Hey Rob...It is normally used to ramp up the voltage to the NST during testing and slow starting the coil. It makes a nice safety factor instead of having the coil kick in at full throttle when turned on elsewise. Plus having the few extra volts the variac supplies, allows the coil to produce a couple of more inches of streamer.
Genrally the variac has a phenolic plate on the unit where the attach points are and there is a "schematic" on the plate showing the hook ups ( in most cases).
check out this site for more info on variac wiring and paralleling http://members.cox.net/bunnikillr/parallel.html Scot D stamsund wrote:
I found a variable transformer among my shop goodies. It's a Superior Electric Powerstat, Model Q116U, 120 volt primary, 0-140 volts out, 1.3 KVA, 9 Amps. I understand it should be used between AC power and the NST, but I'm not really sure why it's needed and/or recommended and exactly how to connect it.Rob Robertsen, KA7YAK _______________________________________________Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla
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