Detecting Electrical Shorts

[LeslieS]

Hi Guys,

My tank set up is suddenly tripping the GFCI even though I have not made any changes. What is the best way to figure out what the problem is?

 

[Dre]

It's a good thing you have one.Do you have anything else on THAT CIRCUIT?Try unpluging everthing then plug them back one by one with a few minuites in between.It could be the G.F.I needs replacing or your fish naughing on your power head cords etc.

Do you have all the aquarium equipment on a seperate curcuit?It could be a circuit over load.

 

[masterswimmer]

Agreed.....unplug all your devices. Then plug them in one at a time. I would start plugging the devices in with your heater first. They are the most likely culprit to emit stray voltage.

When you find the one that is releasing the stray voltage, replace it.

Hope that helps a little
Russ

 

[MatthewScars]

check the heater first. they fail like crazy.

 

[LeslieS]

Thanks Everyone,

Jerry replaced the GFCI, and I slowly plugged everything in - first individually and then all together. It was working fine. A few hours later, it tripped again. How do I tell which item is releasing stray voltage?

 

[msharifa]

Here is a good technique using voltage meter that should work and identify the equipment causing trouble:

http://saltaquarium.about.com/od/aquariummaintenancecare/a/aastrayvoltage.htm

 

[Josh]

http://www.radioshack.com/product/index.jsp?productId=2999093&tab=summary

 

[LeslieS]

Thanks for the help. Jer did some testing, and he says it is both the pump and the lights. Is there any way to find out if the problem with the lights is in the fixture or the ballast?

 

[Josh]

Thanks for the help. Jer did some testing, and he says it is both the pump and the lights. Is there any way to find out if the problem with the lights is in the fixture or the ballast?

How could it be the lights? Is there any metal connecting the lighting fixture and the tank?

 

[jejton]

When you say stray voltage, do you mean voltage detected in the tank or do you only mean something is tripping the GFCI. I'm not an electrician but I believe that anything plugged into the circuit can trip the GFCI, not necessarily if its connected to the tank ( to address Josh's post ).

 

[Bob 1000]

Check all your unions and make sure there is no salt creep if there is it has a slow leak that may be leaking on something electrical.. If it's not a power head, or heater, my first thoughts.. This is also why my setups from now on will have no power heads, just bigger return pumps withe hydor flo's or maybe a wavy sea type of wave maker..
My heater just blew 2 days ago but it was old..

 

[Josh]

Leslie,

I have a multimeter if you want to test each component.

-Josh

 

[jejton]

Or you can just touch each component individually. When you're hair sticks up and eyes pop out, you'll know you have the right piece.

 

[cali_reef]

Here is what GFCI means http://www.cpsc.gov/cpscpub/pubs/99.html

Do you have anything that comes on via a timer? a device with a short to the ground typically will stay shorted, tripping the GFCI as soon as it is plugged in. Try a different heater if you can't find anything else wrong.

 

[LeslieS]

OK, the problem stopped for about a week. It started again, the night of the thunderstorm. Is that just coincidence? I feel really dumb because I just cannot wrap my mind around how electricity works - voltage vs. amps, etc...

Do you have anything that comes on via a timer? a device with a short to the ground typically will stay shorted, tripping the GFCI as soon as it is plugged in.

My lights do come on with a timer. What does it mean when a device has a short to the ground?

Leaving the heater unplugged does not seem to help. After much fooling around, it seems that I cannot run the MH light and the pump at the same time. Any other combination of equipment is fine.

Jer has a digital multimeter so I followed the directions posted earlier:


How To Test for Stray Voltage

1. Purchase or borrow a voltage meter. They can generally be found for less than $20 at most automotive parts or hardware store.
2. Turn the selector to "120 AC Voltage".
3. Insert the tip of the black probe into the third or "grounding" hole in an electrical outlet.
4. Insert the metal tip of the red probe into the tank water.
5. Watch the meter needle for any movement. Any needle movement indicates a voltage leak in your system.

Here are my results:

Tank with nothing plugged in - .16
Tunze nano powerhead - 8
2 Maxi Jet power heads in the tank - 7-8 each
Maxi Jet in the sump - 12
Heater - 15
chiller - 0
pump - 33
Everything plugged in at once - .4 shouldn't this be the sum of each piece of equipment indiviually.

Does this make sense? Shouldn't everything be 0? How do I test my lights? The lights do rest on top of the tank on metal legs, but they are not touching water.

Thanks again for all the help!