11-15-2014, 03:38 PM
You do not need a meter in the Variac.
Just increase the votage until you have 300mA through or or 6.3V across a filament that is 6.3V while with the lamps in place. Measure the otal voltage then across the whole string (all filaments etc). Then you know exactly what you need to drop which is your MAINs minus what you have measured.
Just increase the votage until you have 300mA through or or 6.3V across a filament that is 6.3V while with the lamps in place. Measure the otal voltage then across the whole string (all filaments etc). Then you know exactly what you need to drop which is your MAINs minus what you have measured.
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