Need electrician advise - help me not get electrocuted!!

[punchy7080]

I’ve had a 300g stock tank setup for a couple years. Today I got a bit of a tingle going in to get some corals. Long story short, if I unplug EVERYTHING my voltmeter still reads like 0.3 but I don’t feel anything when I touch the water. As soon as I plug in any electrical device the stray current jumps up. I tried different extension cords, etc and am at my wits end. Two other tanks peg at 0.0 with everything on and running. How do I have stray current with nothing plugged in? Why does it jump when I add current to any device? I expected zeros until I plugged in the “bad” device. I don’t have a grounding plug, should I add one? Not on a GFCI either which I know I need. Don’t feel anything with my slides on for what it’s worth. I was lucky and need definitive direction as I’m not putting my finger in anymore . Thanks!

 

[Malum Argenteum]

I don’t have a grounding plug, should I add one?

I would (and do).

 

[Dweaver]

What is the voltage with all the devices on?

 

[punchy7080]

What is the voltage with all the devices on?

I'll have to measure when I'm back home later this week. Curious, what would that tell you exactly?

 

[00W]

I’ve had a 300g stock tank setup for a couple years. Today I got a bit of a tingle going in to get some corals. Long story short, if I unplug EVERYTHING my voltmeter still reads like 0.3 but I don’t feel anything when I touch the water. As soon as I plug in any electrical device the stray current jumps up. I tried different extension cords, etc and am at my wits end. Two other tanks peg at 0.0 with everything on and running. How do I have stray current with nothing plugged in? Why does it jump when I add current to any device? I expected zeros until I plugged in the “bad” device. I don’t have a grounding plug, should I add one? Not on a GFCI either which I know I need. Don’t feel anything with my slides on for what it’s worth. I was lucky and need definitive direction as I’m not putting my finger in anymore . Thanks!

Do you have everything actually unplugged or just off, like just power strip turned off, etc.?

 

[Northern Flicker]

I would (and do).

@punchy7080 are we talking about GFCI, or about a grounding probe?

GFCI is a 100% yes.

Grounding probe...I am less sure about. I've always wondered how safe this actually is.

 

[punchy7080]

Do you have everything actually unplugged or just off, like just power strip turned off, etc.?

I took every electrical device out of the water and used a different extension cord. Just plugging the volt meter into the ground of the unloaded extension cord with the other lead in the water I was reading like 0.3, etc. Two other systems I tested were 00.0 so I've confirmed I'm at least doing the test correctly (they were fully running tanks as well). Once I plugged anything in to the extension cord, the volts went up. Again, I assumed I could go one device at a time getting zeros until the "bad" device popped it and sent the volts up. Don't understand how I have 0.3 stray voltage with NOTHING plugged in and in the tank and how each device I plug in independently immediately adds stray voltage to the water. They can't ALL be bad... It makes NO sense to me but I'm not an electrician I'm obviously missing something, just don't know what it is... hoping someone with more experience will be able to say "do this" and will get me on the right track. I'm working towards breaking down this 300g stock tank but would like to live to see it happen LOL. Thank you!

 

[00W]

I took every electrical device out of the water and used a different extension cord. Just plugging the volt meter into the ground of the unloaded extension cord with the other lead in the water I was reading like 0.3, etc. Two other systems I tested were 00.0 so I've confirmed I'm at least doing the test correctly (they were fully running tanks as well). Once I plugged anything in to the extension cord, the volts went up. Again, I assumed I could go one device at a time getting zeros until the "bad" device popped it and sent the volts up. Don't understand how I have 0.3 stray voltage with NOTHING plugged in and in the tank and how each device I plug in independently immediately adds stray voltage to the water. They can't ALL be bad... It makes NO sense to me but I'm not an electrician I'm obviously missing something, just don't know what it is... hoping someone with more experience will be able to say "do this" and will get me on the right track. I'm working towards breaking down this 300g stock tank but would like to live to see it happen LOL. Thank you!

Did you plug the extension cord into the same outlets as the 0.00 tested tank or another outlet?

 

[punchy7080]

It is a separate circuit... after I typed that last message I started to wonder if something funky is maybe going on with the outlet that's supplying power to the stock tank?

 

[BeanAnimal]

Folks - in almost all cases you are going to read "voltage" from the water to ground. That reading (unless you really understand what you are doing) is meaningless. You have no current reference and can't differentiate fault current from induced voltage (that turns to current when you use the meter).


If your meter is reading ~100 VAC or more volte then you have an issue. Otherwise put the meter away, you don't know what you are doing.

If you install a ground probe and there is an actual current leak, it will trip the GFCI immediately. Don't ever use a ground probe without ALL of the equipment on or around the aquarium being GFCI protected.

