I'm not very strong with electrical, but I can do basic repairs. I plugged an extension cord in and somehow the 15 amp GFCI in my garage blew. I replaced it with a new 15 amp GFCI. I now have power to my garage and outside outlets except an outside GFCI by the front porch. I'm going to test for power with a multimeter and replace if necessary (hopefully an easy fix ). My main issue is now every time I switch on my fluorescent shop light (four foot, 2 bulb, plug in type) in a different outlet, it trips my new GFCI. Anything else I plug in is fine. I never had that issue before. I've recently been doing a lot of sanding. Could the sawdust be affecting the Ballasts and causing a short?

Any advice from you experienced electrical guys/ladies? I'm on a 20 amp breaker by the way.

Thanks in advance

  • Do you have any other GFCI outlets in your house you can the light with, perhaps in a bathroom? – DarthCaniac Sep 15 '15 at 16:58
  • It's more likely that the high startup cost of a fluorescent light is being sensed by the GFCI and tripping. Refrigerators, pumps, A/C Motors and similar are also known to do this. Most likely all of this is downstream of your new GFCI. – BrownRedHawk Sep 15 '15 at 17:40
  • A GFCI should not be tripped by excess current (even inrush). It rather sounds like your FL light has a ground fault, exactly like the one GFCI is designed to detect. As your old one "blew", it can be assumed that it didn't worked properly. Try running your light with the tubes removed - if it trips, then the fixture is faulty and needs to be fixed. Sadly, FL tubes sometimes "just" trip GFCIs and there is nothing that can be done about it except getting a different fixture (especially a fully insulated, plastic one, without ground wire). – Agent_L Sep 16 '15 at 10:28
  • Flouresent lamps can be the cause in rare cases with GFCI'S , I normally say B.S. to this but have seen it happen where an older set of lamps was tripping a GFCI after installing new lamps it was fine. I had isolated everything on that circuit. My best guess since I did not measure enough (just under 3 ma) to trip the GFCI because of the old lamps. The heavier load on the switching supply (ballast) was creating enough additional harmonics that was causing the trip. After tracking it down I isolated the ground from the ballast to see if it was leaking not with the new lamps yes with the old. – Ed Beal Nov 13 '17 at 14:21
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    hey "community" quit dredging up old questions. 2 years old, the OP never responded to basic questions. Why wast time? – agentp Dec 14 '17 at 1:27

don't think the sawdust is the problem, but you might want to check to make sure your bulbs are making good contact. they could be causing an intermittent power surge by not being in the socket completely and causing it to trip. more than likely you have a sensitive gfci.

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