Question about Faulty equipment that would leak 120v to your tank water

[greg683x]

Lets say you have tank where the fish tank power circuit is protected by a GFCI circuit breaker, but you DO NOT have a ground probe in the tank. Your heater also doesnt have a ground prong, like the many other pieces of equipment that some of us have in our tanks

If the heater youre using became defective and you have 120 volts to ground on your tank water. Would your GFCI circuit breaker trip?

[Daddi0]

Originally Posted by greg683x

Lets say you have tank where the fish tank power circuit is protected by a GFCI circuit breaker, but you DO NOT have a ground probe in the tank. Your heater also doesnt have a ground prong, like the many other pieces of equipment that some of us have in our tanks

If the heater youre using became defective and you have 120 volts to ground on your tank water. Would your GFCI circuit breaker trip?

Yes - when you put your hand in the water But in reality, the hot and neutral would probably (maybe) create a circuit underwater and cause the GFCI or circuit breaker to trip.

[alton]

Since your tank is insulated, in most cases it will wait for a grounding means. When a heater goes bad it can use the tank as resistance and draw more power until the breaker trips, if your panel is outside and in cold temps, the 20 amp breaker may not trip until 30 amps and your receptacle on the wall may catch fire. If you can add a combination Arc/GFCI breaker it will be safer than just the GFCI. They have them down to where they do not trip easily like in the past. It probably would not be a bad idea to add a hospital grade GFCI receptacle just for the heater, so not to shut down your entire tank.
I don't want to scare you but everything in my post I have witnessed

[greg683x]

well, heres the reason I post this.....

Today I had an 250w Aqueon Heater fail and leak 120volts into my sump.

I came home and saw that my heater controller was reading only a temp of 75, i have it set to 78, and it indicated the heater was on. I reached into my sump to look at the floating glass thermometer that I use to double check temp, as soon as my fingers hit the water, I got nailed. I go and grab my multimeter and check the sump water to ground and sure enough, i read 120 volts.

im really angry at that point, aside from the fact that I realize this incident could have been worse, but because I dont just have this tank protected with a GFI outlet, I went the extra mile and put in an GFI circuit breaker, to protect everything all the way back to the source.

It was at that point, I realized that my Heater does not have a ground prong and since I do not have a ground probe in the tank to compensate for equipment like this that has no ground, my GFI didnt have an opportunity to trip.

Now, I'm still scratching my head as to why the breaker didnt trip due to the neutral and hot bleeding together but since I dont know the nature of how this heater failed, I suppose its possible that just the hot lead only was exposed to water

just a beware to everybody that GFIs are not enough. If you have equipment on your tank that does not have a ground probe on your plug, then your GFI will not work in a scenario like this. i feel dumb posting this, bc I should have known that I needed a probe bc theres ungrounded equipment in the water, but its something we can all learn from.

[Matt_N]

A GFCI Receptacle does not need a ground to function correctly.

A circuit within the device compares current flow on the hot with the neutral, when they are not equal it trips(current flow is going somewhere it's not supposed to go)

So... if your water is not grounded...there is no alternate path for electrical current, GFCI won't trip.

this happens when a piece of equipment starts to fail or degrade but is not catastrophic enough to be a short circuit( a different thing entirely, and will trip the breaker, not the GFCI detection).

This is probably not that dangerous a situation because the GFCI will trip immediately when the water is grounded or some other path is provide(human hand?). I believe the GFCI will respond in 1/2 a cycle or 1/120th of a second.

Now, I don't know one thing about fish or reef keeping(I'm the new guy), but I am A Master Electrician and it seems a permanent ground in the water could shut your equipment down over a minor fault. a better strategy might be to insert a grounded conductor occasionally to seek out a ground fault, rather than deal with a GFCI trip when the tank is unattended.

[Matt_N]

As far As Greg683x situation, whatever your electrical source is, probably isn't GFCI protected, under GFCI you should never have felt a shock.

[greg683x]

would A plug tester with a gfi trip confirm it’s properly protected? Bc a plug tester works and properly trips the breaker

[alton]

Originally Posted by Matt_N

As far As Greg683x situation, whatever your electrical source is, probably isn't GFCI protected, under GFCI you should never have felt a shock.

This is wrong GFCI's do not stop you from getting shocked, they hopefully will stop the current from killing you. The following table is from Jade Learning:
1 ma (.001 amps) – Perception level and slight tingle
5 ma (.005 amps) – Shock Felt but you should be able to let go
6-30 ma (.005-.03 amps) – Pain Full Shock
50-150 ma (.05-.150 amps) – Death is Possible
1000 ma (1 amp) – Death is likely
Ma = Milli-Amps
The average GFCI Receptacle is set to trip from 4 to 6 ma so it should trip at 4 but will definitely trip at 6. Breakers and Hospital Grade GFCI's trip at 5ma (remember what was said about 5 ma)
I have always been told and believed that you don’t need a ground for a GFCI to work properly because they trip when there is an imbalance between the ungrounded and grounded circuit (hot and neutral). But with our aquariums it does not work that way because glass is a good insulator therefore there is no path for the imbalance to travel. So the leaking current and voltage just sits in our tanks until till we put our hands in it providing a grounding path. Or the piece of equipment draws enough amperage to trip the 20 amp breaker in the panel. Because the tank is insulated a faulty piece of equipment will use the water in the aquarium as resistance either cooking your tank or even exploding the equipment.

