Grounding Probe or not?

Yea but if its going to trip the main GFCI (inwall) Then it really is useless to do. Im going to have to pull from another circuit and it looks like im going to have to ground that circuit before i make any moves.

I've had them in series like that and sometimes only one trips, sometimes both.
 
<a href=showthread.php?s=&postid=12001109#post12001109 target=_blank>Originally posted</a> by Randy Holmes-Farley
Yea but if its going to trip the main GFCI (inwall) Then it really is useless to do. Im going to have to pull from another circuit and it looks like im going to have to ground that circuit before i make any moves.

I've had them in series like that and sometimes only one trips, sometimes both.
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So ground the tank, it will make you safe.
 
<a href=showthread.php?s=&postid=12001572#post12001572 target=_blank>Originally posted</a> by samtheman
So ground the tank, it will make you safe.
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Are you saying that i would not need to ground the second circuit because, as long as the tank is grounded and the pumps on the ungrounded circuit are in the tank, basically its grounded?

I have a titanium ground rod on its way, I have every intention of grounding the tank and the second circuit as needed.
 
I installed a separate 20 amp line to the wall next to my tank, with two independent GFI outlets. I have most of the equipment plugged into one GFI, and a koralia plugged into the other.

I also use a ground probe.

I'm not an electrician and not qualified to give opinions on this stuff by any means, but based on my understand and what I've read the benefit of using a probe (with a properly functioning GFI) outweighs any perceived negative, which I have never understood despite the vocal minority here that doesn't like them.
 
Mine will be here tomorrow and ill be glad to be able to put this episode behind me. I appreciate everyones thoughts and input.
 
<a href=showthread.php?s=&postid=12025551#post12025551 target=_blank>Originally posted</a> by lark
I'm not an electrician and not qualified to give opinions on this stuff by any means, but based on my understand and what I've read the benefit of using a probe (with a properly functioning GFI) outweighs any perceived negative, which I have never understood despite the vocal minority here that doesn't like them.
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It's not a dislike, it's an understanding of how GFCI outlets/breakers work - some deem the grounding probe unecessary.

One myth that seems present here - the need for more than one GFCI on a circuit. They protect ALL outlets "downstream", you only need one per circuit........but it does need to be the first outlet on the circuit (or at least the 1st from the point you wish to protect).

The second myth is that a GFCI needs a short or ground to trip - it doesn't. It measures (compares really) the inbound & outbound legs of a circuit - in the event of a mismatch it will trip. This condition IS indeed caused by a short, a ground.....but it can occur without a short.

Short version - the reason for the mismatch isn't relevant, it happened = break the circuit.

Use one or not with a GFCI, your call, your comfort level. Use a probe without a GFCI and you could very well be asking for trouble - you may be the final leg to ground (way too many variables/setups to discuss).

I am not an electrician & I am not giving advice - I am only stating a GFCI will trip without a short to ground.

<a href=showthread.php?s=&postid=11996025#post11996025 target=_blank>Originally posted</a> by Randy Holmes-Farley
I think the most common way that current flows in the water in a way that could potentially harm fish (not saying it does, however) is not "leaking" from a broken device, but induced current by the many electrical and magnetic devices we use. Whether these induced currents are increased or decreased by a ground probe, I do not know, and do not think the answer is easily worked out, but they still flow well without the tank being grounded.
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Why do you think high tension line workers "clamp on"? Birds sit on the electrical lines all the time?

Current only "flows" when it has somewhere to go, a path. Without a path I'd wager the animals aren't even aware it's in the tank - just like you underneath high tension lines.
 
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One myth that seems present here - the need for more than one GFCI on a circuit. They protect ALL outlets "downstream", you only need one per circuit........but it does need to be the first outlet on the circuit (or at least the 1st from the point you wish to protect).

Perhaps you misunderstood the point we were making. We all believe that tone GFCI on a circuit will protect everything if installed correctly. What we do not want is every single device to shut down if one has a fault. SO every device on its own GFCI prevents that. :)


The second myth is that a GFCI needs a short or ground to trip - it doesn't. It measures (compares really) the inbound & outbound legs of a circuit - in the event of a mismatch it will trip. This condition IS indeed caused by a short, a ground.....but it can occur without a short.


Perhaps you misunderstand this point as well. Sure, a GFCI will trip if there is any path for electricity to follow aside from back down the same outlet it came out of. But without something grounding the tank, there may be no other path, and so current may not flow until that other path is put into place. Often that new path will be the aquarist, perhaps with one hand in the tank and a second on his light to balance as he cleans the tank. The GFCI may then trip before he gets a lethal dose of electricity.. But I'd want to know if such a scenario was in place before I completed the loop.

