60v stray voltage is this a problem? Any charts / guides for acceptable amounts?

jd-woodlands · Feb 14, 2020

Been having issues with an apex port that my heaters are connected to, so worked on it this morning to troubleshoot. Hands in water I feel I a good amount of electrical current on some nicks and cuts on my hand.

grab the electrical and test, 60v - 90v of current... should I be concerned? Turned off heaters one by one, and isolated one with +50V of leakage. (Cobalt Neo therm).

Should I discontinue use of this heater?

how much is too much stray voltage?

Should I be measuring amperage or resistance?

Any charts or guides on acceptable values?

motortrendz · Feb 14, 2020

Yea that's definitly too much. I've only ever measured about 3 or 4 volts. Once I added a ground probe I read zero. But that much is pointing towards a bad heater.

NeonRabbit221B · Feb 14, 2020

If you can feel it, I would replace the heater. Happened to me a few weeks back.

I would say 30-40V from a single source is significant.

Miller535 · Feb 14, 2020

That is a very dangerous amount.

Definitely replace

Miller535 · Feb 14, 2020

You measure in voltage. I would expect to see zero, I could possibly be ok with .1, .3 volts or something. Anything else is not ok

jd-woodlands · Feb 14, 2020

Hmmm ok, thanks for the inputs, when I turn the suspect one off I Get down to 12v, a few more devices off I get down a few more volts lower at a time.

guess I’ll trash that heater and setup a grounding probe To be safe if that will fix it?

or does it sound like I have some other issue?

Any quick links to setting up a grounding probe?

madweazl · Feb 14, 2020

jd-woodlands said:
Hmmm ok, thanks for the inputs, when I turn the suspect one off I Get down to 12v, a few more devices off I get down a few more volts lower at a time.

guess I’ll trash that heater and setup a grounding probe To be safe if that will fix it?

or does it sound like I have some other issue?

Any quick links to setting up a grounding probe?

Looks like you're going about it the right way. Just unplug a single device at a time to find what is creating the issue(s). If you can avoid submerging the heater, do so (one less thing to worry about). I believe under 40 is considered low voltage.

Miller535 · Feb 14, 2020

I would try the grounding probe. I believe the rule of thumb with a grounding probe is just to put it as close to your heaters and pumps as possible. The one I have screws to the ground screw of an outlet. I like that because it can't be bumped or accidentally pulled out.

I have this one:

LARedstickreefer · Feb 14, 2020

Throw away the heater.

LobsterOfJustice · Feb 14, 2020

Trash that heater ASAP. What your are describing is typical. It is hard to find anyone recommending a definitive amount but somewhere in the 8-12 V range (total) is reasonable. Typically you will get multiple devices each contributing a few V each. You can’t replace everything so that you just have to live with. But if you can identify any single piece of equipment contributing 10 or more V just by itself, that is no good and needs to be replaced.

jd-woodlands · Feb 15, 2020

Thanks all for the info, trashed the Cobalt NeoTherm 100w (already RMA once, this was a replacement they sent) that was putting out 50V+of stray voltage.

That dropped me to 9V total, installed a grounding probe today and went to 0.3V.

assuming this was the cause of losing a nice male blue throat trigger, was perfectly fine and healthy. Also had a few jumpers lately as well that went tile surfing - could have contributed there as well.

Joekovar · Feb 15, 2020

Well, old POTS phone lines would put out about 70v when someone was holding the wire and you called the line, which was enough to make them jump and call you a m**********r.

I could definitely see 50 being enough to have fish trying to jump out of the tank.

Cory · Feb 15, 2020

Measure the amperage the same way you did voltage. Amperage is a true electrical leak. Stray voltage is usually induced magnetic fields producing voltage from the water around it. But 50v is most likely leaking amperage too.

krash7172 · Feb 15, 2020

I don't know what fish can tolerate but 24v is considered safe in the electrical world.

LobsterOfJustice · Feb 19, 2020

jd-woodlands said:
Thanks all for the info, trashed the Cobalt NeoTherm 100w (already RMA once, this was a replacement they sent) that was putting out 50V+of stray voltage.

That dropped me to 9V total, installed a grounding probe today and went to 0.3V.

assuming this was the cause of losing a nice male blue throat trigger, was perfectly fine and healthy. Also had a few jumpers lately as well that went tile surfing - could have contributed there as well.

To be clear, adding a grounding probe does not solve the source of the remaining voltage - it just gives voltage (potential) a path to ground, turning it into current. The electricity is still there, it’s just that you can’t measure it when it’s grounded.

W1ngz · Feb 19, 2020

60v is definitely high, but voltage isn't the problem. A perfectly functioning tank that isn't grounded will still show a voltage because of the motors and heater coils that are sitting in a saltwater electrolyte. Depending on the equipment you have that might be 0.1v, it might be 20v or 30v, but it's a meaningless number since electricity is carried by current, voltage is just the potential of how much current there could be.

To properly isolate and identify the offending equipment, you need a ground probe and a GFCI outlet. When too much current passes through the ground instead of the outlet, the GFCI will pop letting you know that something dangerous is going on in the tank.