Stray voltage

[wontonflip]

I am battling stray voltage in my sump. It's not travelling to the DT at all, nor in the overflows.

We went on a hunt for it, and pulled out an old pump and an old heater. No more stray voltage. We plugged everything back in, and no strays at all. A few hours later, before bedtime, I decided to check again, just to see. And stray voltage again!

So basically, why would stray voltage show up later, and not earlier? The only electrical things I have in that sump are the return pump, and skimmer pump. Both seem to be causing some stray voltage. The return pump is only a few months old, and the skimmer pump is only a year old.

Again, it is not getting into the DT at all. In the DT, there are 2 k4's, and each overflow holds a heater. No stray voltages there. So, should i worry about the stray voltage in the sump? I'd hate to think that the 2 newew pumps in there need to be replaced.

:shocking:

 

[PRC]

Did you check the cords to see if they're fraid at all?

Can you take one of the units off line? If you take 1 off line you can tell what specific unit is causing the trouble and then repair or replace.

I would worry about any stray voltage in water. You just never know if it's going to stay at a low level...We don't need any disasters!

Grasping at straws here: Can you possibly run an extension cord out of the room to another plug and see if the problem persists? Maybe it's the plug itself.

 

[ccCapt]

Maybe it's only when the pump and heater heat up that causes them to leak voltage. Saltwater is a pretty good conductor of electricity. I think if it's in the sump water, it's in all the water. It might be weaker, but I would think it's there.

 

[VAreef]

As motors run and electricity flows thru windings the windings heat up and expand weakining the insulation slightly. This is why it wasn't there right when you put the pumps back in but showed back up a few hours later. Also, if they are not properly grounded static electricity can build up from ungrounded equipment.

How are you determining stray voltage? A voltmeter? How much stray voltage? The stray voltage could be from an incomplete ground. Check to ensure ALL pumps are using a three prong plug as well as any and all powerstrips you are using. That third prong is a dedicated ground. Pump makers who make powerheads and such without that ground should be shocked themselves a few times.

If you have dedicated grounds on all equipment you should not be getting any stray voltage as all pumps would be internally grounded.

 

[wontonflip]

Ok...thanks for all the input.

To answer PRC -- I unplugged everything, then plugged in the return pump, got stray voltage. Unplugged that, and plugged in the skimmer, stray voltage as well. Nothing else was running.

I have one of those pen voltage meters....
Greenlee GT-11

Here's how the wiring is set up --

The main plug is GFCI. A power strip w/ breaker is plugged into that.
In the power strip, the 2 pumps are plugged into that.
There is also an indoor/outdoor extension cord (might be Ridgid brand), which runs through the drywall, to under the tank stand in the next room. Plugged to that is another power strip with 2 powerheads, and 2 heaters.

The first powerstrip w/ the pumps and the outdoor plug is hanging around 5 feet above the sump, no wires are anywhere near the water, except the wires for the pumps that are coming out of the water.

Ok, so I just now checked it again, NO stray voltage. wtf?

 

[Bifferwine]

Oh Wonton. I have to go to the hardware store today and buy a new fuse for my voltmeter, because I had a cut on my hand last night, and felt it tingle when I put it in my tank. So I need to test my water too. I hate stuff like this!!

I'm sorry I can't answer your questions -- I'm useless in this area :(

 

[wontonflip]

Double checked the ground, and all my pumps and even the power strip are 3 prong.

Still no stray right now. I know my voltage meter is working because if I touch a plugged wire, it goes off.

 

[VAreef]

I hate to tell you but those types of testers aren't very accurate or reliable. Sometimes just moving them wrong can set off the light. bumb it up and down on your hand and see if it doesn't tell you there is voltage on your hand. I am using all grounded plugs and when I put my fluke on the sump tank it reads 4 volts ac. nothing to worry about at all. My display tank actually reads 8.3 volts but I have one of those unsafe powerheads in it until I can get it replaced with a new one. I have a feeling the voltage in my sump is coming from the powerhead in the DT.

The pumps you are using? Do they have three prongs on the plug or just 2?

If your all grounded then most likely your just getting a little build up of static electricity. There is no telling how sensitive that pen is it could be setting off at 5 volts and not a real voltage.

