GFI's

[randoma]

I have a 15amp GFI on our 90 gallon reef (currently in the kitchen - Mauro's fault). Last night, at some point, for no apparent reason, it tripped.. (I guess I can blame that on Mauro too! ) Current draw, particularly at night, is around 500 watts, assuming the heater is on, so draw is way less than 15amps. Nothing was wet. There's no wavemaker, so the only thing turning on/off is the heater which is a resistive load and shouldn't cause a spike..

This is not the first time I've had trouble with a GFI.

So... On one hand I'm kinda nervous about getting electrocuted. But at the same time, I don't really want to come down in the morning and find the tank at 70F again. I'm just glad I have half the powerheads on a separate circuit so at least there was still water flow.

Anyone else have problems with GFI's? Any reasonable solutions?

 

[stevenp]

Is it a GFI recep or a breaker? I've had the receps pop on me from time to time but have never had any problems with the GFI breakers that I have my tank circuits running on (knock on wood).

 

[NateHanson]

If the GFI is popping, it's not an over-current problem, but a leaky current problem. Somehow electricity is getting to ground. It could be a moist powerstrip, or a bad pump or something.

Or it could just be a cheap, oversensitive GFI receptacle. I'd probably start by buying a new receptacle, and try it that way. Also inspect all the obvious places for ground faults: damaged cords, wet or salty powerstrips, etc.

 

[willray]

Is the gfi independant or connected to another outlet,light switch...nothing else is on the circuit?

 

[mgreefer]

I had the same problem with the GFI’s you buy from home Depot or similar stores. They tend to trip if they get a sudden current overload even though the load is below their Amps rating.

I had 20amps GFIs when halides go on all at once it trips even though the load from the bulbs is only 10amps and nothing else is on the circuit it is dedicated to the tank’s light. If I turn the halides one at a time there are no issues and I know that electricity is not getting a ground.

Anyway I ended up changing them to the commercial grade GFIs never had an issue since then. I recommend getting the commercial grade from an electric supply store

 

[Dragon2115]

If you have one, take a volt meter and drop one lead in the sump and the other in the ground (center, or third prong) of the outlet and see if there's any voltage there. You may need to isolate things from ground one at a time using one of the three-prong to two-prong adapters to see if anything is trying to leak to ground. Be careful, setup the meter first and then isolate things. That way if there is a bad component you won't get shocked by touching the water while taking the reading. GFI's, iirc, only take 27 mA to trip.

mgreefer, the reason your breaker was tripping is because the in-rush current of your lights both turning at once exceeded the breaker. Electrical devices can have large in-rush currents even though their running currents are much lower. I used to work with electric motors on pumps and with a running current of 18 amps the in-rush at startup was over 300 amps. Needless to say that when we ran multiple pumps we had to sequence turning them on or we'd trip breakers as well. If your running current is 10 amps then I'd take a guess that your in-rush current is somewhere around 50 to 60 amps which is enough to trip the breaker. With one light turning on it's probably more like 20 - 30 amps which the breaker can handle. The reason is the in-rush is very short in duration and breakers are notoriously slow reacting.

 

[mgreefer]

Dragon2115, thanks for explaining it makes sense. I am just disappointed at manufacturers, 2 GFI products same specifications (both 20amps), one sells @home depot obviously for home DIY the other is commercial from electric supply store, they are even the same price, the one for home trips at rush current but the commercial doesn’t.

P.S. it is not the breaker that was tripping it is the actual GFI outlet and you have to press reset to turn it on again.

 

[JayM]

Dragon2115, thanks for explaining it makes sense. I am just disappointed at manufacturers, 2 GFI products same specifications (both 20amps), one sells @home depot obviously for home DIY the other is commercial from electric supply store, they are even the same price, the one for home trips at rush current but the commercial doesn’t.

P.S. it is not the breaker that was tripping it is the actual GFI outlet and you have to press reset to turn it on again.

You can pretty much assume that for more than half of anything the lowe's/HD box stores do. They enlist the manufacturers to build it for less so they can sell it for less. They took a page out of the wal-mart book....unfortunately, the consumer loses. I ran into it when I bought anderson windows for my garage. Same part number, but a much cheaper built window. Fortuantely, I knew this, and it was for a garage, so I dealt with it

 

[willray]

They don't call it "Homey Cheapo" for nothing.The first big item I noticed the cheapness on some time ago was the same as JayM ...anderson windows(overpriced amyhow).