GFCI AND LAMP FAILURE TROUBLE REPORTED
* Premature lamp failure (1 year lamp failure) for T5 8W tubes operated intermittently in single-family home’s kitchen.
* Switched lighting circuit serving electronic ballasted fixtures trips 20A breakered GFCI countertop receptacle
The under cabinet lighting (6) fixtures ranging 8 to 32W each running one or two T5 lamps each, on electronic ballasts, all on the load side of a countertop GFCI receptacle.
Load Testing
* Starting at 9:40am today, I ran a hair dryer (motor and resistive heat) load, on low setting (1200W ??), on the wires feeding the under cabinet light where the customer most recently had lamp outage.
* With (5) remaining electronic ballasted T5 fixtures remaining in the switched, GFCI-protected circuit, and the hair dryer at low setting (1200W out of 2000W high setting?), the GFCI and circuit breaker continue to hold to 10:05am.
* Increasing hair dryer setting to high (2000W), for 1min, still no trip.
Product Research
An online search has turned up the interesting fact that electronic ballasts in newer fluorescent fixtures may be required to use radio frequency interference suppressors, that can cause an imbalance of current on the phase and neutral conductors of the circuit. This electromagnetic line loss on one side of the two-part circuit may appear to be a ‘fault’ to the ground fault circuit interrupter, causing it to trip.
I’m no expert, but this is what my understanding is based on asking around:
1) Electronic ballasts have to have RFI filtering in place to comply with device regulations. This RFI filter bleeds up to 1/2 amp.
2) GFI doesn’t care about surges, etc — only about a current flow mismatch between hot and neutral.
3) Because there is an inherant mismatch of current with the RFI circuit bleeding energy, the GFI can trip.This apparently doesn’t happen with magnetic ballasts because they don’t have the RFI circuit. It can also apparently be hit or miss with electronic ballasts depending on how much current is being bled by the RFI circuitry.
FWIW, I too had my lights on an aquacontroller with a lot of other things. When my new lights tripped my GFI it shut the whole tank down. I am now handling this by adding a DC4-HD for my lights only — hooked up to its own GFI, and then I’ll run the rest of the items, heaters, fans, pumps, etc. on my DC-8 which will be on its own GFI. That way if my lights trip a GFI, everthing else will keep on ticking…
Jack
http://www.reefcentral.com/forums/showthread.php?s=5c8f91ad2e69776cff4dd827017bd84c&t=862403
01-15-09, 01:00 PM #12
gar Senior Member
Join Date
Apr 2008
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Ann Arbor, Michigan
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090115-1140 ESTyankj and luggem:
Using my test Leviton 7899-W device I have discussed in a different thread I got the following results:
1. 8 ft Slimline magnetic ballast and no RFI filter.
— many tries and I could not trip the GFCI.
2. Same as (1) but includes an RFI filter.
— tripped on the first try. Obviously this one has a EGC to the lamp and the filter has capacitors from the supply lines to the EGC.
The filter current to EGC is about 20 MA.
See also:
Licensed Electrician Robert Monk Electronic ballast fluorescent fixtures trip GFCI due to RFI suppression circuit? Copyright Robert Monk, 2012
licensed electricians residential electrician electrician company electrician tools electrician commercial
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