Stray voltage Please help!

[jlnielsen13]

Hey CMAS,

I posted this in a main forum but thought I would try local for help as well-

First the system is a 90 gallon mixed reef that has been set up for 6 years:
Here is a pic so you guys can picture the tank ( I like visuals when solving a problem):

I will try to keep the back story short but may help solve the problem. The power went out the other night and my old faithful return pump died. Luckily I knew he was on his way out and had a brand new backup (magdrive 9.5) ready to go. Thought it would be a quick switch but the new pump was too powerful and while I was sleeping overfilled the main display. Basically the return overflow (drilled) couldn't keep up and the pump was just to strong. Did some searches on reefcentral and installed a ball valve on the return line. Funny side note- I don't even use the "valve" as the extra adapters restrict the flow enough. I was really excited to have the problem solved and was cleaning up when I touched the main display water and.... ZAP!

The zap was just enought to hurt but not enough to cause serious pain. I tried a couple more times of course :debi: and sure enough it was some stray voltage. I got out the voltage meter and set the ac setting at 200. There are like 30 setting but that is the lowest ac setting. I registered 7.4 on the digital meter.

So I went through item by item and found the culprits: pretty much everything! The biggest culprit are my 4 aqua illumination sol LED's. They register 4.2 all by themselves!! I wonder if some water got splashed on them from the original plumbing issue but even touching the metal on the brackets gives me a real good shock.

So here are my questions for you since you guys usually help me the most:

1. What can I do to get rid of the stray voltage in the LED's? I turned them off last night but this morning still are "stray". I decided to turn them on today thinking if water was in there the heat from the lights would help "dry it up".

2. My brand new magdrive 9.5 out of the box was emmitting stray voltage of 1.2. Is that normal??

3. The tank is plugged in a regular plug that is connected in line with a GFCI in the kitchen because the tank is in the living room next to the kitchen sink. It trips if there is an issue with water getting in a plug everytime but isn't tripping for this stray voltage. What is acceptable stray voltage? Obviously not this amount as it shocks but when it is at 1.4 with the main pump running I feel nothing??

4. Almost every powerhead reads around .5 for stray voltage. Two matching ones that are 3 months old register the exact amount (.5) is this just the working "voltage" of the pump??

5. Am I using my voltage meter correctly??

Thanks for all your help and suggestions- I am really struggling with this one and I have spent the last 12 hours working on the issue-even missed a good dinner last night!

 

[Molehs]

I've always found the culprit by one-at-a-time unplugging each thing and tested to see if I still get shocked. Strangest one was getting shocked only at my sump in the basement from a powerhead in one of my tanks upstairs. I'd also assume that if you find the one, using my method, and replace or fix it, you could use a titanium grounding wire to pull off any other stray voltage.

 

[livingcorals]

Is your wall outlet even grounded?
Do you get any zaps while putting your hand in the tank? Ground probe in your sump? Sorry texting at a red light will try and catch later.

 

[saleenpwr88]

Do you have the GFCI installed correctly? If you don't, and have the line and load wires crossed, the circuit might not be properly grounded.

 

[saleenpwr88]

Good lookin tank by the way!!!

 

[ostrow]

Unplug all heaters and see if voltage still there. Then unplug everything and plug back in one by one to find the problem equipment. Replace it immediately.

Odds are heater or power head.

 

[jlnielsen13]

Thanks for the help everyone, but like I said I did the unplug test and found that everything has at least .5 v and the worst culprit were my lights at 4.2v for just the lights. Is there anything I can do with the lights? They were 2,000$ - I can't replace them. Any help in this direction is extremely appreciated. THANKS -JIM

 

[dohc97]

sounds to me like you are not properly grounded, saleen mentioned the same thing. By the way how are you measuring the stray voltage?

 

[jlnielsen13]

I am using a multimeter set at AC 200. It measures at 7.2 with everything but the lights alone are 4.2ish. I place the red in the sump and the black in a ground hole in the wall. Is this volts or do I need to multiply by something. The shock is significant- don't notice any livestock issues but am worried about me and family and fish in the long run... Should I take the lights apart and look for water/ damage??
Thanks for the help

 

[skunkmere]

are your lights touching the tank?

 

[jlnielsen13]

NO,


Not directly, they are housed in a canopy which obviously touches the top of the tank....

Can't figure this thing out! Driving me crazy- I am hoping someone has an idea out there on how I can fix these lights cause they are not replaceable.

 

[skunkmere]

the part of the light that touches the tank, what is it made of? may be you can put a piece of wood between the tank and light and see if that effects the voltage, if so find some plastic to insulate the light from the tank.

