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Recepticle Tester reads "Hot/Neutral Reverse" with cover plate on

Recepticle Tester reads "Hot/Neutral Reverse" with cover plate on


  #1  
Old 02-17-03, 05:40 AM
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Recepticle Tester reads "Hot/Neutral Reverse" with cover plate on

Guys,

I'm nearing the end of putting on the finishing touches on the electrical updates of my 1949 cape cod. Roughly half of of the 3-prong recepticles did not have ground wires, which I've added in all but two rooms.

So I pop my handy circuit tester into one of them and get the "Hot/Neutral Reverse." So I pull the cover off and see black and wires coming in and out of the upstream and downstream ends of the recepticle. Before I throw the breaker to switch the wires, I pop the tester in again and get "Open Ground," as there is no ground wire.

Then I reattach the recepticle to the box, put the cover back on, and get the Hot/Neutral Reverse again.

I could easily ground this thing as I've got a grounded recepticle nearby, but I'd like to resolve the test error first. Any ideas as to what's going on here would be appreciated.

Oh, and the recepticle was installed upside down.
 
  #2  
Old 02-17-03, 06:23 AM
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Hot/ground reverse is almost always a false indication for open neutral. I shutter to think of people who might actually be reversing their hot and ground after getting this reading.

If you shut off all switches on this circuit, and unplug everything plugged into it, you will correctly get the open neutral reading.

You also seem to have a problem with an inadequate grounding connection. I am quite concerned about your adding grounds. Exactly how did you do this?

P.S. There is no such thing as an upside down receptacle.
 
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Old 02-17-03, 07:44 AM
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John,

On the Hot/Neutral (it wasn't the Hot/Ground reverse warning), so the reading was a result of having something plugged in and turned on in the recepticle downstream of the one I tested? Or is there an issue with the netural wire?

I appreciate your inquiry on grounding. I haven't been connecting to water pipes or anything like that, I've been running 12-gauge green wires back to the panel. In one instance, I did replace the old romex with 12/2 AC. As much as I'd prefer to replace all of the wiring with new AC, I've seen the massive staples they used to put the old copper in the house, and I would be fishing for days.

This particular recepticle has some old BX/AC running all the way back to the panel. The wire and insulation is in pretty good shape. I suppose there's a chance I could ground to the cable, but I'd feel better about a green wire.

Since I have your attention, the recepticle sits above a green wire (running in the basement joist space) I've already run from a different recepticle. Can I splice into this wire (with a junction box and wirenut, obviously), or should I give it its own run to the panel?

Please call me out on this if I've endangenerd my home, computer, self, etc. via this method of grounding.
 
  #4  
Old 02-17-03, 09:38 AM
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Oops, sorry. I misread. Ignore all my previous remarks.

Hot/neutral reverse indications are usually exactly what they say -- the hot and neutral are reversed. And the solution is to reverse them back. But you should test all receptacles on the circuit first. If there are multiple receptacles with this same problem, you can fix the first place where they were messed up and thereby correct them all at once.

Your question about whether or not you can tie into an existing grounding wire was the subject of a long and intense and never satifactorily resolved debate in this forum a few months ago. I'd prefer not to reopen that can of worms.
 
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Old 02-17-03, 10:21 AM
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John,

So if flipping the Hot and Neutral will solve the problem when the recepticle is attached to the junction box and with the cover on, what will happen when the cover's off? My tester read "Open ground" as it should when I had the cover off?

I'll test this again tonight, but I doubt I was seeing things yesterday.

Boy oh boy was the discussion on tying into an existing ground some good reading. I'll take the extra 10 minutes and go to the panel.
 
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Old 02-17-03, 10:34 AM
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What do you mean by "cover off"? The cover should have no effect on the readings you get from that outlet. If you actually mean to say that you remove (unscre) the outlet from the box, then you will get an open neutral if you have metal boxes and the grounding is provided by the actual mounting screws (i.e. no green bonding jumper between the metal box and the grounding screw on the outlet. If the wires are the correct color (white to silver, black to gold) at this outlet, then I would look for what's feeding this outlet, and solve it there.
You may not need a "grounding wire" if you have flexible metal conduit (BX). You may not even need that green bonding jumper, but I've been told conflicting things about that.
I do know that you can't just add a separate ground wire to a line ( i.e. tape it), it has to be part of the wire, or in the same conduit).
 
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Old 02-17-03, 01:30 PM
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Actually, you can add a separate grounding wire in a retrofit situation.
 
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Old 02-17-03, 02:00 PM
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I think Trinitro has correctly diagnosed the situation. The old AC could be serving as a ground and just needs to be tied into the recepticle. I hope he's right as that would save time and green wire (Dad bought me a big roll and fish tape as a housewarming present).

I'll look into this on Wednesday and let you guys know what happens. Thanks.
 
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Old 02-19-03, 07:25 AM
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The saga continues.

Turns out Trinitro was right, I do have a ground at the box (probe tester confirmed this). A short jumper and I'm done.

Still got the "Hot/Neutral Reverse" on my recepticle tester. I think whoever installed this outlet ground plug up just lapsed and forgot which side is hot.

Can you guys give me a recommendation on getting the wires out of backstab connections? I loosened the screws all the way, and they still didn't want to budge. I could cut the wires at the connection and put in a new recepticle, but I'm concerned I'll be a little short on wire in the box.

Here's what I also discovered:

1) Nothing upstream reads Hot/Neutral reverse.

2) Nothing downstream reads Hot/Neutral reverse.

If I swap the hot and neutrals here, will I be reversing this for the downstream ones?
 
  #10  
Old 02-19-03, 10:50 AM
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The black wires should be on the gold screw and white wires on the silver screw. If not then you do indeed have them reversed. If you are concerned about the wires being short if you cut them SMASH the receptacle and get the wires out. The back stabs are very common causes of problems any way. Replace the receptacle with new one that has screw connections.
 
  #11  
Old 02-19-03, 11:08 AM
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There are small release holes on the back of the receptacle. Push a paperclip or small screwdriver in this hole and the backstab will release.
 
 

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