[outy]

Originally Posted by alton

I have always been told and believed that you don’t need a ground for a GFCI to work properly because they trip when there is an imbalance between the ungrounded and grounded circuit (hot and neutral)..

That's is correct.

My house has no ground wiring being 100 years old.

I have gfci anyway, and when water has been spilled it trips the plug breaker.

[greg683x]

nevermind. I figured it out

[mcgyvr]

Originally Posted by greg683x

nevermind. I figured it out

and? share for the next guy that may do the same and finds your post..

You did something stupid didn't you
At least spill the beans so we can start off Thanksgiving with a chuckle..

[alton]

A simple test: take a known power head / pump that leaks current and place in a plastic bucket with water. Plug it in to a GFCI receptacle, after the receptacle doesn't trip, drop a grounding probe and see what happens.

[greg683x]

Originally Posted by mcgyvr

and? share for the next guy that may do the same and finds your post..

You did something stupid didn't you
At least spill the beans so we can start off Thanksgiving with a chuckle..

lol, youre right, im sorry, let me explain. so my ground probes came in the mail today and I decided to recreate the scenario I had with a five gallon bucket and the old defective heater. I want to see the GFI trip, so I know Im safe if this happened in the future.

i plugged my ground probe into a gfi outlet in my bathroom, i dropped the heater in a 5gallon bucket of water along with the red lead of my meter, I plugged the heater in and the GFI still didnt trip. I put my black meter lead to ground and saw that the 120 volts was gone. As soon as I unplugged the ground probe, the 120 volts returned. I knew the reason the 120v was leaving, bc it was provided a path to ground. But I was confused as to why my GFI still didnt trip.

So I came on my computer and pulled up this thread and started to make a post and hit SUBMIT.

It was at this point that I realized that I put very warm water in the bucket and that the heater wasnt trying to kick on to heat the water. I dump the water out and refill with cold water. I repeat the experiment and the GFI plug trips. I then unplugged the ground probe, reset the GFI and plugged the Heater back in. GFI didnt trip. It just stayed there Hot in the water.

So there it is, proof of how important a ground probe is in an aquarium.

Sorry I went back and deleted the post with a nevermind, I figured it out.

[ca1ore]

So was there something observably wrong/damaged with the heater? I don't ever use the aqueon branded heaters (I'd judge them to suck) but would be interested to know what failed.

[mcgyvr]

The failure with heaters is most often at the joint between the glass body and the plastic "head" that houses the thermostat/dial,etc..
Thats why I never recommend submerging any heater beyond its glass tube even if its listed as fully submersible..
There is usually a water line mark just below the plastic cap and I abide by that at all times..

I personally have had really good luck with the "Aqueon PRO" heaters.. Not sure if yours was the "PRO" or not..

[greg683x]

Originally Posted by ca1ore

So was there something observably wrong/damaged with the heater? I don't ever use the aqueon branded heaters (I'd judge them to suck) but would be interested to know what failed.

nope cant tell by looking at it, the heater isnt even 2 years old. Whats funny is I had my hands in the water the previous afternoon cleaning the glass and changing the filter sock and everything was fine. so something failed during that 24 hour period.

during my searches for people that have dealt with this problem before, I came across a lot of talk about how Aqueon heaters commonly fail. Never found an example of them failing like this though.

Unfortunately my backup heater is a smaller 100W Aqueon that I had laying around. That seems to be doing the job for now while I wait for my replacement, I got a 250w Eheim Jager, they seem to have much better long term reviews.

[greg683x]

Originally Posted by mcgyvr

The failure with heaters is most often at the joint between the glass body and the plastic "head" that houses the thermostat/dial,etc..
Thats why I never recommend submerging any heater beyond its glass tube even if its listed as fully submersible..
There is usually a water line mark just below the plastic cap and I abide by that at all times..

I personally have had really good luck with the "Aqueon PRO" heaters.. Not sure if yours was the "PRO" or not..

it actually was in fact a Pro heater. All black, no glass.

[mcgyvr]

Originally Posted by greg683x

it actually was in fact a Pro heater. All black, no glass.

Interesting... They had been very reliable for me in the past..
Fit shappens...

I haven't been running a heater at all for the past 8 months and just pulled an old Eheim Jager out of my storage pile for the winter as I keep my house at 71F (78F normally in the spring/summer)..

[ca1ore]

Originally Posted by mcgyvr

The failure with heaters is most often at the joint between the glass body and the plastic "head" that houses the thermostat/dial,etc..
Thats why I never recommend submerging any heater beyond its glass tube even if its listed as fully submersible..
There is usually a water line mark just below the plastic cap and I abide by that at all times..

I personally have had really good luck with the "Aqueon PRO" heaters.. Not sure if yours was the "PRO" or not..

Dunno, it was a few years ago. BTW, I do the same with all my heaters, keeping the head out of the water. So unless the glass tube breaks, no way for any electricity to get into the water.

[greg683x]

Originally Posted by ca1ore

Dunno, it was a few years ago. BTW, I do the same with all my heaters, keeping the head out of the water. So unless the glass tube breaks, no way for any electricity to get into the water.

yeah i might have to start doing this. I had always kept them horizontally in the sump. maybe i can work out some kind of diagonal scenario to keep the top out, as my sump water level is much shorter than the heater