Grounding Probe

[kram138]

Ok guys. I saw this article a long time ago and have been looking for it ever since the "Power off, no tingle, power on, tingle" thread. Read it if you guys have time. I'd really like to hear some opinions on this one.

Ground Probes

[sfletch3]

Very interesting article. In the second link, grounding probes, the author does make some very true statements. The author also acknowledges that most of the detrimental scenarios are improbable situations. The bottom line, IMO, is that the use of a grounding probe in a non-GFI protected circuit can convey current in the tank and be a health and safety risk to both the fish and the aquarist. As mentioned in the article, use of a grounding probe on a GFI protected circuit will provide safety for the fish and the aquarist because when the circuit senses current on the groundside, the GFI trips open. Additionally, as described by the author, once this occurred, it is an indication of faulty equipment and needs to be address, repaired or replaced.

[Casey]

I tend to diasagree with this author.

[kram138]

Originally posted by Casey
I tend to diasagree with this author.

That's what I was thinking when I read it the first time. Why do you disagree?

[Casey]

Originally posted by kram138
That's what I was thinking when I read it the first time. Why do you disagree?

Just because I have read supposed experts saying the opposite before Fama magazine cant remember what issue though.

[sfletch3]

From an electrical standpoint, the author is technically correct. If an electrical device had a hot lead exposed to a conducting material (Saltwater), the potential is there for current flow, but without a ground source, current would not flow. The fish and aquarist would not feel anything, providing they were not grounded. By placing a grounding device into the water, current could then flow through the water and through anything connected to the water, ie..fish or aquarist. ZAP!!!!

However, even without a ground fault in place, you should still see the breaker trip. The biggest difference between the ground fault device and a circuit breaker is time. The circuit breaker relies on a bi-metallic, heat differential to trip and could take seconds to hours or days to activate depending on the breaker rating. With a GFI, the protection is electronic and trips in approximately 10 milliseconds.

Additionally, with a GFI device in the circuit, the circuit would not necessarily open unless the faulting device shorted between it's hot and ground, which could accounts for why the aquarist might fell a tingle in the water with a faulty device, even on a GFI circuit. The GFI has to sense the current to ground. When the aquarist is acting as the ground (Tingle or ZAP), the GFI wouldn't see it. By placing a grounding probe in the water and attaching it to the GFI circuit, anything in the water that faults would trip the GFI. Better over all protection for all involved.

The author does include some situations in which the GFI might not provide the protection it was designed to do and that could be harmful to our reefs, however, even the author admits that they are improbable. They would require multiple faults to occur simultaneously, at the worst possible moment in time. Looks good on paper, but just doesn't wash with reality.

[kram138]

So, let me see if understand. The best possible safety precaution for both fish and keeper is to make sure to use a GFI device in the circiut and have the grounding prob. That way you will be able to spot problems early. Am I right?

[sfletch3]

Correct! If the grounding probe is in the water, any device that is producing current into the water will trip the GFI, not just the device plugged into the GFI Circuit. For instance, let say you have a heater on a non-GFI circuit and a power head on the GFI circuit. If the heater shorts (discharges current into the water) it will travel to ground, since the ground probe is connected to the GFI circuit, that circuit will trip. You won't necessarily know which device tripped the GFI, but you will know that a problem exists. Then it is a matter of trial and error in finding the culprit. Unplug everything, reset the GFI, start plugging everything back in until the circuit trips. BINGO, time to replace that item.

[ScoobityDoobity]

What if it is the grounding probe adding the electricity to the tank? I just had to take mine out because I had a little tingle in a cut on my had, but the GFI didn't trip. I unplugged the pobe and didn't feel it anymore. Does this mean that the probe failedor my outlet is not correctly grounded?

[hayday]

so what does it mean when i put my hand in the sump and feel a neat, tingley sensation?

-hayday

[ScoobityDoobity]

It means you should do it again and enjoy the sensation!

[Demogarr]

hehehe, more members for the Tough Reefers Club (TRC)
Remember, we live for the tingle.

[JennM]

Timely thread - I just had email from a customer who's been battling HLLE with a Coral Beauty, and yesterday she mentioned that her yellow tang was looking pasty. She feeds good food, including Zoecon and Garlic, seaweed, and a variety of frozen and quality flaked foods. Her water quality is pristine - she's very conscientious. The HLLE issue came up a few months ago, she started more vitamins, and the pitting was getting better but not going away....

Yesterday she came in, mentioned the pasty looking tang, and she had recently lost a Lyretail Anthias for no apparent reason. She said yesterday that her engineer goby was looking rather pekid -- again, no problems we could think of.

This morning I got a panicked email - heniochus had died, tang was (thought to be) dead, others looking stressed.... went through all the possible causes - contamination etc., no new fish have been added in months.

I asked her to have her husband check for stray voltage. BAM! 20 volts attributed to the light timer The tang is still alive, we're hopeful that now that the source of the voltage has been fixed, that they will bounce back. She's lucky she didn't get zapped.

I mentioned a grounding probe and GFCI if she didn't already have one - this thread seems to support that

The HLLE issue had me puzzled for a long while, I've heard all kinds of conflicting notions about what causes it, and I've long since believed that any and all of the suspected causes could - voltage, diet, and water quality. Since the water quality was excellent as was the diet, I'm thinking that the HLLE was a warning sign that I missed, about the voltage.

Interestink.....

Jenn

[Alice]

I was reading a thread about GFI's the other day and one of the posters stated that if you use electronic ballast with GFI's the ballasts will continually trip the GFI. I've never had that problem; has anyone here?

[MINIATUS]

I've always used a ground probe and my light are run by electronic ballast never had one trip the GFI yet. JMHO

MINIATUS