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ATOT Electricians

AmdEmAll

AmdEmAll

Diamond Member
I have two APC Surge Arrest personal surge protectors plugged into two different outlets in the same room.. same circuit breaker and I just noticed one of them has the red light on saying "site wiring fault".

Now I don't know if it was always on like that and I didn't notice it or it just came on recently. The wiring in the house was all redone a couple years ago.

It looks like this:
http://www.uneekcomputer.com/images/APC-PER7-Personal-Surge-Arrest-Protector-7-Outlets-0.jpg

My first thought was maybe the outlet is bad so I replaced it and the wiring looked fine.. ground white and black were going to the right spots.

The new outlet didn't fix anything.. so im not sure what would cause this.

If I plug this surge protector into any of the other outlets the red light goes off.

Also my electrical tester lights up when I put the pins in either ground or the upper two plugs so it appears grounded..
 
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Phoenix86 said:
The outlet with the red light doesn't have a ground.
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THis. If you can determine where the line is coming FROM, I'm betting the other end doesn't have a ground connected. Might be hard to figure out though but it is probably daisy chained off of another outlet in the room.
 
TwiceOver said:
THis. If you can determine where the line is coming FROM, I'm betting the other end doesn't have a ground connected. Might be hard to figure out though but it is probably daisy chained off of another outlet in the room.
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But 3rd prong is ground right? My tester lights up when I touch it

APC says this on their site

Reasons why the Site Wiring LED light will illuminate:

1. Overloaded neutral wire.

2. Reversed polarity (hot and neutral wires are reversed).

3. Missing ground wire.

How does #1 happen?
 
#1 is probably too much current flowing from the hot wire to the cold wire (or too much resistance on the cold wire). It seems unlikely.

#2 seems very likely. I've frequently wired this wrong, because some idiot decided to make the "hot" wire black and the "cold" wire red, even though this is the opposite of the way black body radiation works. (Red hot is hot!)
 
Black is hot because black stands for death, as in do not touch. Or at least it's a good way to remember it. White is neutral. White is the color of peace usually. White dove, flag, etc.

Insert racist joke here: ________________________.
 
#1 happens when novices try to same time and money by 3 wire plus ground cable and using the white as a common neutral while using the red and black as 2 separate 120v circuits, thereby doubling the load on the neutral.
 
Well there is no red. Just white, black, green. The white and black are plugged into the proper connections on the outlet but maybe they are reversed somehow where they daisy chain? How can I check this with a multimeter?
 
Micrornd said:
#1 happens when novices try to same time and money by 3 wire plus ground cable and using the white as a common neutral while using the red and black as 2 separate 120v circuits, thereby doubling the load on the neutral.
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Um no, that is allowed, even in single phase. As long as you don't have the hots landed on the same phase. You can even use three hots with one neutral if you are on a 3 phase (very uncommon in residential) and each hot is on a separate phase.

OP, have you measured voltage from neutral to ground, or were you doing a continuity test? If you get voltage from neutral to ground then you more than likely have a loose neutral somewhere. The higher the voltage, then usually it is closer to the panel, you are essentially reading the voltage induced in the neutral running alongside a hot wire.

Ken g6 said:
#1 is probably too much current flowing from the hot wire to the cold wire (or too much resistance on the cold wire). It seems unlikely.

#2 seems very likely. I've frequently wired this wrong, because some idiot decided to make the "hot" wire black and the "cold" wire red, even though this is the opposite of the way black body radiation works. (Red hot is hot!)
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That "idiot" was probably a licensed electrician, because black is always the hot wire in AC wiring. The "cold" (neutral, BTW) wire is usually white, and red is another phase of hot, or sometimes used as a switch leg.
Edit: Reread that and yeah it is irresponsible to use a red wire as neutral without taping it white.

AmdEmAll said:
Well there is no red. Just white, black, green. The white and black are plugged into the proper connections on the outlet but maybe they are reversed somehow where they daisy chain? How can I check this with a multimeter?
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Check voltage to ground on both of them. Another thing to try is run an extension cord from a plug that does work and use the continuity test on your meter to the ground pins on the extension cord and receptacle that is giving you trouble.
 
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AmdEmAll said:
Thought I brought my multimeter when I moved but I guess I left it.. may have to get one of those.

What about one of these?

http://www.amazon.com/Sperry-Instrum...=outlet+tester
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That will work for basic diagnosis, but you won't be able to investigate what that tool tells you without a proper multi-meter. Harbor Freight nearby?

That one will tell you all you need to know, and is cheap, but don't expect it to last very long.

