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christyf5
05-27-2002, 02:45 AM
Hey guys,
Ok so I look into my sump tonight and notice that the protein skimmer isn't really churning out so many bubbles. I just hooked it up (Berlin XL) after getting a turbo upgrade pump for it. Anyway, I reached into the sump to turn the flow know up a bit and Zap! At first I thought maybe it was the salt water getting into a cut on my finger but the second time was definitely electrical. I unplugged everything and stuck my hand back in there and its fine with nothing on. So, besides knowing to unplug everything and the fact that none of the cords are wet what the heck is going on? I don't really know much about electrical but could it be a faulty pump or something?? Anyone got any suggestions?? (besides keeping my hands out of the sump :D )

TIA
Christy smile.gif

ron101
05-27-2002, 02:52 AM
Hmm do you have a ground probe hooked up?

The masochist's way to trouble shoot would be to plug one device in at a time and put your finger in the water after each. Whatever you plugged in just before getting zapped would likely be the culprit. Of course substituting an electrical meter for you finger would be better. ;)

[ 26 May 2002, 22:56: Message edited by: Ron101 ]

DJ88
05-27-2002, 02:52 AM
Keep your fingers out of the water. step one. but I think you know that one.

Next is get someone with a Volt meter. Put the red end in the water and the black end on a known ground source. Then one thing(pump or whaever) at a time plug things in until you see a jump in the voltage on the meter. There is your culprit. Then take culprit and take it to see the garbage dump.

Don't Don't Don't Don't test it with your fingers. please..

All it takes to kill you is 500mA. most of these gadgets use mroe than that.

Do you have a GFCI Christy?

[ 26 May 2002, 22:53: Message edited by: DJ88 ]

Jack
05-27-2002, 05:08 AM
Ouch, poor christy. That's kinda freaky. Hope you find the culprit.

PS, your SPS are doing great :D

Delphinus
05-27-2002, 11:06 AM
You should be able to pick up a rudimentary voltmeter for $5-$10 thereabouts at Home Depot, Revy, Radio Shack ... etc. You can spend a whole lot more if you want to, of course, but these cheapy ones should suffice for a water test.

One more thing to add to what DJ88 mentioned: test for AC. That's probably a pretty bluntly obvious thing to point out, but then again, maybe it's not so obvious all the time ... ;)

PS. I have been fooled so many times by the "cut on my finger" thing. I'll stick my hand in the water for whatever reason, and I'll swear I feel a current because it's a really fast kind of "zap!zap!zap!zap!zap!zap!" sensation, but then I go test, and find nothing, AC or DC (probably not needed to test DC, since there are no DC devices in there, but what the heck.)

[ 27 May 2002, 07:10: Message edited by: delphinus ]

christyf5
05-27-2002, 07:34 PM
Sorry to be duh, but whats a ground probe and how does it work??

No worries about testing it with my finger again Darren. Although I was thinking about trying it with the cat. She woke me up at 4am this morning (for the umpteenth time). Only prob is I would get cathair in my tank.

I do believe when I find the culprit (which I strongly suspect is my "new" skimmer pump) it will be going back to the store. Hopefully they have a good return policy for these sorts of things.

I'll go get one of those voltmeters, and a cute guy from home depot to work it ;) I'm getting my dad to install a GFCI first thing. The best I can do for now is a power bar with a surge suppressor which is a mighty poor substitute.

Thanks for all your help!

Christy smile.gif

Delphinus
05-27-2002, 08:36 PM
A ground probe is a titanium rod (a bicycle spoke works real well for this) that sits in your water. Any stray voltage will thus jump to ground via this probe. So if you have a GFCI, the circuit will thus trip because now there is current on the ground. So this is a great way to test for stray voltage: the GFCI will keep tripping if you have any. Of course, you still have to go through your devices one-by-one to find out which one is leaking...

You will feel real silly asking how to use a voltmeter ... ;) Basically, you will have a meter, a red wire, and a black wire. Set the voltmeter to measure AC, then plug the black wire into ground, put the wire in the water, set the voltmeter to AC (some may have different "ranges" in which case start at the highest range and work downwards). If you get a reading, you have stray voltage.

It's not hard, really, once you see one of these units you'll figure it all out. smile.gif

Aquattro
05-27-2002, 09:01 PM
Just to clarify, Tony means a titanium bicycle spoke works well for this

christyf5
05-27-2002, 10:46 PM
Tony you were right. I gotta stop picking at my hangnails :D

Christy smile.gif