 

[lunacris86]

I would try and take lights out completly in different room let dry out for 24 no where near your tank tjen give it a shot before you plug back in canopy might need to find a way to run a fan in there just to keep dry

 

[ExFOWLR]

Unless your lights are touching the water then they can't be the source of the voltage. If you are getting shocked it is most likely from a heater, powerhead etc.., something in contact with the water like others have said. If you have a GFCI outlet it is useless unless you have a grounding wire in the water. Unless the stray voltage has a path back through the ground wire to the GFCI, it won't trip. You need to resolve this ASAP, this can be an extremely dangerous situation and can kill you dead in an instant. I take this stuff much more seriously after having to watch borderline "snuff" films at work about elecrical safety. These were videos filmed by friends and family of victims while they did ordinary things like cleaning up their flooded basements or working on things with electricity and water. One minute they are talking to the camera, a second later they are dead as a doornail to their friends and family's horror.
I don't mean to sound overly dramatic but this needs immediate attention. Don't worry what the meter is telling you, do like others have said and start unplugging things until you find the culprit.

 

[Breadman03]

My tank is new, so all of my equipment seals are fresh. My voltage reads 0.0 with the hot probe in the tank and the ground in a receptacle ground plug.

We all know water increases the risk of shock, but saltwater does so even more than fresh.
http://en.wikipedia.org/wiki/Electric_shock

 

[jlnielsen13]

Update,

Well the total is down to 3.3v on the meter after a day. It is better and doesn't shock me but I am still very concerned. All that is plugged in now is the main pump (brand new) and my AI LED lights. NOTHING else is plugged in right now- I have 12 other plugs just sitting in the cabinet NOT plugged in. The lights are attached to wood which touches the tank. When the lights are unplugged meter reads 1.2, when they are plugged in 3.3 v. HOW could the lights not be the problem???

I am so confused and really worried, I only have two things plugged in and only one of them is in the water!

Also this is weird- when I touch the glass of the sump it shoots up to 6.7v and when I put my hand in the water it goes down to 1.1? I think I am grounding the tank when I put my hand in water but why does the thing shoot up when I touch the glass.
\
I really need your help guys, your advice has been good so far but again I only have 2 things plugged in and the lights DO NOT make contact with the water but are the biggest culprit.

I ordered a grounding probe but am nervous about using it. Should this be my next step??

Thanks,
JIM

 

[fishuntbike]

Are you using the same wall outlet? What if you use different outlet? Just to see...maybe water travelled to the wires and got into the outlet.

 

[jlnielsen13]

Are you using the same wall outlet? What if you use different outlet? Just to see...maybe water travelled to the wires and got into the outlet.

Great guess, and one I had as well, I test that and thought I had to have found the culprit but in a completely different outlet with extension cord same problem...

Cant figure this one out? Is 3.3v just normal?

 

[pszemol]

Is the touching of the tank water still zaping you?
Or this 3V on the voltmeter is bothering you?

Using AC voltmeter is probably not reliable and misleading in your case...
In general, all devices connected to the mains will add to the stray currents flowing throug the water. Even the best electrical insulation is not perfect and will cause minute current leakage. You will also have some capacitance or inductance coupling going on, adding to the problem - especially in case of the lights not submerged in the water.

Typical digital voltmeter will have a very high internal resistance, hundreds times higher than your body resistance, influencing the voltmeter readings. Since all meters are different this reading is not a good indicator of the insulation quality of your light/pumps but if it reads only 3V I would not worry about it.

 

[jlnielsen13]

Is the touching of the tank water still zaping you?
Or this 3V on the voltmeter is bothering you?

Using AC voltmeter is probably not reliable and misleading in your case...
In general, all devices connected to the mains will add to the stray currents flowing throug the water. Even the best electrical insulation is not perfect and will cause minute current leakage. You will also have some capacitance or inductance coupling going on, adding to the problem - especially in case of the lights not submerged in the water.

Typical digital voltmeter will have a very high internal resistance, hundreds times higher than your body resistance, influencing the voltmeter readings. Since all meters are different this reading is not a good indicator of the insulation quality of your light/pumps but if it reads only 3V I would not worry about it.

Thanks,

The tank does not noticably shock me anymore. I "feel" like a feel a little bit but could be my imagination. When I add more plugs it goes up little by little though.... If it gets back to around 7 should I be worried?? What is an acceptable range? The lights really puzzle me!

Also one person on here has responded that this issue is life threatening and another not to worry- I am somewhere in between but wonder if I should call an electrician?
Any additional help is BIG time appreciated.
THanks,
JIM