How many volts does a ballast put out?
Just so, what is the output voltage of a t12 ballast?
When power is first applied, a high voltage (several hundred volts) is needed to initiate the discharge. However, once this takes place, a much lower voltage - usually under 100 V for tubes under 30 watts, 100 to 175 volts for 30 watts or more - is needed to maintain it." Fluorescent Tube and Switching Ballasts.
Also question is, what is inside a fluorescent ballast?
An inductor is very common in line-frequency ballasts to provide the proper starting and operating electrical condition to power a fluorescent lamp, neon lamp, or high intensity discharge (HID) lamp. (Because of the use of the inductor, such ballasts are usually called magnetic ballasts.)
A replacement ballast costs about $10-25 depending on capacity and brand. The bite is that an electrician trip charge (which includes 30 or 60 minutes work) is going to be $75-150 probably - for about 5 minutes work on each light fixture.