Use one or not with a GFCI, your call, your comfort level. Use a probe without a GFCI and you could very well be asking for trouble - you may be the final leg to ground (way too many variables/setups to discuss).

That is a point we agree on, and I do not think anyone here recommended aground with the tank not on a GFCI. :)


I am only stating a GFCI will trip without a short to ground.

Where do you propose the electricity goes? If you mean that another device may be grounded, then yes, that device grounds the tank. Or in some cases it will actually leak into the actual ground under the tank, like a basement floor. But often there is no adequate path to ground in an aquarium to trip a GFCI.

Why do you think high tension line workers "clamp on"? Birds sit on the electrical lines all the time?

Current only "flows" when it has somewhere to go, a path. Without a path I'd wager the animals aren't even aware it's in the tank - just like you underneath high tension lines.

Do you not understand what induced current are? You believe they do not exist? Induced currents are well understood. I don't claim they will kill a human. But many marine organisms are unusually sensitive to electrical issues in the water around them. Will that hurt them? I do not know, as I stated above. But your assertion that they are harmless seems rather unsubstantiated.
 
Well put Randy, I think you did a great job articulating and clarifying some very valid points of confusion. I totally agree on all points.

The bird on a wire scenario is not pertinent; maybe if you could put the bird in the wire we would have a closer analogy. The real point is electricity will always take the path of least resistance. What we are talking about is creating a different path through an animal or person. Now, if that same bird was on that same wire, and moved close to, or, touched the tower (a path to ground), it would be not only be dead but most likely vaporized.

I also agree that no GFCI and a ground probe is a very debatable situation, but firmly believe you shouldn’t be without the GFCI in the first place.
 
Interesting stuff. Back when I did cichlids I followed a few threads on this topic. When you asked the ocupation and if they used a ground the answers I feel was very revealing.

Everyone always agrees, always use GFCI outlets.

Any electrical engineer who worked with high voltage regularly flat-out without hesitation said they would not use a ground probe.
 
<a href=showthread.php?s=&postid=12000406#post12000406 target=_blank>Originally posted</a> by mixed_reefer
so i can take a 3 pronged ext cord and wire it into a gfci outlet and box and then plug it into another gfci? I want my pumps separate from the rest of the tanks electrical but i want it all on gfci's.
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No, they will not work connected in that manner. You can not daisy chain GFCIs from LOAD to LINE or plug one GFCI into another.

You must wire them in parallel. That is, each GFCI receptacle should be fed directly from the hot and neutral feed.
 
FWIW:

Current DOES flow through the bird. The wire he stands on has a known resistance, voltage and current. The birds body is a conductor with a known resistance between his feet. When the bird stands on an energized wire, he becomes a parallel resistor with the portion of the line he stands on. The current is very small but it does exist because his two feet are separated by a few inches and therefore at differing points of potential on the wire (due to its own resistance).

The situation is more complex in a fish tank where the conductor surrounds the animal, but like the bird-on-a-wire, current can and will flow through the fish from one point of potential to another. If the fish is in that path of current, a portion of it will flow through the fish.

We know that many marine creatures are hyper sensitive to electrical fields...

Like Randy, I don't have the answers and I am not sure where I stand on ground probes from the perspective of the animals and electric fields or currents. I do however know that a ground probe is an enhancement to the GFCI protection that SHOULD be on every fish tank.

I do not use a ground probe, but have made that choice based on a firm grasp of the electrical realities on both sides of the issue.

Also FWIW, the lineman clamps onto the wire so that he does not get an ARC from the wire to his body. His body (like the birds) has resistance. The surrounding wire has LESS resistance. It is therefore more likely for a local object to then arc directly from the wire, NOT through the lineman. What object would that be? Anything, including the bucket or helicopter that places him on the wire.
 
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Salt water is conductive, pure h2o and I mean pure no TDS is not, it can as is used as an insulator in some comercial pump motors as a coolent, so the salt water flow from the first floor to the sump/fuge is a conductor, just like a copper wire. If you look at your circuit breaker box most if in a basement are grounded to a water pipe, it is the ground for it, because the piping is under ground and our planet Earth is the ground.
 
Ok so it doesn't matter where the ground is then. Id rather mine be in my sump (Need to buy one still) What is the best kind of ground the only ones I have seen are the plug in the wall type.
 
If you have a basement and your electric box is grounded that way, and have a water meter where your water main comes in you will see a copper cable strap connected to each side of the piping around the meter because the meter will not let the ground become completed, so the have to "bypass" the meter this way.
 
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