GFI & storms

[StirCrazy]

Originally Posted by Doug

In all my years of using GFI ,s on my tanks, never had this problem before. Apparently we are in the middle of monsoon season here. During one of the storms today, lightning I guess, created a brief power down. Computer, aquarium,etc. It was only like a sec.

Power back but I noticed my sump, return and skimmer not restarting. MP 20,s running, as they are on another GFI/arc fault circuit. I find the GFI tripped on the above mentioned circuit. Reset it and everythings fine.

However, of course that scenario is no good if no body around to reset. So I ask. What the &&&^%$. Does this mean I have a problem with that wall GFI I installed, as opposed to the GFI/arc fault in the breaker panel?

I was thinking about this and let me see if I have this right. you have a arc fault breaker in the power pannel then you put a GFI plugin which you plug your stuff into. right?

If this is the case it will keep randomly tripping, as the arc fault and the gfi with kinda get confused and argue with each other. this was a common problem when they introduced arc fault to places that also had a requirment for GFI. take a dinning room for eg, commonly they were run on the same circut as kitchens and because there were gfi instaled on that circut by the sink when they installed the arc breaker in the pannel it would cause nusence tripping. so now they have to run a seperat arc fault circut for the dinning room.

I did some more reading there is a combo GFIC/AFIC breaker made by cuttler hammer, but they are expensive, and a waist of money for most aplications.

Steve

[Doug]

I have a separate GFCI which was installed just for my tank, with a spearate 15amp breaker in the panel. I run my controller on it, which runs the lights, heater, etc.

My place also has GFCI/AFI, in some rooms, the room my tank is in being one. Those breakers are code here in new homes for some rooms, I think bedrooms. My tank/office is in what would have been a small 3rd bedroom.

The arc faults are very sensitive, and I would not run all my equipment on them, plus as mentioned they dont fire halides.



I copied that from another thread Steve. I will be darned if I know where the pic of it is.

They are not the same circuit. All the bedrooms and bathrooms in my house have GFI/arc fault breakers in the panel. The GFI I,m having problems with is a completely separate circuit, installed just for the tank. It has its own regular 15 amp breaker.

Also as I said, part of my tank runs on the standard GFI circuit and part runs on the GFI/arc fault circuit, which are completely different plug ins.

[Lampshade]

Well... there's another option too. GFCI's trip based on detecting trickle currents. They operate in 20-40 milliseconds. That is EXTREAMLY fast, 1 cycle is 16ms. A typical distribution circuit breaker operates in 2-20 cycles(depending on magnitude of the fault). and faults far down a line are generally co-ordinated to clear a fuse or a recloser first, which may take 2-3 cycles. This is still longer than the GFCI.

Pretty much, you may have had phase to ground fault in your area, raising the ground potential enough for your GFCI to pick it up. the GFCI will operate before the fault is cleared by your power company's protection.

[Doug]

Alrighty. Took a couple quick pics of them. These are of course horizontal in the box.

I thought they were standard now, but have a hard time making believers.

[Doug]

Originally Posted by Lampshade

Well... there's another option too. GFCI's trip based on detecting trickle currents. They operate in 20-40 milliseconds. That is EXTREAMLY fast, 1 cycle is 16ms. A typical distribution circuit breaker operates in 2-20 cycles(depending on magnitude of the fault). and faults far down a line are generally co-ordinated to clear a fuse or a recloser first, which may take 2-3 cycles. This is still longer than the GFCI.

Pretty much, you may have had phase to ground fault in your area, raising the ground potential enough for your GFCI to pick it up. the GFCI will operate before the fault is cleared by your power company's protection.

Thats sounds like a very good explanation. Of course no idea if thats the case or not. If I may add I had several gfi,s wired into my stand for my 90g at this residence and several of the same at my previous residence. Had power blurps or complete failures in both situations and never had a gfi not restart when power came back.

[Lampshade]

Since your power was turned back on within a second or 2, it was most likly an automatic reclose that brought it back, automatic recloses are usually in place to "pop" a tree off a line, and they work. If the tree was close by your house, it may have been able to show up as ground current in your house for only a the 1-2 cycles before the fault was cleared off the power line. Usually doesn't happen since there's usually many houses fed by the same circuit, and odd's of the tree being close to enough to yours is slim.

[Lampshade]

may still be a bad GFCI, they do need to be replaced sometimes, that's jsut another option. If it's usually fine and just one isolated incident, could be something external, like the power outage location. If it keeps happening then most defintily replace it, In Manitoba i'm sure you get to test it frequently enough :P. And since you're in Manitoba could actually have been a lighting hit on the distribution system, rare out here, but more common in the prairies. That would defintily raise the ground potential.

[Lampshade]

And... just to overkill this more... Could also have been a surge protector plugged into the GFCI, they shunt excess voltage to ground, which will trip a GFCI. Lightning strike would be a surge, and sent to ground by your surge protector, through your GFCI. Good surge protector's are almost instant, something like 1/100 micorseconds.

[westom]

Originally Posted by Doug

I thought they were standard now, but have a hard time making believers.

GFCIs are not used on refrigerators for same reasons you have suffered.

GFCIs can be surge damaged if proper 'whole house' protection is not installed. So newer GFCIs will trip open on power loss. And will not reset if surge damaged. That is a problem for you.

So many have posted myths. For example, any ground fault before that GFCI is completely irrelevant. The only relevant ground fault is after the GFCI. AFGIs and GFCIs do not 'fight' - another myth based in not understanding what these devices do. GFCIs do nothing for surges - for so many obvious reasons.

A GFCI measures an electromagnetic field around both wires. Obviously, this causes no power changed or problems. If those fields are not same, then a GFCI opens. IOW if current after the GFCI finds some other path to earth, then GFCI trips.

This is considered a major human safety problem for refrigerators. Therefore GFCIs are exempted on appliances that cause safety problems when tripped.

[Doug]

Thanks for the input guys. Just trying to decide on what option to try so that when away and power flickers, I still have most things running. Likely best to only runs lights on that circuit when away and the rest on the house gfi circuit.

So then Westom, why does the other GFCI/AFCI not trip under the same circumstance? Is there a difference between the ones we install and my panel breakers?

Also Steve. Never heard from you since posting pics of the GFCI/AFCI. Dont you guys use them in Alberta or BC ?