Electrical Safety and Your Tank

[WillM]

Originally Posted by Paul B

I agree with everything the original poster said.
(Master electrician 40 years, Manhattan)

Praise from Caesar....

hahah....

[Paul B]

Praise from Caesar....

No, just noise from an old retired electrician

[WillM]

Originally Posted by Paul B

No, just noise from an old retired electrician

I was referring more to the fact that your reef tank has been going almost as long as I have been alive.

[staindsoul]

^ its a compliment and insult. its a compisult.

thanks paul.

[staindsoul]

double postage

[Crackem]

I have a Neptune apex controller with a temp, ph, orp, and conductivity probe. I have all my equipment plugged into 2 different energy bars that have 8 outlets on each. These energy bars are plugged into 2 different shockbuster gfci's. All my probes are showing accurate readings except conductivity which goes from a normal reading of 35 ppt down to 11 when ever my power compacts and my 150 metal halide comes on. If I turn the lights off the reading goes back to normal. I thought this was stray voltage so I put a ground probe in the sump but nothing happened. The ground probe is plugged into one of the 3 outlets on the gfci. I'm thinking of getting a second ground probe for the tank, but at this point I don't have a clue how to fix this. I'm thinking of calling an electrician to ground the whole tank if that's even possible? Anyone have any suggestions?

[Paul B]

You don't need a second ground probe and you don't even have a problem.
a reading of 35 or even 60 is not a problem, if it were 108 or so, then thats a leak someplace and as soon as you put your hand in the tank, you would be thrown across the room so as long as that is not happening, go out to dinner and forget about it.

[staindsoul]

A second probe wouldn't change anything. The first probe in the sump grounded the whole tank.

This is just pure theory thinking out loud, It sounds like the ballasts are causing interference on the circuit. Electronic ballast drive a high frequency current, and iron core ballasts offer impedance to regulate the voltage. Etheir one could possibly interfere with that probes operation. I'm assuming that probe has to work on a voltage from a line to load and the processor determines the ppt.

Can you run a cord and run those light fixtures on a separate circuit to see if you get the same results? If you don't get the same results, you will need to separate the lights from the circuit that the aqua controller is on.

Edit:agree with Paul b. from a safety stand point your good. Your lights are jacking your probe reading, but its not a safety issue, it's a electronic issue.

Paul I believe he is referring to a salinity probe. From 35 ppt down to 11 ppt.

[Paul B]

Paul I believe he is referring to a salinity probe. From 35 ppt down to 11 ppt.

Mitchell, thank you for correcting me, I thought he was talking about stray voltage as I don't have a salinity probe or ever saw one.
One thing though, if your ground probe is in your sump, put it in your tank.
If your pumps are off, the probe may not ground anything in your tank itself. It needs a conductor to the tank which will be water and only if the pumps are running.
It's not that important but something to think about.

[staindsoul]

Originally Posted by Paul B

One thing though, if your ground probe is in your sump, put it in your tank.
If your pumps are off, the probe may not ground anything in your tank itself. It needs a conductor to the tank which will be water and only if the pumps are running.
It's not that important but something to think about.

I like it!

[Crackem]

Thx guys and yes I was referring to conductivity probe readings. I agree that my ballasts are causing interference with my conductivity probe reading. I will run an extension cord to a different outlet and test the lights. The only problem is I bought this controller to run all my equipment so I need to have it all plugged in together so I can turn equipment on or off when necessary and not just on a timer. Are there any insulation sleeves that could be used on the ballast wires to prevent this interference?

[Lavoisier]

This topic is confusing to me. I read through this post and find your thoughts persuasive but then I read through another post or article and find their arguments equally persuasive! The quality of thinking on both sides of this discussion is impressive so I am hard pressed to think one side or the other is "simply confused" about the facts--unless the "other" side does not contain any master electricians or electrical engineers.

1. First question then is do master electricians disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

2. Do electrical engineers disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

3. Finally, do master electricians disagree with electrical engineers about the need for a ground probe in a saltwater aquarium, and if so why?

[staindsoul]

Originally Posted by Crackem

Thx guys and yes I was referring to conductivity probe readings. I agree that my ballasts are causing interference with my conductivity probe reading. I will run an extension cord to a different outlet and test the lights. The only problem is I bought this controller to run all my equipment so I need to have it all plugged in together so I can turn equipment on or off when necessary and not just on a timer. Are there any insulation sleeves that could be used on the ballast wires to prevent this interference?

i see that issue of your controller being for everything. try separating the cords as much as possible, mainly the light cords. unfortunatly i dont think the cords would be close for a long enough time to cause that. outside of actually being there or replacing fixtures, i cant think of anything else to try. unless the cord test works, you could use a isolation relay and a separate circuit, but that is not a simple fix and wouldnt be cheap.

hopefully someone has run into that with those probes that can chime in. or contact the controller manufacturer. maybe they have had this happen.

