Shocking... Multimeter help.

[FutureInterest]

Alright I got a lil shock when working in my tank last night. It was enough to make my whole arm tingle and that can't be good. I plugged in my grounding probe which wasn't plugged in but clearly I need to find out which pump/heater is leaking juice into the tank.

So I have a multimeter and I'm wondering what setting I should have it on when checking for current in the tank. Also one probe clearly goes in the tank and the other should be grounded I imagine. Do you just use a wall socket to ground it?

Thanks.

 

[derek_s]

Yes, put it on the current/amps setting and put one probe in the ground, and the other in the tank. It then should measure the current that will travel from the water to ground.

I would also remove the grounding probe until you find the problem. I dont have the link, but someone posted a really good article that I think was hosted by GATech that explained that if you ground the tank, the current can flow through, causing problems. If you do not have it grounded, the current cannot flow because of the open circuit, which is better. You felt the shock because you completed the circuit. The article was assuming you are on a GFCI circuit, BTW.

Maybe this is just a theory, but it made sence to me.

When I had that problem, I just unplugged teh heaters one at a time and put my paw back in. Maybe a masacistic way of doing it, but I found the culprit.

 

[budsreef]

Jin, if it was me, I'd check for voltage first. One lead in the tank and one in the ground.

 

[derek_s]

You can check for voltage, but saltwater will always show a difference of potential, wont it? Even SW without any electrical devices? Something about the caustic/alkaline properties (think alkaline battery).

I am not telling, I am asking, BTW.

If so, what is an acceptable voltage and what is not?

 

[stacy22]

Derek maybe you should go to Jin's and keep sticking your arm in his tank until you guys figure it out.

 

[derek_s]

I like that idea. But I cannot be held responsible for electrical shocks that trigger muscle spasms that cause uncontrollable clenching of coral colonies.

 

[rostato]

I would just cjeck for voltage. In order to have some amperage flowing around you will need some voltage too. Plus if it just tingled then there is not going to be much amperage going through the tank, and your meter may not pick it up.

Once you get a reading just unplug one thing at a time untill your reading lowers, or goes away.:thumbs:

 

[linda lee]

I'd like some popcorn and a ringside seat, please.

 

[molson]

Jin - I assume this means that I have to remove the coco worm myself? If so I'll bring PLASTIC tongs and up my life insurance lol.

 

[crew]

hahaha maybe not fun, but it is funny

 

[molson]

ares;283670 wrote: if you gotta put your hand in the tank, just wear some sneakers, and dont touch the wall.

till you get it fixed anyway.

So does that make it something like a aquatic version of "Operation"?

 

[fishgardener]

Jin,
Blake is having the same problem. He unplugged his Stealth heater and problem gone! The heater is less than a year old. Of course his system is way smaller than yours so there are a lot fewer potential causes.
Sheryle

 

[dannybradley]

When testing for DC current you ground, and AC current you complete the circuit between hot(tank) and neutral(larger slit on the socket). Am I correct with this? When testing AC current in tanks, I cannot get a reading by grounding the probe.

I would use the volts setting, Jin. Also, screws on a external pump can trasmit voltage to the tank via salt creep. The pump housing is coated and will not.

 

[FutureInterest]

Thanks for your help guys. It turns out it was one of my 3 stealth heaters. It's less than 6 months old too :sad:.

Thanks again!

 

[drnecropolis]

Atleast you found out what it was..

 

[chicagoman_35]

Yea, check voltage... Odds are your multimeter won't see the low current, esp being ac current. It would be in the milliamp range.