 

[Steve Zee]

Listen to Bean! I just said the following a few minutes ago on a different thread, --"And my pet peeve is why anyone puts relevance on a cheap meter with test leads dropped in the water. It literally means nothing. I can get 60 volts by sticking a probe in a potato on my kitchen counter. That’s with a True RMS meter."

DO NOT USE A GROUNDING PROBE WITHOUT A GFCI!

 

[punchy7080]

I'm not pretending to be an electrician, that's why I'm asking for help. I searched for how to test stray current in water and that's where I saw the reference to using a volt meter. So is a reasonable plan to install the GFCI outlet, have everything in this tank plug into the extension cord plugged into the GFCI and then use a grounding probe? My goal is to figure out which device is leaking current and replace. I thought the volt meter would help me do that but it's obviously not behaving how I expected (per both of your comments). Maybe I can install the above setup and then test one device at a time until it pops the GFCI? That's easy enough to do...

 

[Formulator]

Listen to Bean! I just said the following a few minutes ago on a different thread, --"And my pet peeve is why anyone puts relevance on a cheap meter with test leads dropped in the water. It literally means nothing. I can get 60 volts by sticking a probe in a potato on my kitchen counter. That’s with a True RMS meter."

DO NOT USE A GROUNDING PROBE WITHOUT A GFCI!

Folks - in almost all cases you are going to read "voltage" from the water to ground. That reading (unless you really understand what you are doing) is meaningless. You have no current reference and can't differentiate fault current from induced voltage (that turns to current when you use the meter).


If your meter is reading ~100 VAC or more volte then you have an issue. Otherwise put the meter away, you don't know what you are doing.

If you install a ground probe and there is an actual current leak, it will trip the GFCI immediately. Don't ever use a ground probe without ALL of the equipment on or around the aquarium being GFCI protected.

He said he got a jolt when dipping his hand in the water, so I wouldn’t discount the fact that something is astray, regardless of whether or not the meter is being used or interpreted correctly.

 

[Formulator]

I took every electrical device out of the water and used a different extension cord. Just plugging the volt meter into the ground of the unloaded extension cord with the other lead in the water I was reading like 0.3, etc. Two other systems I tested were 00.0 so I've confirmed I'm at least doing the test correctly (they were fully running tanks as well). Once I plugged anything in to the extension cord, the volts went up. Again, I assumed I could go one device at a time getting zeros until the "bad" device popped it and sent the volts up. Don't understand how I have 0.3 stray voltage with NOTHING plugged in and in the tank and how each device I plug in independently immediately adds stray voltage to the water. They can't ALL be bad... It makes NO sense to me but I'm not an electrician I'm obviously missing something, just don't know what it is... hoping someone with more experience will be able to say "do this" and will get me on the right track. I'm working towards breaking down this 300g stock tank but would like to live to see it happen LOL. Thank you!

Did you take everything out of the sump too?

 

[BeanAnimal]

So is a reasonable plan to install the GFCI outlet, have everything in this tank plug into the extension cord plugged into the GFCI and then use a grounding probe? My goal is to figure out which device is leaking current and replace. I thought the volt meter would help me do that but it's obviously not behaving how I expected (per both of your comments). Maybe I can install the above setup and then test one device at a time until it pops the GFCI? That's easy enough to do...

A few notes:

A single GFCI creates a single point of failure. Something to consider. Cord and plug style GFCIs have two main issues. Firstly, they often do not "self reset" after a power outage. Secondly, they are often more prone to nuisance trips than are quality receptacle style GFCIs.

If it were me. I would purchase or build a GFCI extension cord for testing. I would improvise a ground probe out of a stainless steel bolt and some wire (so as not to have copper in the tank) and do some testing.

If you want to keep the tank on GFCI then I would use multiple GFCIs. Either have your electrician add them to your circuit or build your own GFCI power snakes with quality (Leviton, Hubbel, etc.) GFCI receptacles. Individual cords with boxes and bubble covers or a few daisy chained together with conduit sections. etc.

He said he got a jolt when dipping his hand in the water, so I wouldn’t discount the fact that something is astray, regardless of whether or not the meter is being used or interpreted correctly.

He used the word "tingle". Induced voltage and cut can cause a "tingle".

Also typically if there is a fault, you will get line voltage (or pretty close) on the meter. But this is where a meter can get you in trouble too... so you get 90v on the meter. Where is the other 20-40 volts going, etc. You need to switch to current mode and do further testing. However, most people don't know how to interpret the results.

So - for most folks the meter is not a tool that they should be using.

Yes, he could have a problem.

 

[Formulator]

A few notes:

A single GFCI creates a single point of failure. Something to consider. Cord and plug style GFCIs have two main issues. Firstly, they often do not "self reset" after a power outage. Secondly, they are often more prone to nuisance trips than are quality receptacle style GFCIs.

