Mag 9.5 problem?

[Joel]

I have a Mag 9.5 that I use for mixing water and it recently started tripping the gfci plugs in my garage. I tried all plugs in the garage and even 1 in a bathroom in the house. Same result. So like a true reefer I took a bucket of water, put the pump in it, plugged it into a non gfci plug, and stuck my hand in the bucket. It didn't shock me and works fine. Why would this pump do this and is there any way to fix it. The pump is about 1 year old.

[ScoobityDoobity]

I had the same problem with my pump. YOU WILL NOT FEEL the shock at first. It is so slight. So I overlooked the GFCI tripping and plugged it into another plug that was not GFCI. I just thought it was the plug. It ran about another month and one day I stuck my hand in and WHAAMMOOOOO!!!!!! It got me!!!! I replaced the pump and everything is returning to normal. I say normal because it was the root of my tank crashing on me a little while ago. Not only was there electricity leaching into the water, BUT there was also RUST! My tangs got lateral line errosion, my softies died, even Xenia, polyps wouldn't open, SPS died off quick like, shrimp and most of my crabs died, also snails. I believe most off the die off was due to the rust. And you don't have rust by itself, it comes from something shorting out!!! Hindsight for me is 50/50!! You have your stuff plugged into the GFCI for a reason. LISTEN TO IT!!!!

[Joel]

K, I guess its a good thing I just use it to mix water! Anybody have a used mag 9.5 or 12 for sale?

[mjsandbe]

I find this rather scary, I have a MAG 9.5 as the main pump in both of my tanks.

[Joel]

I guess if you have gfci breakers there shouldn't be anything to worry about. My main pump in the tank is a 9.5 but the one in question is the one I use for mixing water.

[Joel]

I was getting ready to take out the trash just now and throw away the 9.5 when it occurred to me that the pump may indeed be fine. Since it was going out in the trash anyway I cut off the plug installed a new one and guess what, it doesn't trip gfci breakers anymore. Maybe this info will save someone a little money if they have a bad plug and not actually a bad pump.

[snazlord]

wow. could you elaborate a bit? was there anything visibly wrong with the plug? cracked insulation or something?

and i'm a complete novice when it comes to electrical stuff, but you "cut off" the plug???!!! How do you put a new one on? just twist the wires around each other and twist some end-caps on them, and wrap them with insulation tape? That seems like it would be an easy way to get shocked, with wires being sort of "exposed?"

again, i'm sure i sound like a total idiot about this, but i am truly ignorant in this regard. (and i have a mag 12 submersed in my sump as my main return, and my GFCI tripped for the first time a few days ago - i just reset it, and it hasn't tripped since...)

[Geoff]

check the impellor assembly. sometimes the magnet that gets inserted in to the body of the pump will get encrusted. this can cause a huge load on the pump. make sure to clean them several times a year.

G~

[Joel]

You just have to cut the old cord off at the plug, cut the insulation off the wire and attact the new plug. The replacement plug comes apart with a small screwdriver and the wires attach to the plug with screws. There was no visible damage to the original plug. I replaced the impeller and housing (cracked) recently so there are no deposits on it at all. And I also cleaned the pump with vinegar to remove any deposits where the impeller goes.

[sfletch3]

Before I got into computers, I was an electrician. When I read about the way you test your GFIC outlets, I nearly had a stroke. It takes milliamps to kill someone. Had you been touching anything else that would provide a path of least resistance, they could have been burying more than just a dead pump. All you need is a few milliamps to pass across you heart and it can stop it. It's lucky that when ScoobityDoobity got shocked it must have pass through one arm and down through the leg on the same side so as not to pass across the heart. All kidding aside, PLEASE, don't try this at home. We would like to keep you all posting and answering questions on the web.

[sfletch3]

Electric Current
(1 second contact) Physiological Effect
1 mA Threshold of feeling, tingling sensation.
10-20 mA
"Can't let go!" current - onset of sustained
muscular contraction.
100-300 mA Ventricular fibrillation, fatal if continued.

[Joel]

I'll admit the bucket test method isn't the smartest way to test for stray voltage but I wasn't thinking about that at the time. And luckily no harm done. So with that said how do you correctly test for stray voltage?

[sfletch3]

This can be a little complicated. Basically electricity doesn't stray. If you think of electricity like you would think of water it might be easier to understand. The wire insulation is equivalent to the water pipe and the water is the equivalent to the electricity. A switch is equivalent to a valve. So like at home the water company pumps water to your house. Until you open the faucet the water is just waiting. Once you open the valve (faucet) the water flows into the house. Same with electricity. Until you turn the switch the electricity doesn't flow.
Now, the biggest difference between water and electricity is that water must flow within the pipe and electricity flows along the pipe (wire). This means that it can flow through the wire or along the outside of the wire. It only needs a means of conductivity. If a wire is cut or exposed, the electricity doesn't run out on the ground. If there isn't a conductor for the electricity, it stays right where it is. If someone touches the wire they can become "part of the wire". If that same person is grounded (touching something else that can be a conductor) then the electricity flows through them looking for ground. This is when you feel the shock.
If you are still with me, we can talk about a GFIC. A GFIC is a safety device that is designed to watch for electricity flowing where it shouldn't. In a properly wired house the electricity should flow from black (Hot) to white (neutral). If the GFIC senses electricity on the ground side instead of the neutral it opens the breaker to prevent the shock. This is why in the examples above, the pump continues to operate on a Non-GFIC outlet. Without a GFIC circuit, it doesn't care if the electricity finds a ground through the neutral bus or ground bus, just as long as it finds a ground. Your only protection at that point would be your normal circuit breaker, which is designed to open when it senses excess current (heat in most cases).
Now to answer your question...If your reef is setup on a GFIC circuit there is no stray current. The GFIC would sense the current and open. If you’re not on a GFIC circuit, buy one!!!!!!! It can be a lifesaver.
One final disclaimer. Some electrical devices that are inside your reef can produce very small electrical currents because they are magnetic in nature. They do have on the market an electrode that hangs in your tank and basically plugs into the ground hole of your outlet. This allows any electrical current to be discharged directly to ground. I have one. Really cheap. Don't really know if it is doing any good. I could hook a meter to the probe outside of the tank and let the other end of the probe dangle in the tank and I might see something. Not very likely though. Hope this helped a little. Feel free to ask follow-ups if you need. I am a pretty good electrician; probably a sorry teacher but I would sure give it a shot.

[Rick O]

Originally posted by Joel
So like a true reefer I took a bucket of water, put the pump in it, plugged it into a non gfci plug, and stuck my hand in the bucket. It didn't shock me and works fine.

Now that's dedication (or something else).

[Mkelly]

I am a pretty good electrician; probably a sorry teacher but I would sure give it a shot.

Ya done good