Re: Motorized Variac question . . .

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

Original poster: "David Speck by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dave-at-davidspeckmd-dot-org>

FWIW,
Certainly, the variac wiper will mechanically stop when it hits the end 
of its travel.  However, it is best to have a pair of microswitches 
arranged to stop rotation in the appropriate direction before you hit 
the stop hard.  The switch should break the motor circuit just as the 
wiper reaches the end of the travel.

>>2.  Do these motorized variacs have mechanical limits on them,
>>
>>	(A manual variac can ALWAYS be spun down.  An motorized
>>	one...)
>>    
>>
My control panel has a big master cutout latching relay circuit which 
separates the mains from all internal components, including the variac. 
 I can hit the bit red mushroom switch button a lot faster than I can 
spin a big variac down to zero, and it kills both the MOT bank and the 
rotary gap simultaneously.
Dave