Replaced my cheap fan controller.
Here is some cut & pasted info...
"A variac is a vary simple device to use. It’s purpose is to raise or lower the voltage that enters it. Example: If your input voltage is too low – say 105 volts AC, you can just dial it up to the desired voltage, like 120 volts. If your input voltage is too high (130 volts AC) then you can lower it to your desired voltage (120 volts AC).
It does not automatically adjust voltages. That would be a line conditioner and much more expensive.
One application for a
variac is for use with coffee roasters (you need a good thermometer for this). By raising or lowering the output voltage of the variac into the coffee roaster you can manually regulate the temperature of the coffee roaster. This allows an inexpensive coffee roaster to rival the roasting qualities of much more expensive coffee roasters.
Another use is for cutting styrofoam. When a variacs output voltage passes through a nichrome wire it becomes heated and cuts the styrofoam like a hot knife through warm butter.
Almost everyone is familiar with a dimmer switch in their home to adjust the light output of a bulb. A auto transformer variac does the same thing by varying the output voltage to the device you connect into it."
A variac is a vary simple device to use. It’s purpose is to raise or lower the voltage that enters
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