Edit: Scratch that, the AC range is unusable on that one, you would want something like this to track down a loose neutral. Does the receptacle work normally otherwise?
 
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Captain Howdy said:
That will work for basic diagnosis, but you won't be able to investigate what that tool tells you without a proper multi-meter. Harbor Freight nearby?

That one will tell you all you need to know, and is cheap, but don't expect it to last very long.

Edit: Scratch that, the AC range is unusable on that one, you would want something like this to track down a loose neutral. Does the receptacle work normally otherwise?
Click to expand...


Thanks for the link and yes it seems to work fine other than the light. My pc was on that outlet.. I moved it now since I don't know if its safe.
 
AmdEmAll said:
Thanks for the link and yes it seems to work fine other than the light. My pc was on that outlet.. I moved it now since I don't know if its safe.
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Well that rules out loose neutral. And you said you had a green insulated wire in your box? That is rare in residential applications (I'm a commercial electrician and used to seeing them) as they are usually bare copper in a romex jacket. Is the box you are dealing with plastic?

My guess is that a ground was forgotten about somewhere along the line, but again, JBoxes are uncommon in residential applications and most home runs either go straight to the panel or are simply jumpered from device box to device box.
 
Captain Howdy said:
Well that rules out loose neutral. And you said you had a green insulated wire in your box? That is rare in residential applications (I'm a commercial electrician and used to seeing them) as they are usually bare copper in a romex jacket. Is the box you are dealing with plastic?

My guess is that a ground was forgotten about somewhere along the line, but again, JBoxes are uncommon in residential applications and most home runs either go straight to the panel or are simply jumpered from device box to device box.
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Just looked at it again and yes the ground is a green wire. The box is metal. Green wire runs to where the white and black come from. Don't know if this is relevant but my test light comes on when I touch the ground/hot and metal box/hot.
 
AmdEmAll said:
Just looked at it again and yes the ground is a green wire. The box is metal. Green wire runs to where the white and black come from. Don't know if this is relevant but my test light comes on when I touch the ground/hot and metal box/hot.
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Is there a bonding screw in the box? A ground pigtail? Seems like the box is properly grounded and you might get lucky enough to attach a pigtail from the box to your green wire and then a jumper to the grounding screw of the receptacle.
 
In those 3 pics what I see is that there are Hot (Black) and Neutral (White leads entering the box and attached to the correct outlet terminals. HOWEVER, although there is a green wire connecting the Ground terminal of the outlet to the box, I see NO Ground lead entering the box. Now, you say there is a voltage between Hot and Box, and that indicates that there is SOME Ground connection to the box. Maybe it is via conduit - I cannot tell whether that is a conduit fitting entering the box from the bottom, or just a clamp for common cable. But my guess is that the quality of the Ground connection to this box is poor - that is, its resistance to real Ground is too high - and that is what your warning light is telling you. The fact that there is a measurable voltage from Hot to Box is not a good enough test to determine whether the box has a low enough resistance to true Ground.
 
Paperdoc said:
In those 3 pics what I see is that there are Hot (Black) and Neutral (White leads entering the box and attached to the correct outlet terminals. HOWEVER, although there is a green wire connecting the Ground terminal of the outlet to the box, I see NO Ground lead entering the box. Now, you say there is a voltage between Hot and Box, and that indicates that there is SOME Ground connection to the box. Maybe it is via conduit - I cannot tell whether that is a conduit fitting entering the box from the bottom, or just a clamp for common cable. But my guess is that the quality of the Ground connection to this box is poor - that is, its resistance to real Ground is too high - and that is what your warning light is telling you. The fact that there is a measurable voltage from Hot to Box is not a good enough test to determine whether the box has a low enough resistance to true Ground.
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Abridged, clarified, and simplified version:

We see a wire from the box to the outlet (green). There should be another wire tied to the box (either green, or bare) that leads back into the wall. Otherwise that box is just floating and isn't really grounded.
 
Pulsar said:
Abridged, clarified, and simplified version:

We see a wire from the box to the outlet (green). There should be another wire tied to the box (either green, or bare) that leads back into the wall. Otherwise that box is just floating and isn't really grounded.
Click to expand...

I see.. so does an electrician needs to be called out then? Can the outlet be used safely or its not?
 
AmdEmAll said:
I see.. so does an electrician needs to be called out then? Can the outlet be used safely or its not?
Click to expand...

It's nothing earthshaking. You just need to find out if the box is really grounded. Look around it / behind it. Find that third wire (green or bare) that should be with the other two.
 
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