[MISTERFIXIT]

Hey Guys and Gals,

Got a stray voltage 32 millivolts? Any thing to worry about?
Set up 2 pumps in a DIY sump and skimmer set up.

Marc

[smidoid]

Put an RCD on your main feed and see what happens!

[Steven Pro]

I found this article on stray voltage to be rather compelling,
http://article.dphnet.com/cat-02/strayvoltages.shtml

[smidoid]

Originally Posted by Steven Pro

I found this article on stray voltage to be rather compelling,
http://article.dphnet.com/cat-02/strayvoltages.shtml

Nice find, Steven! Confirms what I said though, everyone (including me - because I don't to my shame) should use an RCD - called a GFI in this article; I assume that's UK/US English disparity.

RCD = Residual Current Detector
RCCB = Residual Current Circuit Breaker.
GFI = Ground Fault Interuptor (NOT indicator!)

These devices kill the power to your tank if a stray current (i.e. one that shouldn't be there) appears.

I've had personal experience of both full belt UK mains at 240V to earth (through me) and it hurts - and of the same effect using a GFI/RCD. These things are so fast (thousandths of a second) you don't even notice you've been shocked, the power just goes off. Used to happen about once every day when I was an electronics apprentice - some idiot would usually plug himself in!

Edit: I probably should add, that for safety of the tank inhabitants - we should probably all have one of these suckers on each feed - certainly for the essentials like the heaters and pump(s)! Would be a crying shame to lose an entire system just for the sake of a faulty light!

[The R/C Man]

I agree with having GFI's on our tanks for both the inhabitants and ourselves. However, I believe the main circulation pump should be excluded if external. If that gets intrupted when you are away for the day, you may come home to a graveyard.... Anythoughts?

[smidoid]

So soon? Interesting thought Greg. If mine goes off, my sump will probably overflow slightly. Which begs the question - how long can the livestock survive without circulation?

I doubt the GFI will do the fish any good - there's no circuit through them as such; as for us, I've had some shocking times with my old freshwater tank! Who knows. The article Steven found is certainly food for though and his math checks out as far as I can see with my blurry 4am vision.

[BubbaWPB]

It is always a good idea to use a GFCI (or RCD) when mixing water and electricity. It is also a good thing for tank inhabitants to add a titanium grounding probe. They are one of the least expensive pieces of equipment you can get for your tank and can have a very beneficial effect on the tank inhabitants.