Need help with bad T5

[Loc Dog]

I bought a 4 bulb 4 foot T5HO months ago. After about a month 2 bulbs went out, and company sent new ballast. Finally got around to it since it was going to be bitch to disassemble.

Swapped it out, turned it on and those banks came on for a second before tripping GFCI.

Can someone help me troubleshoot it? it is made by Lightwise.

Thanks!!

 

[OldPhart]

Well, you are looking for a 'Ground Fault'. This can be caused by a fault in the lamp it's self. This means that there would be a wire touching the chassis. This could be either the neutral, the line (not likely, because either the GFCI or breaker would trip instantly.), or one of the wires or sockets going to the bulbs. The fact that it works at all would tell me that it isn't a major fault. I would suspect that maybe the neutral or one of the leads going to the sockets/bulbs is making very slight contact with the chassis. Now for one of the stranger things that can cause the GFCI to trip is a 'Ground Loop". What this means is that the ground on the chassis is at a different 'ground' potential than something it is touching. This is often something such as a cold water pipe, or another appliance plugged into a different circuit; but could be something as simple as a metal shelf sitting on a concrete floor. The simple way to test this is to insulate the lamp from any conductor that is at a different ground potential. The easiest solution is to hang the light on a string, or put bits of cardboard between the light and any other metal, and see if the issue goes away. Trouble shooting a flaky GFCI situation can be a real pain in the ass, good luck.

PS, this could also be a sign of a flaky balast, if there is something 'leaking' a little current to the chassis.

 

[Loc Dog]

Well, you are looking for a 'Ground Fault'. This can be caused by a fault in the lamp it's self. This means that there would be a wire touching the chassis. This could be either the neutral, the line (not likely, because either the GFCI or breaker would trip instantly.), or one of the wires or sockets going to the bulbs. The fact that it works at all would tell me that it isn't a major fault. I would suspect that maybe the neutral or one of the leads going to the sockets/bulbs is making very slight contact with the chassis. Now for one of the stranger things that can cause the GFCI to trip is a 'Ground Loop". What this means is that the ground on the chassis is at a different 'ground' potential than something it is touching. This is often something such as a cold water pipe, or another appliance plugged into a different circuit; but could be something as simple as a metal shelf sitting on a concrete floor. The simple way to test this is to insulate the lamp from any conductor that is at a different ground potential. The easiest solution is to hang the light on a string, or put bits of cardboard between the light and any other metal, and see if the issue goes away. Trouble shooting a flaky GFCI situation can be a real pain in the ass, good luck.

PS, this could also be a sign of a flaky balast, if there is something 'leaking' a little current to the chassis.

Thanks!!

That is what I get buying the cheapest I can find. It worked for about a month. I just swapped out the ballast. It was not on GFC! circuit before, so maybe it ran with the ground fault, then burned out ballast?

Would the neutrals be the whites and yellows (they are connected together). Have another smaller unit that works. Will play around with continuity between bulb contact points and frame.

It is a shame, because it was nice for young plants without jumping to 400 watt. They have stranded wire connect to solid with wire nuts, and did pretty lame job. Really going to have to disassemble down to chassis.

Be well!!

 

[OldPhart]

Thanks!!

That is what I get buying the cheapest I can find. It worked for about a month. I just swapped out the ballast. It was not on GFC! circuit before, so maybe it ran with the ground fault, then burned out ballast?

Would the neutrals be the whites and yellows (they are connected together). Have another smaller unit that works. Will play around with continuity between bulb contact points and frame.

It is a shame, because it was nice for young plants without jumping to 400 watt. They have stranded wire connect to solid with wire nuts, and did pretty lame job. Really going to have to disassemble down to chassis.

Be well!!

If they have connected the neutral and ground together, that would cause the GFCI to trip. unfortunately colors could be what ever they want, a lot of manufacturers will use whatever they want/have on hand. I would start by testing the continuity between the ground pin and the line/neutral on the plug. If you find ANY continuity between the ground and line/neutral I hate to suggest it, but I think I would get one of those gray 2-3 ping adaptors, and see what happens when the ground pin is disconnected. This could allow the light to deliver a pretty nasty 'zap' if something is wrong with the light, but the GFCI would shut it down before anyone would die. That is kind of their purpose.

PS, the more I think about it, I think I would not fool with lifting the ground... need to determine the cause of the fault. I have had a couple complex situations where I had to lift the ground due to induced currents on the ground leg, that I could only be resolve by lifting the ground pin on one of the devices. This doesn't sound like the case here. Grounding can be a crazy situation, because there is no such thing as a single ground. You can drive in a 'perfect' ground rod into the earth, and drive another 'perfect' ground into the earth 20 feet away, and guess what, there will be/could be a difference between them.

I just wanted to point out what a GFCI does. It monitors the current flowing through all three wires. If it detects ANY difference in current between the 'line' and 'neutral' lines it trips; because it means that the current in the circuit is finding another path to flow, like through a human. It is able to detect VERY small differences, like a fraction of a milliamp. The other thing it does is monitor the 'ground' circuit for ANY current flow. This is why if the ground/neutral pins are connected, it will cause them to trip. The one thing that a GFCI does NOT do is protect you from over current conditions. As long as the load is balanced between the line/neutral lines, it could be ANY current level. That last one is a pet peeve of mine, a lot of people think that a GFCI can do the job of a circuit breaker, but it does NOT; you still need to have the circuit breaker sized to protect the wiring.

 

[Loc Dog]

I can not believe the response I got from the e-bay seller. They said it was not compatible with a GFCI circuit. Unless the ballast has a massive power-on spike, I do not believe it.

 

[OldPhart]

I can not believe the response I got from the e-bay seller. They said it was not compatible with a GFCI circuit. Unless the ballast has a massive power-on spike, I do not believe it.

That sucks, they know it isn't wired properly.

 

[Loc Dog]

It actually does work on regular outlet. Can an electrician explain why it would work there, but not with GFCI?? I am just wondering if their is minor problem that will kill the ballast again in a month.

 

[Floridian]

It's because a GFCI and equipment grounding outlet work differently.A GFCI is for personnel protection and works on a very small difference between line and load current I think it's 5ma,another words the difference in current flowing between the hot and neutral wire,the ground plays no part.In a regular receptacle the fault is determined between the line and the equipment ground not the noodle.Some circuits especially motor circuits don't work well on GFCI circuits