[Milsurplus] Back to the drawing board...

[J. Forster]

Rick Brashear wrote:

> Thanks again for all of the assistance on the high LV problem.  Now I
> have discovered I have maybe an even bigger problem.  My transformer
> seems to be drawing excessive current, about 19 AMPS, when totally
> disconnected from the rectifiers and filter capacitors and no other load
> on the secondary.   I know nothing about this transformer, there are few
> markings and none that identify the maker or model.  However, when I
> received it there was an AC capacitor (like a motor starting capacitor)
> attached to a set of lugs marked "CAP".

It's a 'constant voltage transformer' Google 'sola' or 'ferroresonant' You NEED
the capacitor. Also, the variac or buck transformer may not work  properly. It
will draw excessive current w/o the cap at line voltage, because the resonant
circuit is not.

-John



>  Unfortunately, that capacitor
> is shorted.  This is new territory for me or possibly my memory is again
> playing tricks on me.  Does anyone have any experience with a
> transformer like this?  The connections are:
>
> Primary
> Secondary with center tap
> CAP
>
> All are clearly marked.  I think it may be out of an old (AC/DC) arc
> welder or a very hefty battery charger.
>
> Any ideas?
>
> Rick
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