How Do I Check for Stray Voltage??

kkgaskin90 · Jul 11, 2015

Talk to me like I'm clueless, because I am. I know I need a multimeter... One probe in the water and one to a good "ground". Set to DC, correct? Do I need a grounding probe in the tank as well? I read that if you aren't plugged in to a particular type of outlet that a grounding probe can become deadly? I just have a regular wall outlet. What are "acceptable" numbers?
I searched the forums and YouTube but I couldn't find anything that spelled it all out and I REALLY don't want to screw it up! Thanks!

kevinsmixed90 · Jul 11, 2015

you first look at your wall recept. where you plug things in. it should have three holes. two slotted ones and under or over those 1 round one. this is the ground. you then need to test for proper grounded outlet with a tester you can get from the hardware ( around five to ten bucks) it will tell you if you are properly grounded at the outlet. if you are you can get a ground probe that plugs directly into your wall recept. DO NOT plug one into a multi outlet unit! plug only into the wall. to test for stray voltage you will use the AC part of your multimeter turn the dial to the lowest test for AC presence.(200m or 2000m_ positive(red) probe goes into the tank or sump, and negative (black) to a known ground. should read zero. if you only have two slotted holes in the wall plug, the ground plug will need to be connected to a known house ground. if you do not know exactly how to do this get a electrician friend!! Always turn off breaker before checking behind wall recept. for a green screw (ground). hope this helps.

kkgaskin90 · Jul 11, 2015

Ok so how do I test that the outlet is properly grounded? Multimeter?

redfishbluefish · Jul 11, 2015

You're close. Using a multimeter/VOM set to AC Volts, put one probe in the water and the second on a good ground. I use either the ground plug in an outlet or the little screw on the cover plate of the outlet. That's it.

What's acceptable....well you will see some induced voltage from all the spinning things you have in the tank....for the sake of picking a number, I'll say 3 - 5 volts.

kkgaskin90 · Jul 11, 2015

redfishbluefish said:
You're close. Using a multimeter/VOM set to AC Volts, put one probe in the water and the second on a good ground. I use either the ground plug in an outlet or the little screw on the cover plate of the outlet. That's it.

What's acceptable....well you will see some induced voltage from all the spinning things you have in the tank....for the sake of picking a number, I'll say 3 - 5 volts.

So do I not need a titanium ground probe in the tank to check for voltage?

redfishbluefish · Jul 11, 2015

No. You actually want to unplug any grounding probes before checking for stray voltage.

In regard to first testing the outlet for proper ground, I have taken the leap of faith that the wiring in the home was properly installed and inspected. I'd have to believe the likelihood of a bad outlet is slim.

kkgaskin90 · Jul 11, 2015

Hubby has one for work, but has no idea how to use it. Which setting is AC?

kkgaskin90 · Jul 11, 2015

Heater gave off 4 volts. Skimmer 2-3 volts. JBJ ATO giving off 8 volts.
So now what?

redfishbluefish · Jul 11, 2015

kkgaskin90 said:
Hubby has one for work, but has no idea how to use it. Which setting is AC?

I guess you've figured it out.....You want the "V" with the squiggly line.....that's AC Volts. The V with the straight line and three dots is DC Volts.

kkgaskin90 · Jul 11, 2015

redfishbluefish said:
I guess you've figured it out.....You want the "V" with the squiggly line.....that's AC Volts. The V with the straight line and three dots is DC Volts.

Yup, got it

was the 3-5 volts total or per piece of equipment?

kkgaskin90 · Jul 11, 2015

I'm finding mixed opinions when I search... Replace the equipment or grounding probe to GFCI... The outlet is not currently a GFCI, nor is it easily accessible to work on.
That said, which is a better option? And if it's ground probe to GFCI, would this work?