Low earth current leakage Ballasts

[Kopper]

The fact that one light turns on by itself, the fact that an electronic ballast does leak some current, the technician's confidence that an electronic ballast will cause issues on a Ground Fault protected circuit, the fact that the trailer was plugged into a job site circuit with various other items plugged into it lead me to believe that there was too much current leakage which caused the breaker to trip. I have not had opportunity to plug it into a GFCI only but will still try that. I am suspicious that if two lights are the only items on the GFCI that it may not trip the GFCI but coupled with other items it simply makes to much leakage and causes the device to detect a fault.

 

[winnie]

I know that the general consensus on this forum is 'if something leaks current to ground then it is broken'. I happen to agree for the most part: if a piece of equipment that can be plugged into a 20A circuit trips a GFCI, than that equipment is likely broken.

However this must be understood to be an approximation: everything leaks current to ground to some small extent.

Fluorescent lamps are known to interact and couple to ground. Consider than many fixtures won't reliably start unless the chassis is grounded; the capacitive coupling between the lamp tube and the chassis makes it easier to start the lamp. This means that some current _must_ be flowing to the chassis via capacitive coupling.

Higher frequency operation (eg. using an electronic ballast) will increase this current flow.

It would not surprise me if this ground current is transient, right at startup of the lamp.

Question: what happens if these lamps are switched on separately, so that you first turn one on, and then the other?

-Jon

 

[Kopper]

Thank you Jon for your contribution. I said I would try the lights on a gfci. I did that and they tripped the GFCI receptacle. I did not try starting one and adding the other. I did try each of them separately and the on light tripped the GFCI pretty well every time while the other would start and be fine at least sometimes. The plan is to get other lights so they will work. Thanks to all of you who gave valuable contribution to the issue here.

Cheers,
Kopper

 

[K8MHZ]

The two lamp 4 ft t-8 shop light in my garage is plugged into a GFCI rec.

Me too, except mine are hard wired to the load side of a GFCI receptacle. No problems at all.