How Do I Test For Overloaded Neutral Wire? APC J15

[Anonymous user]

I have a J15 A/V and the Building Wiring Fault light is illuminated. I bought a circuit tester and it checks OK for reverse polarity and missing ground wire. But it cannot test for an overloaded neutral wire. I have a multi-meter, but how do I test the outlet for an overloaded neutral? Do I just stick one needle in the ground socket and another needle in either the positive or negative socket and see if I get a reading >5 volts? Also, I'm not even sure what level to set the multi-meter either.

The J15 Building Wiring Fault light will illuminate for the following reasons:

Overloaded neutral wire (>5vdc measured between Neutral and Ground);
Reversed polarity (hot and neutral wires are reversed);
Missing ground wire. (Note: this also includes using a 3 prong to 2 prong adapter).

[BillP]

Hello Howard,

You need to measure the voltage between the Neutral and ground. If you find that teh coltage is more than 5 Volts then it indicates that the neutral is over loaded.

Thank you!

[Anonymous user · Accepted solution]

Thanks. It turns out that I get readings of 1V max. Turns out that all my tests passed, yet the J15 still has a Building Wiring Fault. I'm not happy with APC right now.

Message was edited by: a_ok2me

Message was edited by: a_ok2me

[BillP]

Make sure you change the measurement mode on the voltmeter to AC, too - not DC.

[voidstar_apc]

>
Also, the multimeter is set for 200VAC
but it is a 120VAC circuit. I would recommend changing the setting to
the 150VAC setting.
>

200VAC is a good setting. The picture's blurry, but in another you can see that the other setting is 750VAC... ie, there's no 150VAC setting.

[Anonymous user]

a_ok2me,

i don't have a j15 but rather a h15. i had the same problem you're having. bad wiring ok light.

i sent them an e-mail through their system and got the issue resolved in 1 day. i tried everything they say to do in the manual just like you did.

i told them that and they told me that some units were shipped with wiring ok lights that were not working. why? who knows? anyways, they said they're going to ship me a new unit at no charge and i get to keep the old one. fwiw, she said the unit is still providing protection but just the light doesn't work. it may be the case for you as well. i'd tried doing the same thing.

[Anonymous user]

I have a J15 A/V and the Building Wiring Fault light is illuminated. I bought a circuit tester and it checks OK for reverse polarity and missing ground wire. But it cannot test for an overloaded neutral wire. I have a multi-meter, but how do I test the outlet for an overloaded neutral? Do I just stick one needle in the ground socket and another needle in either the positive or negative socket and see if I get a reading >5 volts? Also, I'm not even sure what level to set the multi-meter either.

The J15 Building Wiring Fault light will illuminate for the following reasons:

Overloaded neutral wire (>5vdc measured between Neutral and Ground);
Reversed polarity (hot and neutral wires are reversed);
Missing ground wire. (Note: this also includes using a 3 prong to 2 prong adapter).