 

[dcantucson]

Maybe you've got a bad meter. I hate problems like these. Mysteries in the tank. :(

 

[wontonflip]

Well, I know at one point I had major voltage -- I'm very sensitive to voltage....when I put my hand in the sump to pull something out, I felt it, and had my husband bring me the meter which prompted all the checking around. I haven't felt it since pulling out the old-as-dirt pump and theh old heater, but I was still reading voltage.

@VAReef -- the pumps are 3 prong.

It's possible the meter's bad. I still have to see it though. The meter does detect static, but the difference is that when I put it in the water, it keeps on buzzing.

 

[VAreef]

It really sounds like your just getting some static build up from the pumps. I have heard about people using stanless steel wire to ground out their tanks before to prevent this. That should also prevent a major voltage since in theory it would draw high current and trip the GFI. I would assume stainless steel would be safe in a tank but I would want more info on it before putting it in there.

 

[bjohanson1234]

If you could Wonton, use an actual voltmeter. Those pens can be really sensetive and actually indicate voltage almost a foot away from the source.

As for the ground probes, they sell them made out of titanium.

Brian

 

[Bifferwine]

Wonton, you can get a voltmeter for around $8 to $10. Definitely worth it!

 

[VAreef]

As for the ground probes, they sell them made out of titanium.

OOO good deal titanium does do well in saltwater. Even better than the best stainless alloy I bet.


And definitly buy a basic voltmeter they are so so useful around the house as well as just checking an aquarium.

 

[PRC]

Ok...thanks for all the input.

To answer PRC -- I unplugged everything, then plugged in the return pump, got stray voltage. Unplugged that, and plugged in the skimmer, stray voltage as well. Nothing else was running.

QUOTE]



I would care to bet that it's something else. The odds of both of those units being bad and giving off stray voltage at the same time is IMO unlikely.

1. Run a different extension cord as far away from the tank as you can. (that way it will probably be on a different circuit on the breaker box)
2. Hook up a different power strip to the extension cord.
3. Plug one thing in at a time. Maybe wait 10-15 miinutes before pluggin something else in. (Grasping at straws here, but maybe the electricity needs to build up)
4. Keep adding one thing at a time until you get a spike in electricity. If you don't get a spike once everything is plugged in, it can only be one of 3 things. (extension cord, power strip, house circuit)
5. Now replace the power strip with the one you normally use. Nothing? that's not it.
6. Now replace the extension cord with the one you normally use. Nothing? That's not it.

If you've gone through all of these steps and still don't have the stray electricity, it's the circuit (wall outlet) that you're normally using.

I would also check for any frayed cords for each device...

 

[Bifferwine]

Wonton, PRC is right. I had a faulty power strip causing stray voltage in my old 240. Everything that was plugged into it was acting screwy. You have to check every step of the connection.

 

[wontonflip]

Thanks all!

I'm going to monitor things. I'm definitely not hooking up the old-as-dirt pump, because with that one, I could actually feel the voltage, so that one is probably bad anyway (I tested it in a tub of water far from the tank, and it was wonky).

I think it might also be the power strip -- it's not old, but it's not the more expensive one, either. What did you end up getting, biff?

I will also try plugging the power strip to another outlet far from the sump room, as per PRC's suggestion....but I'll do that if I detect stray voltage again. Not like I can tell if there's a real problem if it's not happening :)

I feel much better! Odd thing is that the mushrooms are in the intake sump, and they were fully opened up and seemingly doing well everytime the lights were on. At the time that I felt the voltage the first time, they seemed fine.

 

[Bifferwine]

I got two of the heavy duty shop power strips from Home Depot, Wonton.

These ones:
Belkin 10 Outlet Metal Surge Protector - F9D1001-15-DP at The Home Depot

 

[wontonflip]

Gotcha!! Thanks :) And I loke how it has a lot of outlets. Nice price, too. I'll probably go pick one up.

 

[wontonflip]

OK apparently I"m one big ball of walking static electricity LOL I tested the water right under the light with the meter, and it beeped. My husband did the same.....nothing....I did it again....beeped LOL He had me take off my slippers (rubber), no beeping. I put them back on, it beeped. I'm like, Dr. Doom or something LOL