Please help with stray voltage in tank..

Paul B · Jun 1, 2016

If your voltage is anything less than 110 volts, don't worry about it. It is not from anything faulty. Any AC electrical device will induce voltage in anything near it. If you walk under a transformer over the street some voltage will be induced into your head. You know those guys with the purple Mohawks? They walked under a lot of transformers. GFCI's are not affected by induced voltage and you should not be either.
If the reading is 110 or higher, that comes from a short and when you stick your hand in the water, you will be thrown across the room so you will not need a multimeter to tell you there is a problem.
(Master electrician 40 years, retired)

nanomania · Jun 2, 2016

melev said:
Glad to see you are using a relay. Maybe you can put that in a project box, which is a small plastic box with four screws to keep electronics safe.

I jus bought it, but its not working.. dont know why... so i attached without it... will be trying again usin that 1 round n 1 flat wire..

nanomania · Jun 2, 2016

Paul B said:
If your voltage is anything less than 110 volts, don't worry about it. It is not from anything faulty. Any AC electrical device will induce voltage in anything near it. If you walk under a transformer over the street some voltage will be induced into your head. You know those guys with the purple Mohawks? They walked under a lot of transformers. GFCI's are not affected by induced voltage and you should not be either.
If the reading is 110 or higher, that comes from a short and when you stick your hand in the water, you will be thrown across the room so you will not need a multimeter to tell you there is a problem.
(Master electrician 40 years, retired)

What are ur thoughts on grounding probes?

Paul B · Jun 2, 2016

My thoughts are that you need a grounding probe on any tank, pond or swimming pool. It is common sense. You are putting devices in there that run on line voltage of 110 volts. When something goes wrong and a trigger fish decides to bite through the wire or it just breaks from wear, that provides a path to ground for the current rather than go through you. Of course if you don't care about that, then don't use a probe.
I make mine from a spoon, knife, radio antenna or any piece of stainless steel or silver. I don't like to mention ground probes because 746 people will come on here and argue about their use. Those are my opinions.

nanomania · Jun 2, 2016

Paul B said:
My thoughts are that you need a grounding probe on any tank, pond or swimming pool. It is common sense. You are putting devices in there that run on line voltage of 110 volts. When something goes wrong and a trigger fish decides to bite through the wire or it just breaks from wear, that provides a path to ground for the current rather than go through you. Of course if you don't care about that, then don't use a probe.
I make mine from a spoon, knife, radio antenna or any piece of stainless steel or silver. I don't like to mention ground probes because 746 people will come on here and argue about their use. Those are my opinions.

For sw, which titanium g probe u suggest?

melev · Jun 2, 2016

nanomania said:
I jus bought it, but its not working.. dont know why... so i attached without it... will be trying again usin that 1 round n 1 flat wire..

Sounds like it wasn't wired correctly. You said you are on 220v power. Where are you located?

Paul B · Jun 2, 2016

nanomania said:
For sw, which titanium g probe u suggest?

Any one you can buy, they are all the same or like I said, any piece of stainless steel.

roosterchef · Jun 2, 2016

Paul, what is the difference, from an aquarist's point of view, between a gfci on the outlet that supplies the tank, and one in the panel that shields the whole circuit? Equally effective?

nanomania · Jun 2, 2016

melev said:
Sounds like it wasn't wired correctly. You said you are on 220v power. Where are you located?

Im from india

nanomania · Jun 2, 2016

Paul B said:
Any one you can buy, they are all the same or like I said, any piece of stainless steel.

Wont stainless steel be bad in sw?

Paul B · Jun 3, 2016

roosterchef said:
Paul, what is the difference, from an aquarist's point of view, between a gfci on the outlet that supplies the tank, and one in the panel that shields the whole circuit? Equally effective?

Both are effective, use either one.

Nanomania, No. It is fine. I have quite a lot of it in my reef and it is running now for 45 years, how bad could it be!

nanomania · Jun 3, 2016

Paul B said:
Both are effective, use either one.

Nanomania, No. It is fine. I have quite a lot of it in my reef and it is running now for 45 years, how bad could it be!

So just attach copper wire to the spoon, silicone it and leave the wire in the earthing hole... right? Can u post a pic?

Paul B · Jun 3, 2016

Attach a wire to a spoon, fork, knife or a piece of stainless steel wire. Bend it over the side of the tank so you can connect the wire outside the tank. No need for silicone. Connect the other end of the wire to a ground, like the center screw of an outlet, water pipe, metal sewer pipe or a stack in the ground. That's it.

Don't put the wire in the tank even with silicone.
I don't have a picture, it's in my book but I don't expect you to read it just for that picture. If you can't figure it out I will draw a picture.

melev · Jun 3, 2016

Why not just buy a grounding probe at your local fish store or online? They cost about $6.

Paul B · Jun 3, 2016

Melev, anyone can do that, where's the fun?

melev · Jun 3, 2016

Paul B said:
Melev, anyone can do that, where's the fun?

I don't want a spork in my sump. lol

Paul B · Jun 3, 2016

Then use an eggbeater or the bumper from a 1957 Oldsmobile. Get creative but a ground probe from a store is so yesterday.

melev · Jun 3, 2016

Paul B said:
Then use an eggbeater or the bumper from a 1957 Oldsmobile. Get creative but a ground probe from a store is so yesterday.

DrayB · Jun 3, 2016

from what i've read..... i have a couple of points disguised as questions

seeing that you use 240v and in india I'm assuming your supply is ac? i'm also assuming due to the relationship between uk and india that if you are using 240v ac the you would probably be using a similar type of earthing arrangement ...tt (terra terra old style)....or tncs (terra neutral combined separated) for your mains supply safety system? if so i wouldn't fit an earth (grounding) rod as you could then be mixing two different types of earthing system and probably going to create a problem with the (potential fault path) of your system. if you had an electrical fault with your system then you would want the designed fault path to do the work of protecting the system.

if you are going to do anything then i would look to earth your tank back to the board and use the intended bonding path in there. do you have RCD protection at the board?