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Re: VARIAC's -> parallel??

At 07:39 PM 11/12/98 EST, Jim Monte wrote in part:
>
>
>How much does each variac weigh?  A 30A variac for 240V input will
>probably weigh nearly 100 lbs, so if each array weighs around 500 lbs,
>it should be possible to parallel connect them for a 6*30A = 180A -at-
>240V variac.  That's over 40kVA, which would handle all but the
>largest systems.  It they are in good condition, that is a really good
>deal for $200!  Would you give more information about how to contact
>the salvage yard?
>
>Jim Monte
>

	My friend was talking to an engineer at a variac company the other day.
He warned against putting variacs in parallel.  Apparently, if the output
voltage of each variac is a little different, there will be heavy current
flow between the outputs due to the unbalanced voltage.  He had some
special choke or something for $100 that would fix this problem and allow
them to be put it parallel.  Anybody ever heard this before??

	We decided it was ok because we put the ballast resistors on each leg of
the three phase variac and then combined them.   So the resistors would
balance the voltages out before they were joined.  The engineer's concern
did seem very valid to us.

Something to ponder...

	Terry