Re: Mains transformer only outputting 2V instead of 22V

Art Deco wrote:
On Fri, 22 Sep 2006 14:08:53 -0700, David Nebenzahl
<nobody@xxxxxxxxxxxxxxx> wrote:

Homer J Simpson spake thus:

"Art Deco" <erfc@xxxxxxxxxxxx> wrote in message
news:vab7h25ivpvghndmjid81hbopef0ksnsth@xxxxxxxxxx

No, that's all there is on the secondary side: four diodes and a
capacitor.
The primary side should be around 2,000 ohms (wide variation)

The secondary side should be around 10 ohms (wide variation)

If no continuity on either it's toast.
But the OP reported low voltage. A transformer is like being pregnant: either you is or you ain't. As you point out, either open or not. If open, zero volts. How do you get 2 volts?

I wonder if the OP was measuring correctly. (Don't laugh: the other day I measured something with a very low voltage; turned out I was trying to measure an AC source with my (analog) multimeter set on DC.)

Possibly the voltage I was reading was the residual voltage on the
capacitor, as someone suggested. In the event, it turned out to be
open circuit on the primary side.


If you had the meter on the ac range (as you should have to read the voltage on the transformer), you picked up a stray voltage...or not. If not, then more investigation is necessary. I believe somewhere in the thread, you stated the transformer was open on one side or the other. If that's the case, you picked up a stray reading...phantom reading which is indeed real, but not useful with respect to a determination of your problem.

jak

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