Do GFIs trip easy?

[guntercb]

Hello,

I just had some work done on my house and I had the electrician replace the electric outlet that my fish tank connects to with a GFI outlet; however, he tells me that I do not want a fish tank hooked to a GFI because with the pumps and equipment it will keep tripping and become a big pain. Now lots of people recommend GFIs for safety. Is it true that the GFI will keep tripping and create a problem? Or is my electrician just feeding me a line?

Thanks,
Chris

[theop]

I think they are a good thing. I never had mine trip in about 1 year on my 37 gal reef.

I had the following plugged in: 3 fluro light hoods, 3 pumps, 1 heater, canopy fan (DC adaptor). I didn't have a grounding probe, so I don't know if this makes a difference in tripping them or not.

[guntercb]

Theop,

Thanks for your input. I requested a GFI up front and they quoted me a price. It was not installed and I think they are really just giving me a line so they would not have to replace it. But I now have a GFI so I guess I may find out if it trips easy or not.

Anyone else?

Thanks,
Chris

[AZDesertRat]

If it trips there is a reason and its just doing its job.

[moonman]

Hi,

I dont remember which one I had previously, but it kept tripping when my metal halides would turn on. I switched to a leviton brand, and I've had no problems since...

[clsanchez77]

I agree with AZDesertRat. They are also known to become 'sensitive' and can in fact trip falsley, but I have never had it happen to me.

[BeanAnimal]

GFCIs can nuisance trip due to the complex way that some ballasts and motors use electricity. Most aquarium pumps and ballasts should be fine. LARGE motors or ballasts can prose a nuisance tripping problem. If nuisance tripping is a problem, you can try a different brand of GFCI or moving the devices to seperate GFCIs. MOst of the newer generation of GFCIs have better comparator logic and nuisance trip less.

Most electricians and DIYers will tell you that you can NOT put more than one GFCI on a circuit, that is 100% nonsense.

If you wire the GFCIs in parallel then each will operate independently on the same branch circuit. In this way you can seperate your PUMPS, HEATERS, LIGHTS onto different GFCIs even though they are onteh same branch circuit. The will keep a nusiance (or real) trip from bringing down the entire tank. Instead only the faulty (or nuisance) device will go offline.

[Freed]

If it trips "falsely" you have a faulty GFCI and you need to replace it. They don't become sensitive for any other reason than they are bad.

[BeanAnimal]

Freed that is partially incorrect. Depending on the comparator, they can be "fooled" by a complex load. First generation GFIs were horrible with anything other than a straight resistive load. Motors and Ballasts provide a complex power usage signature that has significant capacitance and back EMF. The GFI can read this as a ground fualt when in fact there is none. The new generation of GFCIs is much better at reading the true nature of a fault compared to a complex motor or ballast load.

GFCIs are also VERY prone to nuisance tripping in humid locations....Add a little bit of salt and the situation becomes worse. Again, the newer generation of devices is getting better.

AFCIs are even worse when it comes to complex loads :)

[Mr.Nudibranch]

I would cross that road when you get there;) because it sounds like it just depends on the unit or brand it self.

[clsanchez77]

Most electricians and DIYers will tell you that you can NOT put more than one GFCI on a circuit, that is 100% nonsense.

I have actually never heard that before and it is total nonsense. I have two on one bathroom circuit, three on my kitchen circuit and four on my aquarium circuit.

Chris

[BeanAnimal]

Yup... putting them in series (LOAD to LINE) can cause some unwanted effects... but parallel is just fine :)

[SteveOhh]

<a href=showthread.php?s=&postid=7512231#post7512231 target=_blank>Originally posted</a> by clsanchez77
I have actually never heard that before and it is total nonsense. I have two on one bathroom circuit, three on my kitchen circuit and four on my aquarium circuit.

Chris

Why?????

If they are wired correctly, A GFCI will protect all the outlets after the GFCI. Sounds like someone wasted money on $10 outlets when they could have spent .75 for each outlet.

[Arik]

I have had horrible luck with the plug in units. Two of them failed in a couple of months, where they would trip for no reason and have trouble resetting. I've never had any problems with ones I've hardwired into the wall.

[BeanAnimal]

WHY????

Steve the reasoning is VERY simple...

If you don't want a fault to trip everything on the branch circuit, but still want that equipment protected, then you can use multiple GFIs. This is very relavant in our hobby. You don't want a faulty ballast to shut down your return pump, which is exactly what would happen if all of your aquarium devices were downstream of a single GFCI.

Just the same, I don't want the faulting Christmas lights on the front porch causing the bathroom outlets to go dead.

