Watts divided by voltage equal amps.
A 400 watt ballast plugged into ordinary house current (120v) would draw 3.33 amps.
Using a little math we can see then:
Amps = Watts / Voltage
Watts = Voltage x Amps
Voltage = Watts / Amps
Watts divided by voltage equal amps.
A 400 watt ballast plugged into ordinary house current (120v) would draw 3.33 amps.
Using a little math we can see then:
Amps = Watts / Voltage
Watts = Voltage x Amps
Voltage = Watts / Amps