two pumps- both have shorts!

[mariner]

Mag 7's have a problem with shorting out. I've read many other posts and have experienced this problem myself. Never had any problems with the mag 9 though.

 

[TMIB]

I stuck my hand in the sump today to move something and got a little jolt of electricity. Turns out not just one, but TWO of my pumps were shorting. With either pump plugged in, I could feel a strong jolt of electricity in the sump water. I've got them plugged into a GFCI, but they didn't trip it. I have a ground probe in my main tank, and I thought the water column connecting it to the sump would be enough. I pulled both pumps out, and will also look into making a ground probe for the sump.

FWIW, the pumps were a Mag7 and a RIO 2500.

--TMIB

 

[Anonymous]

Could the grounding probe be the source?

It seems odd to me that 2 pumps would short.

How's your grounding probe connected? Into you house electrical ground? Wire run to grounding rod outside?

 

[John G]

First, I have had 2 Rio pumps short out on me (not at the same time). One was in the sump, one was in the tank for circulation. I guess I got lucky that I didn't have a "fish fry" when the one in the tank went!!

2nd, I discussed this with an electrical engineer friend where I work. He recommended a ground probe in BOTH the tank and sump, since they are most likely not directly connected. I currently only have one in the sump. This will be changed tonight.

If the pumps shorted out, then they are probably shot, or should be replaced just as a precaution. It could just be stray currents. I used to get similar "jolts" when I put my hand into the sump. This seemed to go away after I put the grounding probe in the sump.

Hope this helps a bit?!?!!?

 

[John G]

Sorry, forgot to add. The pumps probably did not short. If they did either the GFR or the main circuit would have tripped.

 

[TMIB]

Good point John-- I hadn't considered that. Now I'm even more convinced that the issue was just induction voltage.

I'll put a ground probe in the sump and report the results.

--TMIB

 

[mariner]

They could have a hair line crack in them and that would allow the electricity to leak in to the tank. That was my case. Just don't get another mag 7. They are bad news.

 

[TMIB]

I just read some articles on induced voltage in aquariums:

http://www.aquarium.net/996/996_5.shtml

http://www.aquarium.net/1298/1298_3.shtml

http://www.reefs.org/library/article/s_brown.html

And now I'm wondering if perhaps these pumps did not have shorts after all, but were "leaking" stray voltage into the sump via induction.

I have a ground probe in the main tank, but I think I'll add another to the sump. It may be perhaps that I can put these pumps back in. Guess I should test with the voltage meter this time though, rather than get shocked by sticking my hand in...

--TMIB