If it were me. I would purchase or build a GFCI extension cord for testing. I would improvise a ground probe out of a stainless steel bolt and some wire (so as not to have copper in the tank) and do some testing.

If you want to keep the tank on GFCI then I would use multiple GFCIs. Either have your electrician add them to your circuit or build your own GFCI power snakes with quality (Leviton, Hubbel, etc.) GFCI receptacles. Individual cords with boxes and bubble covers or a few daisy chained together with conduit sections. etc.


He used the word "tingle". Induced voltage and cut can cause a "tingle".

Yes, he could have a problem.

GFCI extension cord is a fantastic idea. Now I need to make one! No stray current in my tank at the moment but I have been in the OP’s position before, chasing my tail with a multimeter. Never thought to use a portable GFCI cord as a test probe. Thank you for this!

 

[punchy7080]

A few notes:

A single GFCI creates a single point of failure. Something to consider. Cord and plug style GFCIs have two main issues. Firstly, they often do not "self reset" after a power outage. Secondly, they are often more prone to nuisance trips than are quality receptacle style GFCIs.

If it were me. I would purchase or build a GFCI extension cord for testing. I would improvise a ground probe out of a stainless steel bolt and some wire (so as not to have copper in the tank) and do some testing.

If you want to keep the tank on GFCI then I would use multiple GFCIs. Either have your electrician add them to your circuit or build your own GFCI power snakes with quality (Leviton, Hubbel, etc.) GFCI receptacles. Individual cords with boxes and bubble covers or a few daisy chained together with conduit sections. etc.


He used the word "tingle". Induced voltage and cut can cause a "tingle".

Also typically if there is a fault, you will get line voltage (or pretty close) on the meter. But this is where a meter can get you in trouble too... so you get 90v on the meter. Where is the other 20-40 volts going, etc. You need to switch to current mode and do further testing. However, most people don't know how to interpret the results.

So - for most folks the meter is not a tool that they should be using.

Yes, he could have a problem.

Oh, there's a problem, I can feel it I ordered a GFCI extension cord and a titanium grounding probe at least for testing. Hopefully the faulty device will trip the GFCI and then I can devise a permanent solution... for all my tanks where I'm putting hands in water with electrical equipment! Appreciate the help, please pipe in if my plan is off base at all.

 

[Paul B]

It makes NO sense to me but I'm not an electrician

I am. If you read anything less than about 100 volts, don't worry about it and go out to dinner. Maybe get a nice bottle of Merlot.

People have been asking about "induced current or voltage" since Alexandra Volta named the thing in the 1800s.

It doesn't mean anything and the 0.3 volts you are reading is just a "thing" that cheap meters will read. A triple A battery that you run a small flashlight puts out 4 or 5 times more volts than that.

But you should plug that tank into a GFI just in case your heater or powerhead breaks. That won't give you a tingle but will throw you across the room and maybe kill you.

 

[punchy7080]

I am. If you read anything less than about 100 volts, don't worry about it and go out to dinner. Maybe get a nice bottle of Merlot.

People have been asking about "induced current or voltage" since Alexandra Volta named the thing in the 1800s.

It doesn't mean anything and the 0.3 volts you are reading is just a "thing" that cheap meters will read. A triple A battery that you run a small flashlight puts out 4 or 5 times more volts than that.

But you should plug that tank into a GFI just in case your heater or powerhead breaks. That won't give you a tingle but will throw you across the room and maybe kill you.

Appreciate it... If I stand on the carpet around the stock tank or put my slides on (rubber type slippers) then I don't get much/anything. If I stand barefoot on the concrete I get an uncomfortable buzz. Something is leaking in the tank that should not be... I'd love confirmation that a GFCI extension cord with titanium grounding probe is a safe way to test and flush out the culprit. I'd like to figure this out before I get the full on jolt that throws me across the room... at best. Thank you!

 

[Steve Zee]

Please do not stick your hand back in the water unless everything is on a GFCI or everything is unplugged. My opinion is forgo the grounding probe (especially a TITANIUM one since that’s just stupid on a whole other level) as it only makes for a more dangerous situation by adding a path to ground that is closer to you when hands are in the water.

To get a real diagnostic meter reading requires a current leakage meter that reads current in mA. That means spending a minimum of $300 and then you need a lesson on how to interpret the readings. You will also need to separate the neutral and the hot to properly evaluate and that’s not easy if the cord is jacketed.

Using the portable cord with a GFCI is a good testing idea. Just make sure to separate your equipment if you are using multiple circuits in your tank and they are on different phases. That, you can check using a cheap meter. Check voltage between the hot of each outlets if it’s over 208v then separate everything for testing.

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