[Paul B]

Are there any insulation sleeves that could be used on the ballast wires to prevent this interference?

I can't see your set up from here, (maybe if I stood on my house, but I don't think so)
There is no insulation you could put on your cords to prevent that but the ballasts themselves are putting out a lot of interference themselves so the wires are only part of the issue. I still don't see a problem. Everything electrical that uses AC power will put out some interference. It's normal. To me anyway.

1. First question then is do master electricians disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

2. Do electrical engineers disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

3. Finally, do master electricians disagree with electrical engineers about the need for a ground probe in a saltwater aquarium, and if so why?

I can't answer for anyone else and I like to stay out of grounding discussions because of just too many experts, but any body of water such as a pool, fountain, hot tub etc, by law must be grounded. They don't qualify fish tanks in that law because it would be un-inforceable inside someone's house. The ocean, lakes and rivers are already grounded so we don't have to worry about them.
The reason you don't get shocked in the ocean if you are swimming and lightning hits the water is because the ocean is grounded. A ground is there for your protection, not the fish. All it does is direct any current that accidently gets into your water to the ground rather than to you. We have all sorts of line voltage appliances in our tanks such as pumps and heaters and lights over it. All that is keeping you from dying of electricution is a sliver of plastic insulation 1/32" thick. I am even surprised that the law allows line voltage devices in a tank at all.
We usually don't find out if these devices fail until we stick our hand in the tank and get thrown across the room. Belive me, as an electrician that has happened to me dozens of times and if your heart happens to be at a certain part of it's beat cycle, you will either die, or just get shocked. It also sometimes leaves you with a sharp pain in your heart letting you know that maybe you should have gotten a ground probe. If it happens to you once, I can guarantee you will get a ground probe. I have seen a couple of people die right in front of me from electricution, it is not a painless way to die and I have also seen large wounds from electricity that take forever to heal, it is your life.
There is no down side to using a ground probe.
That is my opinion.

[staindsoul]

i cant answer those, dont know enough people for that. here is where the argument lays.

without a ground probe you will read a "voltage" between grounding and the tank. there is no current flowing. because there is no circuit. the tank has no ground or nuetral. this "voltage" is a measurement of difference of potential, not current carrying.

when you put a ground probe in the tank, now you have brought the tank to the same potential of the grounding conductor. now the tank can complete a circuit, but the "stray voltage" is now gone because your meter is not reading a potential difference.

the argument starts imo wether that voltage will carry a small current and be harmful(which it would have to be lower than 5ma to not trip a gfi), and leaving the probe out wouldnt allow any current on that "voltage". i side that "voltage" is not current carrying merely a potential measurement, and feel a ground probe should be used. otherwise you will be fully relying on the gfi to instantaneously trip when you put your hand in the tank w/o a probe.(which im a master electrician, i dont like thowing that title around because most guys that say that are just puffing themselves up and master electricans can be dumb. not a jab at paul)

i think its more hobbyists arguing than engineers or is electricians.

run a gfi at least, then decide what side of the fence youll stand on

Originally Posted by Lavoisier

This topic is confusing to me. I read through this post and find your thoughts persuasive but then I read through another post or article and find their arguments equally persuasive! The quality of thinking on both sides of this discussion is impressive so I am hard pressed to think one side or the other is "simply confused" about the facts--unless the "other" side does not contain any master electricians or electrical engineers.

1. First question then is do master electricians disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

2. Do electrical engineers disagree among one another about the need for a ground probe in a saltwater aquarium, and if so why?

3. Finally, do master electricians disagree with electrical engineers about the need for a ground probe in a saltwater aquarium, and if so why?

[Lavoisier]

Thank you both. The same information coming from two master electricians is persuasive.


Now if I can just find a couple of electrical engineers.....

[Crackem]

Originally Posted by staindsoul

i see that issue of your controller being for everything. try separating the cords as much as possible, mainly the light cords. unfortunatly i dont think the cords would be close for a long enough time to cause that. outside of actually being there or replacing fixtures, i cant think of anything else to try. unless the cord test works, you could use a isolation relay and a separate circuit, but that is not a simple fix and wouldnt be cheap.

hopefully someone has run into that with those probes that can chime in. or contact the controller manufacturer. maybe they have had this happen.

How difficult and approximately how much would it be to set up an isolation relay and a separate circuit? I live in a condo tho and I'm not sure what other info you would need to know. If its not possible to estimate it than its ok

[Paul B]

It is simple to do but I don't think it will help or do anything for you.

[staindsoul]

did you try running the lights off a seperate circuit and it work?

are you renting?

it would involve a feeder from the nearest circuit that isnt the one feeding the tank, a junction box, a cube relay, and cord from the plug that the controller runs the lights off of. since its a condo, it would suck trying that. paying someone else could start at $300 easy. i would consider switching to leds before doing all that.

but first contact neptune.

edit: also do both the halides and pcs have to come on or is it one or the other?

