Stray voltage

[Bill S]

OK, I just dipped my hand in my sump to adjust my skimmer, and I got a little twinge of stray voltage... I do the same in the tank, and all is well - no tingle.

In my sump is: the probes for pH, Temp, ORP; return pump (Quiet1 600), skimmer pump, heater (new submersible, hooked to the controller from my old titanium heater that crapped out - it's now double protected by the old controller and the thermostat on the heater itself).

Without using the "tingle test", what's the best way to isolate the problem? I do have a high end multimeter...

TIA

[cpreefguy]

Have you tried a grounding probe?
http://www.marinedepot.com/md_viewItem.asp?idproduct=UL1711

[Bill S]

Hmm. Sean, that looks like a "bandaide" approach? I THINK I need to find the source? BTW, ALL except the probes for ph/Temp/ORP are on a GFCI outlet.

[JimD]

The logical approach would be the process of elimination.

[Bill S]

Jim, I understand that... OTHER THAN putting my hand back in - which I'm just plain NOT in favor of - how does one TEST for its presence?

[SBreef]

Do you have a voltage meter? If so, one probe in the water and the other to ground. Then take a reading and start to unplug things, one at a time. If not, try your heater first. Do you have a Rio pumps, if so, then try them.

[JimD]

oops... Put the + probe on your meter in the tank and the - in the ground hole on any grounded plug outlet and monitor the AC voltage on the meter using it for reference, one by one unplug the equipment and look for an obvious change in voltage. Youll most likely read in the mv range if theres no real problem and in the + voltage if there is. Make sense?

[Bill S]

Yup. Let me try it and I'll get back! Thanks all!

[JimD]

Its not uncommon to get a small tingle especialy if you have a cut on your finger around the cuticle and if you have shoes on or not. I do every now and then even with a ground probe and no measurable voltage.

[Bill S]

OK, this is WEIRD. Total sump AC voltage: 11.1 volts (like I said, just a little tingle)

If I systematically turn things off, it's the PUMPS that put out the voltage: Quiet1 6000: 3volts; Iwaki & GenX: around 2.5 volts each; Seios: .75 volts each; skimmer pump: 2 volts. Is this NORMAL? And can I get rid of it by just running a ground?

[SBreef]

I would look at the ones that are submersed.

[caferacermike]

COuld it be possible that it is stray generated voltage? You have tons of magnets spinning around and I'm wondering if any outside voltage is crawling around your gadgetry. Kinda like a radio signal. I hope I'm making sense as I'm not an electrician. I work around commercial electricians all day long (harassing them about circuitry for powering up all my pumps and timers, I'm always on about lighting questions) and also know a few things about alternators and dyno's from motorcyles and cars. From what I understand the internal voltage flows through the wiring as it should and you could say it spins with the directions of the magnets. But there is a small interferrence voltage that can build up in the opposite direction on the outside of poorly insulated devices. That's why when you install a nice stereo in your car but do not get it grounded correctly it can whine with the pitch of the alternator.

It's just a theory as you say that almost each of your spinning motors is creating a small amount of "leaking" voltage.

[caferacermike]

Oh and also just thought that you don't seem to have any current or amperage behind the stray voltage meanign that it may be coming from an alternate source. If you had any type of line amperage or current behind the voltage I'd assume it would have the oomph to push it into the main tank. It seems to have no amperage and is fizzling out in the sump.

And yes I'd assume a good ground would help divert it. And would be recommended.

[SBreef]

COuld it be possible that it is stray generated voltage? You have tons of magnets spinning around and I'm wondering if any outside voltage is crawling around your gadgetry. Kinda like a radio signal. I hope I'm making sense as I'm not an electrician. I work around commercial electricians all day long (harassing them about circuitry for powering up all my pumps and timers, I'm always on about lighting questions) and also know a few things about alternators and dyno's from motorcyles and cars. From what I understand the internal voltage flows through the wiring as it should and you could say it spins with the directions of the magnets. But there is a small interferrence voltage that can build up in the opposite direction on the outside of poorly insulated devices. That's why when you install a nice stereo in your car but do not get it grounded correctly it can whine with the pitch of the alternator.

It's just a theory as you say that almost each of your spinning motors is creating a small amount of "leaking" voltage.

As for "stray generated voltage" no! Magnetic fields yes. Your toaster, blow dryer and etc. puts out stray fields. Car stereo whine is usually bad or "undersized" ground wires. If you think about it, all of your devices has wires are are of equal size. Now if you have a smaller gauge ground wire, compared to your positive wire. then you will have a problem. I am an a electronics tech. In electronics we think of power (current) flow from, negative to positive. Electricians think just the opposite. "Stray" voltage is more likely to occur from your lights, than anything else, except maybe heaters.

[Bill S]

Roy, unplugging the heater had no effect. I'm going to try testing the amperage. I'm also going to take my old Titanium heater, and put a ground wire on it, immerse it, and use it as a ground until I get a titanium grounding probe.

[SBreef]

Bill, also check anything in the main display! Remember water is a "GREAT" conductor of electricity!!
Make sure you have no saltcreep on your light sockets.

[SBreef]

Bill,

Did you get this figured out?

[Bill S]

Well, sort of. I also get 11 volts from the main tank. But nothing seems to be particularly disturbed? And I get no zing from there with my hand in the water - the amperage must be pretty low? I've done some research, and it seems that pumps DO put out some voltage into the surrounding water - and ALL of my pumps seem to do that! And, it's AC voltage - using DC gets no indicator. I checked my 55 too - and have 24 volts there! I only have DC amps on my meter, so I didn't check the amperage. It's very low, though.

In any case, I bought a grounding probe. We'll see what happens with it.

[alton]

Bill when you check between your grounded terminal(White) and grounding terminal (green) on your duplex receptacle, is there any voltage? In the times of drought like now, we tend to lose our service ground or it gets weak. The only bad thing about a grounding probe is if you lose your service ground or it gets weak it will use your aquarium as a grounding path. (We will not mention a lightning strike)This happened to one of our LFS owners and with only 5 volts it would shock the heck out of him. General note in times of drought, soak the ground where your ground rod is installed.

[safeuerwehr]

FYI....for those of you that dont have a clue where to look, the ground rod can usually be found near the meter loop....CPS most always installs them just below the meter box....look for an exposed copper wire that leads to the dirt