiki/Volt-amp is a starting point. To avoid
recapitulating what's explained better and in more detail elsewhere,
volt-amps and WATTS (not "'regular' amps") are the related
measurements.


Okay, so to distill it down, 40VA is not near enough to drive a 250w light?

Actually, this is a bit moot because another multi meter in my fleet has determined that the lamp is open. I can't explain why I couldn't figure this out before I bought the new power supply ...




.



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