[Crackem]

I haven't tried yet since its very tight behind my tank and all my wires are zip tied. I tried to separate everything and then zip tied to separate ballast wires from my probe wires which are on opposite sides of the tank now. I own the condo I'm in and my last halide ballast just went out so I replaced the whole fixture ballast and bulb for 300$ about a month ago. I also have 2 power compacts and some small led strips. I had a chance to remove everything and go all LED but I chose to replace the halide instead. Oh well ... I've contacted Neptune and they want me to send the module and probe back for testing but I think it's a waste since it works fine when my lights are off Ill test the lights on another outlet as soon as I can. What's weird is that I've posted in Neptune forums to see if anyone had this same problem and no one has responded. The halides and the pcs interfere.

[sleepydoc]

Originally Posted by Lavoisier

Thank you both. The same information coming from two master electricians is persuasive.


Now if I can just find a couple of electrical engineers.....

I'm a former electrical engineer - if you find another one I'd be happy to diaggree with them!

Regarding the grounding probes, there is no solid data for or against them in terms of fish health, to my knowledge. As far as electrical safety goes, they are pretty much obviated by a GFCI outlet, the possible exception being a short with a fluorescent light fixture on the lamp side of the ballast which is effectively isolated from the main circuit.

Personal opinion: you're stupid not to have a GFCI outlet. A ground probe on top of a GFCI is probably is unnecessary, but probably won't hurt, either.

[JonnyD91]

I started a new thread on this but I figure I would ask here since you guys know whats up:

I have just experienced Stray voltage for the first time. It scared the crap out of me. I went to put my hand in the display to feed the fish and felt a tingle. The weird part was that no wired equipment goes in the display tank. Apparently it was one of my heaters in my sump that was giving off stray voltage and since water is a conductor it spread all the way to the display from the sump. Needless to say its in the garbage right now. But it was pretty scary to feel that tingle thank god i didn't get electrocuted. I have a dedicated line to the tank with an arc fault breaker and a ground fault socket. Should the GFCI have tripped in that circumstance?

EDIT: Here is a pic of my current system:
The main plug to the aqua controller which the heater was plugged into is connected to the GFCI

[sleepydoc]

Can't say for sure, but what you said is correct - salt water is a very good conductor, so your DT and sump are electrically one and the same.

Is the tank on an AFCI or GFCI, or both? Normally, a GFCI should have tripped given what you described. That is exactly what aGFCI is designed to protect against. An AFCI would not necessarily have tripped. The two are designed to protect against different hazards and are not the same.

The only thing I can't say for sure is if the controller isolates the circuit from the devices. It would be an odd design if it did, but who knows? Are You sure your GFI outlet is good? I would go to the hardware store and get a GFI outlet tester. It can check to see if your outlets are wired correctly and if the gFI outlet is working properly.

Who installed the GfI outlet? If they're not wired properly, they won't work.

[Paul B]

Should the GFCI have tripped in that circumstance?

No, a GFCI will not trip with stray voltage. Stray voltage also will not kill you or do anything else to you. If it was real voltage like if the heater wire was frayed, that is a different story and you would have gotten more than a tingle, you would have have pulled your hand out of the tank so fast you may have broken the glass. A GFCI would trip in that situation.
But if you have no ground probe in the tank the GFCI "may" not trip because you would just become the conductor but that gets confusing and that is what starts all the arguements so I will bow out now because I don't feel like argueing about it on a nice Sunday morning.

[sleepydoc]

Originally Posted by Paul B

No, a GFCI will not trip with stray voltage. Stray voltage also will not kill you or do anything else to you. If it was real voltage like if the heater wire was frayed, that is a different story and you would have gotten more than a tingle, you would have have pulled your hand out of the tank so fast you may have broken the glass. A GFCI would trip in that situation.
But if you have no ground probe in the tank the GFCI "may" not trip because you would just become the conductor but that gets confusing and that is what starts all the arguements so I will bow out now because I don't feel like argueing about it on a nice Sunday morning.

Not quite sure what you're trying to say there - I think you're tying to distinguish between 'stray' and 'real' voltage by how much current they can drive. They are both real and you can't tell the difference between them until you start drawing current.

You're correct in that a GRCI doesn't care about voltage; it works by detecting a current differential, typically at around 10-20 mA, and shuts off in a fraction of a second, meaning you typically won't feel anything before it trips. Current and voltage end up being pretty much the same thing since voltage drives current.

The 'tingle' he he felt was current running through his body and unless it came from a source outside that covered by the GFCI outlets, they should have tripped.

A ground probe in the tank will provide an alternate path to ground and may also trip a GFCI if current starts leaking through it; the GFCI doesn't care whether the current goes through the ground probe or through you as long as there's a current leak to ground.

Given what JonnyD described, I would be concerned that his GFCI is not wired properly or is malfunctioning.