110 Volts Power Supply

[Chris Suslowicz]

Originally Posted by Bob Carriere

Meanwhile check my pictures of the Variac I repaired.

Of course now I have question about the Variac.

Using a voltmeter I have confirmed that the numbers on the Variac dial are + or - 1 or 2 volts.
At 30 volts on the Variac dial I get 31.5 volts and the light is orange dim. 70 volts brighter

The strange thing is that it inputs 120.4 on the INPUT line but can actually put out a max of 137.5 volts ....... which made the lamp very very bright.

So I have concluded that the Variac is not only an adjustable voltage control but also capable of multiplying what is actually coming out.
Bob C

Yes, a variac is actually a variable transformer and can step the voltage up (slightly) as well as down. This can be useful if your AC supply voltage normally runs a little on the low side.