Staco variac rating differences

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Richard Williams by way of Terry Fritz <twftesla-at-qwest-dot-net>" <richardwwilliams-at-earthlink-dot-net>

Hi List,
 
I've recently aquired another variac. I have two Staco variacs, 2510s, rated at
140v -at- 25 amps,120v input and has 5 terminals.
The third, type 033-6565, the one I just got, is rated at 20 Amps 0-180V, input
120V but has only 3 terminals. ??????? huh?
 
Some physical characteristics:
 
-The wire size is the same for all 3 variacs, #12.
-All have the same brush, interchangable, with no apparent differences in size
or shape. Totally alike.
-The winding of the 033-6565 is about 3/4" taller than the 2510s but has the
same diameter. 
-The mounting hole "footprint" is also identical for the 2510 and 033-6565. 
-Shaft sizes are alike at 1/2" diameter. The lengths are the same.
 
I have several questions:
 
1) How can the 033-6565 have 120 input and 180 out with only 3 terminals? Or am
I reading this the wrong way?
 
2) Will the 033-6565 also handle 25 amps if kept to 120 volts?
 
3) Anyone know a good place to get brushes for Staco variacs? I've emailed
Staco but no response as yet, been a couple days now.
 
I got it from Ebay for $40. All it needs is a brush. Everything else is in
great shape.
Can be viewed here....
<http://www.fairradio-dot-com/variac.htm>http://www.fairradio-dot-com/variac.htm
 
I didn't need the motor.
 
Thanks all !!
 
Rick W.
Salt Lake City