GFCI Outlet poll

Where are you on Ground Fault Circuit Interrupter outlets for your power supply?


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SMSREEF

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I was running my nano without GFI, but never felt secure. I’m upgrading to a 60 gallon with sump and there is just so much more running that I wanted to be safe.

I put in a couple GFI’s that have a really cool feature. They have an alarm that goes off when tripped. I won’t get an alert to phone, but as long as Someone’s home, they will know it was tripped.

I also have a battery operated air pump set up for tank and sump in case of power outage.
 

zalick

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When a GFCI trips it has no effect on the mechanical ground connection(third prong) so a ground probe is still functional regardless.

Right. Brain fart by me.

I'm still confused as to the benefit of a probe connected to a GFCI?

Assume fault situation #1. Pump on GFCI leaks current in water. Probe returns leaked current to ground. GFCI trips.

Fault #2. Pump on non-gfci leaks current. Probe returns current forever. Dangerous right?

Fault #3: pump on non GFCI leaks current. No probe. Hand in tank and other hand grounded. You become ground. Dangerous.

I'm missing something in the probe setup it seems. Thanks for the information!
 

fermentedhiker

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Right. Brain fart by me.

I'm still confused as to the benefit of a probe connected to a GFCI?

Assume fault situation #1. Pump on GFCI leaks current in water. Probe returns leaked current to ground. GFCI trips.

Fault #2. Pump on non-gfci leaks current. Probe returns current forever. Dangerous right?

Fault #3: pump on non GFCI leaks current. No probe. Hand in tank and other hand grounded. You become ground. Dangerous.

I'm missing something in the probe setup it seems. Thanks for the information!
The point of a probe for a GFCI is our tanks are essentially insulated buckets of water. So a device like a heater can have a fault and not trip a GFCI because of how GFCIs work. They function by detecting a difference between the amount of current flowing on the hot and neutral conductors. If there is no path to ground the electricity can flow in the tank water but it completes the original circuit because there is no alternate path so the GFCI thinks everything is fine. With a ground probe there is an alternate path so some of the electricity gets back over it giving the GFCI something to detect so that it can trip.
 

fermentedhiker

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Right. Brain fart by me.

I'm still confused as to the benefit of a probe connected to a GFCI?

Assume fault situation #1. Pump on GFCI leaks current in water. Probe returns leaked current to ground. GFCI trips.

Fault #2. Pump on non-gfci leaks current. Probe returns current forever. Dangerous right?

Fault #3: pump on non GFCI leaks current. No probe. Hand in tank and other hand grounded. You become ground. Dangerous.

I'm missing something in the probe setup it seems. Thanks for the information!
I may have misunderstood your question. Your three scenarios are basically correct. The ground probe will allow the GFCI to trip at the first occurrence of the fault where without one it might not trip until you provide a path via your body. Less optimal for sure. Not necessarily unsafe as GFCI trip incredibly fast so you wouldn't even feel anything before it did, but I'd personally rather not be the path :)
 

zalick

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The point of a probe for a GFCI is our tanks are essentially insulated buckets of water. So a device like a heater can have a fault and not trip a GFCI because of how GFCIs work. They function by detecting a difference between the amount of current flowing on the hot and neutral conductors. If there is no path to ground the electricity can flow in the tank water but it completes the original circuit because there is no alternate path so the GFCI thinks everything is fine. With a ground probe there is an alternate path so some of the electricity gets back over it giving the GFCI something to detect so that it can trip.

Thanks. I didn't realize leaked current in the tank would still return on the same neutral.

So essentially the probe is somewhat necessary, in a leaked current situation, to trip the GFCI? And without the probe, you might be the ground that trips it?
 

fermentedhiker

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Thanks. I didn't realize leaked current in the tank would still return on the same neutral.

So essentially the probe is somewhat necessary, in a leaked current situation, to trip the GFCI? And without the probe, you might be the ground that trips it?
ignoring other possible grounding sources in your tank(such as possibly some titanium heaters) yes.
 

piranhaman00

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Very informative thread! Thanks everyone for the contributions :)
 

donfish2

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If i did not have my tanks set up with GFCI receptacles, I would be dead, period. Water seems to find a way to all exposed receptacles, power cords, power strips, etc. I just got zapped resetting the GFCI, the other day, when the power went out and came back on. When working on aquariums try and where sneakers to keep yourself somewhat insulated from stray power, it may keep you from being killed.
 

Brew12

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Thanks Brew!

So the titanium heater will work as a ground probe at all times even though it is connected to a controller which cuts its power?

