Stray voltage causing issues in tanks!
- Thread starter islandguy11
- Start date
The circuit breaker is so the wires do not overheat and burn your house down. This could happen if you have a short circuit or you just plug too many things into the wall.
that type goes in the circuit breaker box. it protects every Outlet on that run of wire.
The other type, the type I have, just replaces any wall outlet.
If you put it on the first Outlet from the box it will protect all the other ones farther from the box on that run.
A run is just a string of parallel outlets that run from 1 breaker.
Thx Ulu, I was hoping some peeps would bust out their multimeters and test their tanks -- I suspect if everyone on MFK did, that more than a few would be shocked by the results lol.
I've got all my tanks down to about 2vac stray voltage, to get rid of that I would probably need to use a ground probe.
Stupid question, how to properly test for DC voltage in tank? -- besides flipping the switch over on multimeter to DC, would you still connect the black probe to ground or would both probes go into the tank?
Btw are you using a analog or digital multimeter? As a side point I read that analog multimeters are actually more accurate for measuring DC, digital ones (except maybe very best ones) are susceptible to some kind of interference that can throw off readings somewhat.
The digital ones tend to flicker on DC. I have both kinds but I used a digital for this test.
When testing for DC potential I did it several different ways.
I put one probe in the tank and the other one in the sump.
I put one probe in the tank and the other one on a ground terminal of my power strip.
I tested from 1 tank to its metal stand, and from the metal stand to the sump.
I tested between three different tanks that are in the same room.
I didn't test just by putting two probes in the water of the same vessel because I wasn't expecting Loop currents.
My understanding is that most of these stray currents come from the fact that no electrical insulation is perfect and depending on the current present a certain amount of voltage will eventually leak through it, just the way that a certain amount of heat will leak through the insulation of your house.
I don't understand how magnetic fields from Motors or heaters could induce measurable currents in the water, unless you have these items so close together they almost touch.
I'll have to think about this some more.
When testing for DC potential I did it several different ways.
I put one probe in the tank and the other one in the sump.
I put one probe in the tank and the other one on a ground terminal of my power strip.
I tested from 1 tank to its metal stand, and from the metal stand to the sump.
I tested between three different tanks that are in the same room.
I didn't test just by putting two probes in the water of the same vessel because I wasn't expecting Loop currents.
My understanding is that most of these stray currents come from the fact that no electrical insulation is perfect and depending on the current present a certain amount of voltage will eventually leak through it, just the way that a certain amount of heat will leak through the insulation of your house.
I don't understand how magnetic fields from Motors or heaters could induce measurable currents in the water, unless you have these items so close together they almost touch.
I'll have to think about this some more.
Yes that's one type of GFCI, and as Ulu mentions you can get these other types to protect individual wall outlets:
Here in Thailand for some reason I think GFCI are also referred to as RCD (residual current devices), but I'm not sure if they're exactly 100% the same.
Musing to myself... Maybe it has to do with free ions in the water getting charged up from the magnetic field.
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Yes that's the type that I have protecting my new indoor aquarium and outdoor patio tank and sump Electrics, plus I have it in a waterproof plastic covered receptacle.
It's what they call an "in-use" receptacle cover.
Photograph shot at night with a Flash. This is the in-use receptacle cover on my patio.
