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Delphinus
04-13-2002, 06:19 PM
Every so often I test my tank with the multimeter to make sure I find nothing. Yesterday I found something. I got no DC reading, but I got a slight nonzero AC reading.

The thing is, the heater and all pumps, essentially all submerged items, were unplugged. All that had power was the lights and the fans in the canopy.

Does this make any sense?

I'm going to try the test again, this time with the lights and canopy fans off. If I get a zero reading with them off I guess I've found my cuplrit; but ... there's no contact with the wiring to the water? How can I get a current?

The only thing I can think of is that the ground I used is on the same circuit as the lighting, but even so I'm not sure it makes sense to me yet.

[ 13 April 2002, 14:19: Message edited by: delphinus ]
One_Divided
04-13-2002, 06:28 PM
I had a current leak from a fan.. Seemed a little strange since it was mounted in the hood, but I stucka gorund on it and no leak since.. I still haven't figured out what is causing the fan to leak though..
titus
04-13-2002, 08:23 PM
Hello Tony,

I don't think there's a need to worry here. AC voltage can be induced by many different means.
goldrimtang
04-19-2002, 01:56 PM
I had a good deal of voltage in my tank coming from my lights. I'm positive about it. I grounded the canopy (it's metal) and the voltage disappeared. How the electricity made it's way to the water ? I've no idea.
FishGeek
04-19-2002, 02:43 PM
how do you ground your lights. I have a metal canopy, with all the flourecent ends mounted on the metal directly. Can I just connect a grounding wire to the canopy and plug it into the electrical socket?

Simon
titus
04-19-2002, 03:54 PM
Hello,

What's the voltage range are we talking here? Voltage can be induced.
Delphinus
04-19-2002, 06:13 PM
In my case it's 1 VAC. It's barely a bump on my smallest AC sensitivity which is 0-10 VAC, higher ranges it doesn't hardly show up at all. But it's there...

(BTW, I can't measure AC amps. I can only measure DC V, DC amps, and AC V. DC V is zero as is DC amps.)

My fans are grounded as is the metal conduit I use to mount the sockets to my canopy, but that's not to say there is not a break in the wires. I've been out of town so I haven't been able to chase this down yet. Now that I'm back I think I'll double-check my grounding wires...
titus
04-19-2002, 07:57 PM
Hello,

You don't have any DC voltage/amp because you have AC sources only and there's no leak from any electronics. If you measure AC voltage but no amps that highly suggest the voltage is induced. I wouldn't worry about it.