If I understand correctly, the stray voltage will run through the titanium heater and back through the gfci wall outlet or any outlet and then to the ground at the house panel (where all grounds lead to). This in turn will set off the gfci outlet associated with the tank?

So whatever gfci outlet that the device with stray voltage is plugged into will be the one that trips, correct?

Thanks for all your help!
Not all titanium heaters will, but most of them do. If it doesn't have three prongs on the plug or if it has a built in controller it can be questionable and should be checked with a meter.

Oddly enough, GFCI's don't look at ground at all. It looks at current through the hot leg and compares it to current through the neutral leg. If they don't match, it assumes the missing current is going where it doesn't belong (to ground) and trips.
 

Brew12

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Thanks. I have 5 finnex non-thermostat grounded heaters. So these will also act as a ground probe?
Yup, if its the same model I have they act as ground probes.

If I have the probe on an isolated GFCI, separate circuit from the equipment, and it trips, haven't I essentially lost the protection of the probe with potential faults on the equipment still hazardous?( Assuming they aren't GFCI protected)
The ground slot on any controlled outlet should never open even when the outlet is off. Even power strip grounds should be fine with the switch turned off.
 

fermentedhiker

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Yup, if its the same model I have they act as ground probes.


The ground slot on any controlled outlet should never open even when the outlet is off. Even power strip grounds should be fine with the switch turned off.
not sure why that quoted me as it wasn't my post. I think it showed up as a bad edit from a reply I was attempting while also talking on the phone :/
 

Oliver d

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My system runs through a Earth leakage relay that's what GfCI are called here.I also have a ground fault prope connect.the only thing on the tank that is still connected to the 220 volt supply is my thermostat everything else is 12/24 volt with the power sources sitting in a other room.
 

Phil D.

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Hi All, nice discussion. As an Electronics Tech I installed a GFCI with alarm on my tank, (Home Depot $30). You must remember it's NOT the voltage that kills you, it's the current, (100mA). So everything that we use in our tanks has the capability to put you 6ft under. So, I highly recommend installing a GFCI.
 

zalick

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Hi All, nice discussion. As an Electronics Tech I installed a GFCI with alarm on my tank, (Home Depot $30). You must remember it's NOT the voltage that kills you, it's the current, (100mA). So everything that we use in our tanks has the capability to put you 6ft under. So, I highly recommend installing a GFCI.
The newer GFCI with alarm are great. :)
 

Mrreefercanada

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Never had one for 20 years! This year I had a heater short out in my sump and the safety didn't work! I found out the hard way by putting my hand in the sump water during regular maintenance !? Not cool and very dangerous!
 

bar|none

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I use an external one from North Shore Safety.


They have auto reset versions that will attempt automatically to reset a tripped circuit for a period, which I think is kind of awesome. EDIT [ another reefer clarified that I misunderstood this feature, see response later in thread.]

So far reliable.
 
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MarcF

MarcF

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I read all the posts. I googled.
I'm putting in the GFCI (with alarm if available).
Now, here's all the information that I've picked up, and where my level of understanding is at the moment - which is much less than the understanding of many of the members. So I'm a layman, setting up an aquarium. I'm not setting up a power plant. I'm hoping my level of knowledge at this point, is sufficient to keep both myself, family, and finny friends from being fried.

Here's what I now believe I understand, from reading all the posts and also googling up a few articles:
Ground probe without GFCI is bad (according to article) because it provides a path for current, which is what you don't want. Without a path, current goes no place. True you're preventing yourself from getting a shock when you put your hand int the tank. But Ground probe value is debatable. On the other hand, there's no debating the value of the GFCI outlet. I see now there are adapters for about $25 you can plug into existing. I just called a local electrician and will get a quote on installing a regular one. I could probably do it myself but let's see what she will charge.

People have recommended having 2 independent GFCI outlets. I can see the advantage, but I don't think I'm going that far. People have recommended plugging everything into the GFCI but many say, at least the return pump should be in a regular outlet in case of tripping. Then others have commented that faulty tripping almost is never an issue any longer. And there are alarms.

This is a complicated hobby. When experts disagree, it's not easy to make decisions, especially when you're not an expert yourself. But as a home hobbyist, I've come to the following plan here:
-have a GFCI installed or install it myself
-forget the probe (I'll check my heater though, as maybe it functions as a probe - just checked, and no it doesn't :()
-plug everything into the GFCI except the return pump, which I'll plug into a regular outlet, but watch it like a hawk and make sure it's well away from wetness. That part may prove tricky. Where do people position their return pump, usually?
-make sure there are drip loops wherever needed

Am I forgetting anything, or have anything wrong?
Feel free to comment. Thanks for all the answers. It's gotten me to here.
 
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