Tracing short in fluorescent lighting fixtures

[1190R]

I demoed my barn and moved everything into a large storage tent. I daisy chained 3 fluorescent lighting fixtures and everything was good for a week. Now my spider box breaker trips every time I turn on the lights. What is the best way to figure out where the short is?

 

[PoorUB]

Unhook the last in the chain and try turn them on, if the breaker trips, then unhook the second and try again, if the breaker trips, then unhook the first in line and try it. If it still trips you need to look over the wiring.

There is a good chance if you just open up the lights you may find a wire nut off and arcing to the fixture. Look for burned spots.

 

[Terry D]

Were they used lights. Could be a bad ballast. Since its only 3, eliminate one fixture at a time. What is a spider box?

 

[1190R]

Thanks poor. That's what I was thinking but didnt know if there is an even easier way

 

[1190R]

Thanks Terry. Yes, they're old but worked a month or two ago

 

[Leaflessshadetree]

Look for black marks, especially by wire nuts and fittings/clamps. hard edges etc.

 

[fitter30]

Ohm meter to ground wire

 

[PoorUB]

Thanks poor. That's what I was thinking but didnt know if there is an even easier way

With only three lights it won't take long.

Like I said before, if you take a look at the wiring and ballasts you might find something obvios, a burn mark, or cooked ballast.

 

[walta]

You may want to consider the spider box is tripping off because it is detecting a ground fault and not because of over current. A GFIC will trip for only .02 amps current difference between the black and white wires.

I would start in the center of the circuit and disconnect both the black and white wires then see if it still trips. The GFI fault could be inside of one of the ballasts or the white wire may have been pinched and after some time the insulation got cut thru or some water may have found a way inside the fixture.

Walta