Most folks don't understand that you can put more than 1 GFCI on a circuit. They are usually told not to place more than 1 GFCI on a circuit. Most advice givers usually assume that they will be wired LOAD to LINE (in series). Most advice givers never stop to think that wiring them in parallel will work just fine and enable granularity of protection on the same branch circuit.

Arik,

It could be a moisture problem (or salt creep). It could also be a quality problem... a lot of stuff sold these days is outright junk.
Bean

[guntercb]

BeanAnimal,

Thanks for all of your valuable information.

My electrician and GC were humming and hawing talking about how you don't want GFI were pumps and compessors are running. I think they have had bad experience with swimming pool pumps on them. And maybe they think my little tank pump will have the same issue. Anyway I have my GFI on the outlet now. Unforetunetly, I just moved in and have lots of house stuff to attend to, but soon I will set up my tank and test the GFI.

Thanks again.

Cheers,
Chris

[want2reef]

I have been having problems with my GFCI tripping after I switched from SE's to DE's. JFYI

[Arik]

I know why I had problems with the plugin units----they're junk. They were never near any sort of moisture.

[clsanchez77]

If they are wired correctly, A GFCI will protect all the outlets after the GFCI. Sounds like someone wasted money on $10 outlets when they could have spent .75 for each outlet.

Exactly what BeanAnimal said. It is not an issue of wiring correctly or wasting money. I rather spend the extra money so a faulty toaster in the kitchen does knock out the cabinet lighting or the cracked heater does shut down my tanks entire operation. Have an open mind and don't be so critical of others who have different approaches.

I have been having problems with my GFCI tripping after I switched from SE's to DE's. JFYI

I have two 150W DE's on one of my GFCI's and it has not tripped yet. I wonder if one of your ballasts is leaking current to the ground. Could also be a GFCI quality issue as mentioned above.

[TheGriffin]

I assume that GFCI's and AFCI's can be used on the same line right? (as in a AFCI breaker in the breaker box and GFCI's outlets) My plan was to run 3 GFCI outlets for the tank with the Arc fault breaker. Since I'm runing T5's I shouldn't have issues with halides trippping the AFCI like some people have reported.

[Arik]

Just a note, I have 2 x 250w DE on a single GFCI and have never had a nuisance trip (on the hardwired type). Check the ground on your setup.

[BeanAnimal]

Griffin...

A GFCI trips at 6 mA of imbalance between hot and neutral. That is it's only job.

An AFCI trips when it senses "arcing" which is a complex pattern. However an AFCI will also trip at 30 mA imbalance (acting as a GFCI).

So with an AFCI you get a GFCI (albiet a bit less sensative).

There are combined AFCI/GFCI breakers available also that have 6 ma fault sensativity.

All of that said.... AFCIs are a pain in the ***. Some silly statistic showed that most bedroom electricial fires are due to ARCING from improplerly plugged in devices and faulty electric blankets and such. To make a long story short, most people laugh at the statistics... but thats another story.

The problem with the AFCIs is they are VERY VERY VERY prone to false tripping. That is why they were not mandated for use in the entire house... You rarely run a complex load in the bedroom (other than a vacuum cleaner, that will cause the AFCI to trip).

They are getting better, but they still suck.

NOW lets talk about why you would even want one on your tank? ARCING can be caused by salt creep and water spills. However good wiring practices and keeping power strips out of the stand will go a long way to preventing problems. If you use quality equipment with grounded plugs, most arcs will trip a GFCI before a fire starts.

Most people want to use an AFCI to stop fires caused by arcing fluorescent tubes. The problem is that the ARC is on the wrong side of the ballast and the AFCI will not see it in most cases.

Bean

[clsanchez77]

BeanAnimal...well put!

BTW, I have heard of AFCI becoming required on outdoor Hot Tup and Pool installations (and similar outdoor water installations, like ponds) where lights are submerged under water, but I suspect it is speculation. Like you said, it is not accomplishing anything GFCI will not with a good ground.

Chris

[revance]

I agree with most everything BeanAnimal has said...

Although I have never heard anyone say you can't put multiple GFCIs on a circuit. Some people look at you strange when you do it because they don't realize you want things to trip seperately, but I have never heard that. My guess is someone misunderstood that and turned it into "you can't" rather than "you don't need to".

I don't think the electrician was trying to pull one over you. It is their general practice to not put anything on a GFCI that cannot go without power. Hence you will not find an electrician telling you to put your freezer on a GFCI.

I also agree that AFCIs totally suck *ss!!! Stupid new code.