Stray voltage question

[twilliard]

Im not sure where to put this one but I am hoping Don or Boomer has some info for me.

After a long battle of coral color issues I decided to drop meter leads into the tank. Well one to ground and the other in the tank

I have 8.14V in my tank to ground.
I guess my question is at what point is it too much for my poor corals. I have been battling issues from day 1 of setting this tank up.

Any thoughts?
Thanks all!

 

[twilliard]

Update

The voltage INCREASES when I start to unplug pumps.
I stop unplugging when I hit 35 volts.

 

[Jim Hart]

Turn off every thing, power things and plug things in one at a time measuring at each item added. That sucks .

 

[Damsel13]

I think I have to do this...have been putting it off.

 

[Scooterman]

Ground probes with a GFCI is a good package to have but at 35 volts it is probably an induced voltage. Lots of times Lighting does this so unplug them & retest. You can do as Jim mentioned, plug in one item at a time & may find the device, usually weak or faulty grounds will cause problems also, last check all of your submerged equipment as these can be problematic over time.

 

[DonW]

Ground probes with a GFCI is a good package to have but at 35 volts it is probably an induced voltage. Lots of times Lighting does this so unplug them & retest. You can do as Jim mentioned, plug in one item at a time & may find the device, usually weak or faulty grounds will cause problems also, last check all of your submerged equipment as these can be problematic over time.

Agreed, its probably induced and is more likely harmless. If there were some sort of leak like a power head gone bad youd see more than 90vac. 35vac at almost no amps would be harmless.


Don

 

[Jim Hart]

salt creep down a power cord?

 

[DonW]

salt creep down a power cord?

Salt creap would have to be painfully obvious before there is enough build up to carry any amperage.

Don

 

[twilliard]

Woe guys, no need to kill each other over this.

I just wanted to know if induced voltage is good or bad and at what amount is it bad. Thats all.
I have been an electrician now for 14 years and know the ins and outs to this.
I just need to know at what point is it bad.
Thanks Don and scooter- I always read what you post.

 

[Frankie]

About the current going up when unplugging pumps I am a little confused. Wouldn't it go down if anything? or is unplugging them allowing more current from the source to get through? As if there not pulling the energy away from the source once cut off.
I had a similar problem way back with my amp master pump and Mojo recommended that you don't need to ground these pumps due to the way there built. But did recommend a grounding prob for the whole system which ended my issues btw.

 

[DonW]

About the current going up when unplugging pumps I am a little confused. Wouldn't it go down if anything? or is unplugging them allowing more current from the source to get through? As if there not pulling the energy away from the source once cut off.
I had a similar problem way back with my amp master pump and Mojo recommended that you don't need to ground these pumps due to the way there built. But did recommend a grounding prob for the whole system which ended my issues btw.

Frankie, there are way to many unknow factors. Yes the voltage can go up or it can go down depending on the direction of the magnetic pole and the other equipment near by. We would have to get deep into Faradays law to understand exactly where each of the 35vac in question is comming from. Its just not worh it.

Don

 

[Damsel13]

ummmmm.......is it bad if you see sparks when you plug a powerstrip into a wall outlet? and if your computer makes a noise when another electrical unit like a desk light is turned on?

 

[Frankie]

Thanks for the reply Don.
Deb, sparks are not good i have to believe

 

[Scooterman]

We can really drill this to death if your worried about that little voltage, I would check your devices & see if you can find an obvious problem. Using a GFCI & a GP is typically the way to go if your coming up with a voltage issue, I guess I can go measure my tank and see what i get but not really concerned at this point. I suggested before & now, you need to remove & clean your PH & devices that go in the water at lease twice a year & do a through inspection under bright day lights to check for cracks, open wires etc, anything obvious.

 

[DonW]

We can really drill this to death if your worried about that little voltage, I would check your devices & see if you can find an obvious problem. Using a GFCI & a GP is typically the way to go if your coming up with a voltage issue, I guess I can go measure my tank and see what i get but not really concerned at this point. I suggested before & now, you need to remove & clean your PH & devices that go in the water at lease twice a year & do a through inspection under bright day lights to check for cracks, open wires etc, anything obvious.

Just stick your tongue in the tank and ground your hand.

Don

 

[Scooterman]

Just got on circuit one 1.8 VAC & circuit two 1.8VAC but I have no PH in water, one submersible pump for the skimmer & no heater in water. I'll retest when the chiller kicks in but that is on a separate circuit also so even if I read something more not much I can do to prevent that.

 

[twilliard]

ok so to answer my question

it IS OK to have voltage in my water?

 

[Scooterman]

Do as said & check your equipment, see If you can isolate a problem but It is normal to have a voltage I shown 1.8VAC in my tank, if it was harmful we would all have a problem. I would definitely check your equipment but It may be a normal voltage for whatever equipment you have & should be of no harm. If you have a GFCI then get a Ground probe & use that GFCI with it, do not use just a GP without the GFCI, reasons is, can be a long drawn out discussion but in short IMO it isn't safe. This voltage your seeing isn't like you put bare wires in your water & shocking your tank, In most cases it is inductive voltage & is harmless, you would know quickly if it was real or a serious threat, you would feel it, fish dead coral dead etc, & it would be quick.

 

[Jim Hart]

"The voltage INCREASES when I start to unplug pumps.
I stop unplugging when I hit 35 volts"......

This concerns me, I'd stiil try to see what is causing it to spike @35v, it is vdc right? Could be a sign of leakage. Do your lights sit on top of your tank or hang from the celing? Where are the transformers/ballasts? power heads would be ac voltage and would fry your tank, its probablly ligthting related.

 

[DonW]

All this technobabble just explains that yes your going to have voltage in a reef tank. As long as its induced its not a problem. A ground probe is a good option. If its real voltage it usually going to be over 90v and then needs to be addressed. I think it was Boomer that was involved in a bunch of these studies and have already proven the above. At this moment in time I have 41vac in my tank and when the halides turn on it will be 60 its all induced and Is not causing any harm what so ever.


Don