Ok I should have my grounding probe in about 2 days...My question is where do you guys mount it? I would think in the main tank is more important...If i put it in the sump/refugium will it still remove the stray voltage in the main tank? do you guys use 2 one in the sump and one in the tank? Im much more concerned about stray voltage in the Tank than the sump!...This is where the PH's are too! all input appreciated

http://www.reefland.com/ubb/Forum14/HTML/000476.html#4

SPASSE, an EE, recommended to ground the sump/refugium and tank individually.

Gia [img]/ubb/smile.gif[/img]

Hi,

I have a AAS in Electrical Eng. and definatly second Baywatch Babes reply.

[img]/ubb/fish.gif[/img]

I am a Mechanical Engineer who aced all my EE classes. I recently researched this extensively, in fact the thread is still active: ("Shocking!!!!!! Electrical question") http://www.reefland.com/ubb/Forum14/HTML/000803.html

I am still waiting for confirmation from the people who have demonstrated expertise on this subject (see the threads I referenced), but I feel my reasoning is sound and I know it is based on a lot of previous discussion.

I have learned a lot from this and other reef boards and want to make a contribution by settling this issue in the form of established guidelines such as I presented (as a proposed set of guidelines).

I don't think a simple (and complete) answer will ever be possible for this question - it depends on your circumstances, and assumptions about such are dangerous!!!

For example:
Use of a grounding probe without GFCI could get someone killed (depending on circumstances).
Adding a grounding probe can cause more harm than good to your livestock (depending on circumstances).

BTW, I do not disagree with the above replies (depending on circumstances) ...

SPASSE: have you read my long post as referenced above? What do you think? I do have a couple more minor questions on the issue ...

Thanks,
Bob

Hi,

Here is how to test your AC outlets.
Using a voltmeter measure the voltage between the hot and neutral, should be appr. 120 VAC. Measure voltage between hot and ground, should be appr. 120 VAC. Measure the voltage bteween neutral and ground, should be less than 3 VAC. The hot is above the ground hole to the right. The neutral is above the ground and to the left. Ground is the hole under the hot and neutral contacts. If there is more than 3 VAC between neutral and ground you probably do not have a ground on that circuit.

The reason I suggest 2 probes is that there are equipment in the sump and the display tank. Granted that you have a proper ground on the circuit you power your equipment from it is safest (for your livestock) to have probes located near the equipment you want protection from.

As for the induced voltages the biggest culprit would be halide ballasts. They have big transformers to step up voltages. This I don't think would be too bad if your ballast is located somewhere else besides under your hood. I think most are located in the stand.

Well my program mang. ( who holds three masters and a phd ) just came by and saw me on the net so I showed him Reefland and he informed me that he worked at SCRIPT (sp?) the second biggest ocianic (sp?) in the country for 10 years. He stated they used grounding probes in all there tanks along with lightning rods. I asked him what for besides what I have already wrote and he said (which I am embarrassed for not thinking of) that in dry conditions your glass can act as a diaelectric and in conjunction with the sea water inside you can have capacitor.(charged too.)
I am now out of time so I will go. I think eveyone should check you AC outlets because improper wiring is dangerous to your computers and other electronics also.
[img]/ubb/fish.gif[/img]

Soundman, that last point is one of the issues I was still wondering about; can the tank act as a capacitor?

Ok guys now your scaring me! I just wanted to know what to do....usually i get the majority of responses to point me in one direction....now you all you guys seem to have knowledge in this area but there seems to be a conflict of interest.....I dont want this electrical engineer mumbo jumbo....Give it to me in Laymens Terms PLEZ.....I mean should I do away with the GFCI and go w/just the ground probes so i wont get shocked AGAIN.....the reason i made this post and did not post in the other one was because you guyz where getting way TOO complex for me. I have a freind who is a handy man and knows alot about electricity, should I just have him come over and take a look at my setup and have him help me? he is my fishing buddy so I know he wont charge me, cept for parts....I was really trying to avoid this cuz he is always buzy at work and he doesnt like mixing work w/pleasure....I just hate to put him on the spot.

scubadude,
Ohmygosh, my fault, I'm sorry ...

Use the GFCI. Period. Please.

You got shocked? Please describe what happened ...

Use the grounding probe. Put it next to a powerhead if you can. Connect it to the ground on your powerstrip or at the wall outlet. (Soundman described which one is the ground)

If the GFCI trips off, you almost certainly have a faulty piece of equipment that needs to be identified and fixed.

If your fishin buddy comes by for a beer sometime and has his multimeter with him, have him check if your neutral is at zero voltage. This will give us some more information.

Sorry for the confusion,
Bob

scubadude,
Ohmygosh, my fault, I'm sorry ...
Use the GFCI. Period. Please.

You got shocked? Please describe what happened ...

Lol...there was a tint of sarcasm in my previous post above...but I am concerned...I just got a little confused thats all...I dont want to think im doing the right thing by putting a ground probe(or two) and 2 GFCI outlets, only to find out that Im gonna get shocked again....The other post ("Shocking!!!!!! Electrical question") Explains when I got shocked....I was following up with you guys on this post and I posted in there it explains what happend there...but its no big deal now....well I mean I removed the PH's that caused the problem and everyones ok (my corals...me too [img]/ubb/tongue.gif[/img]) I think I will have my buddy come over and let him do it....I will probably let him see this post too, and the other one. Im sure he will know exactly what you guys are talking about. Im sorry if I came off strong

scubadude, LOL, that's what I thought at first but then I got paranoid ... [img]/ubb/biggrin.gif[/img] pretty funny, actually .... [img]/ubb/biggrin.gif[/img]

Hi All,

Well I could get in to a detailed discussion the theoretically possible current flow paths, induced currents, differential voltages, circulating current paths, etc, in all most all cases, in systems with a sump, two (or more) ground probes and a GFI is the safest course. Most of the catastrophic “meltdowns” involving for example the RIO pumps, would have been avoided if the systems in question had utilized a combination of ground probes and GFI’s.

Also whether the neutral wire is at zero volts relative to ground is irrelevant, indeed it seldom is. This is because current flow between hot and neutral (the normal current path) will cause neutral to be some level above earth ground potential. This amount is dependent on the circuit load and the resistance of the copper wire and the various outlet connections involved. The issue is that the ground is not substantially above true earth ground in potential. This should not be the case as with the exception of a ground fault, there should be little if any current flow through the ground path of a circuit.

On a personal note, I have observed first hand the positive effects of grounding a system of the physiological behaviors of fish. Grounding a tank caused a marked “calming” effect. Glass is an excellent insulator, and ungrounded systems have the potential of achieving a static potential of many thousands of volts above earth ground.

Finally, consider this, the ocean is by definition “grounded”

Regards,

Scott

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The definition of an expert is a washed-up drip under pressure.
You can see my reeftank at http://www.homestead.com/spasse/