UPS indicates ground fault :\

[Diablo]

Got my UPS not too long ago, plugged it in, & a red light comes on indicating a ground fault. Tried other outlets in my room & got same result. Its an older house, so I'm really not surprised.

'Till i get the house rewired, will it be safe to continue using the UPS? Just worrying about possible damage to my UPS and/or hardware

[DoPeY5007]

I say gut the house fixed ASAP.

I am not sure what kinda damage can be done with out!

[sho.gun]

but before that I suggest you visit your neighbor's house and try it out, maybe its just a faulty ups...

[Diablo]

It's definately the wiring & not the UPS, i made sure of that. Basically what i'm asking is, 'till i get the house rewired, what would i be better of with - the UPS or a surge protector ..wasnt sure if this prob could potentially damage the UPS or not.

[CluelessSi]

Originally posted by DarkFury

Why don't you reverse the polarity of the wires in your room?


I had the exact same problem when I first moved into my house. But the fix to the problem is the shut off the power from the main, take the electrical cover off and switch the positive and negative poles on the electrical outlet... thus reversing the polarity and correcting the line fault.

As long as you cut the power to the room, you shouldn't have any problems in doing this. Good luck. :thumbup:


hmmm.... are u sure that is a correct fix to the problem? I am not sure if you should sweitch the polatiry when the circuits usually have a bigger and smaller prong (unless three headed w/ground) so that you are using the correct pola\rity. What causes the ground fault anyway? I would call UPS up and ask if it was safe to plug it in

[smurphy]

I have a 48+ year old house that also indicated a ground wiring fault. I consulted several electrical stores and a couple of electricians and they said to simply turn my power off and take a copper wire, minimum of 14 gauge solid copper wire (not electrical cord) and connect it to the power outlet with a screw to the back of the electrical outlet box that the outlet connects too. You should upgrade to newer outlet if it does not have a ground wire connector. This is not a perfect ground but will do the job. If you own the house you should start to upgrade the wiring, fairly easy if you have an unfinished basement, I have only my dining room left. If you are renting, you should talk to the landlord to get the place up to code. Also I have to mention don't do this with the power still on.......

Cheers,
Scott

[LPMiller]

it's a good possibility your house isn't grounded as many older homes are not.

You can live without grounding. First, use the UPS - it will offer up some protection, tis what it does. Second, kill the power and change you outlets for GFIC outlets. These will cut the power at the outlet in case of trouble, and are recommended in place of grounding for added protection. It's not quite as good as grounding, but might be the best you can do till you get the place rewired.

Most electricians will tell you not to replace older wiring unless you have to - it's rather expensive, and not necessarily worth the added cost...especially if they have to upgrade the junction box to accept grounding, or if the older wire is in tightly packed walls.

Chances are you'll find many outlets wired funky, they did things differently back in the day.

Just some of the joys of an older house.

[i6s1]

Originally posted by CluelessSi


What causes the ground fault anyway?

These are slightly educated guesses as to what the UPS engineers would put in to cause a ground fault:

-Resistance between the ground and the neutral is 0, indicating the quick fix that smurphy described.

-Resistance between the ground and neutral and/or hot is too high, indicating a bad or nonexistant ground. (like the ground spike got pulled out of the dirt)

-voltage between the neutral and ground is not zero, indicating DF's problem of hot/neutral switch. (Not a positive and negitive switch as he described, there is no positive and negative in an outlet.)

There could be more reasons, or these could be wrong.

[i6s1]

Yeah, you should be able to diagnose the hot/neutral problem yourself. Take a voltmeter. Turn it to the 120+VAC range. Plug the probes into the neutral and the ground. You should get 0. If you get 120, they're switched. Kill the power to the room and check all 3 hot/ground, neut/ground/ and hot/neut to verify it's safe. Then take it apart and switch it.

[Diablo]

The outlet(s) in my room are older 2 prong and i used a grounding adapter between the outlet & the UPS. I looked beneath the electrical cover & did see a grounding wire. I connected the grounding adapter to the outlet w/ a screw (as smurphy said). Still getting a grounding fault.



Originally posted by DarkFury
Note: Improper building wiring will not prevent the Back-UPS from operating, but it will limit its protection capability. It may also result in equipment damage that is not covered by the APC Equipment Protection Policy.

I guess that pretty much answers my question...the UPS' protection capability will be limited, but the UPS (or my equipment) will not be harmed as a result of the older warning. At the very least, I'm better off w/ the UPS than w/o. Are my assumptions correct? :hmm:

[LPMiller]

Originally posted by Diablo
The outlet(s) in my room are older 2 prong and i used a grounding adapter between the outlet & the UPS. I looked beneath the electrical cover & did see a grounding wire. I connected the grounding adapter to the outlet w/ a screw (as smurphy said). Still getting a grounding fault.


Because it isn't grounded. 2 prongs aren't grounded at all. Hence the fault. Add a GFIC, and if you can, a ground wire from the outlet to the metal box. May or may not get the UPS to say things are ok, but it will give added protection. Yes, GFIC's are required to be used around water, but are also suggested where grounding isn't possible/feasible. You may find it real easy to add the ground wire though, depends on the circuit route.

[LPMiller]

Originally posted by DarkFury

Personally... I'd call a professional electrician to look at the wiring in that one room... It might be worth it to fix that one room rather than re-wire the whole house.

Good luck getting your electrical woes solved...

Actually, if it's like my house, that likely won't be much cheaper. 50 year old homes tended to have many rooms on the same circuit, in one continuious wire. Likely, he'd have to uprade the junction box, and split that room off on it's own circuit.

[LPMiller]

Yeah, I was lucky too - I have a normal circuit box, and half my house is grounded. The other half still uses the old wiring, and all the bedrooms, the living room and the entire basement is on 1 15amp circuit,which I blow all the time. I need to split the basement off on it's own circuit, but haven't gotten the gumption up to do it.

[i6s1]

There may be wiring that can't handle more then 15 amps. Usually its fine because they work in quite a bit of a safety margin.

[LPMiller]

I don't trust the wiring to take 20 amps. I mean, it's 53 years old.