ECN Forum Forums General Topics of the Trade General Discussion Area 2000 watt movie lamp trips GFCI

I have a customer who's brother is in the filming business. He has a 2000 Watt lamp that he says trips the GFCI every time he powers it up. The filming area is all GFCI protected. The best explanation I can come up is the high inrush from the cold tungsten filament must be causing an imbalance between the line/neutral enough to trip the GFCI. I suggested using a dimmer to bring the lamp up slower.Am I even on the right track?

Is it a gfci breaker or receptacle? What is the rating of the breaker?

It's a GFCI receptacle, 20 amp on a 20 amp ckt with downline receps on it's load side. The light works fine on a non GFCI 20 amp circuit. I thought at first maybe a ground/neutral fault in the fixture, then I thought about the inrush.

Well I know that some reactive circuits trip GFI's but if this is a total resistive circuit it should work fine. Is it a total resistive circuit? 16.6 A is high for that circuit anyway. But if its only on now and then it should be fine.

[This message has been edited by RobbieD (edited 12-05-2004).]

if the light MUST be GFCI protected, and there are nobody else can think of a better idea, then try using a dimmer switch on the light. make sure it has a 2000 watt capacity. with the dimmer you could bring the bulb up to full power slowly, reducing the inrush.

Coming from the one 2000 watt lamp alone you have the 16.6 Amps, With basic ohm's law. let alone what else is on the circuit. It's probably a good chance it is overloaded.

Can you not just use a GFCI class 'B' instead to prevent nuisance tripping in this case?

-Greg

"Coming from the one 2000 watt lamp alone you have the 16.6 Amps, With basic ohm's law. let alone what else is on the circuit. It's probably a good chance it is overloaded."

I thought it was a misconception that a GFCI receptacle will trip on overload. I thought it would only trip on ground fault.

I think I will ask him to let me check out the lamp, just to satisfy my curiosity.

Your right GFCI receptacles do not trip on overcurrent.

Why are GFCI receptacles being used there anyway? This a kitchen show? I'm for using GFI's where required but if you use them everywhere because you are paranoid you are going to have problems like this.

-Hal