Hot/Ground reversed?

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I was asked to check out some receptacles that weren't working. Plugged in receptacle tester and the code for Hot and Ground reversed came up. Testing the home run I got 60v. The circuit is run in flex that has this thin non copper ground. Is this the reason it didn't trip the breaker or was there some kind of loop going on through the neutral?
 

ActionDave

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Testing the home run I got 60v. ....
60V to what, tested where?
The circuit is run in flex that has this thin non copper ground. Is this the reason it didn't trip the breaker
Sounds like AC cable. If it is terminated properly the combination of the sheathing and the strip act as an equipment ground.
or was there some kind of loop going on through the neutral
Don't know what you mean by this.
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
I have seen that on one of the small polarity testers I have. It lies :D When the circuit was actually checked, it was something other than "hot and ground reversed". Unfortunately I can;'t recall the specific "mis-wire"... I think open ground and neutral-hot reversed,
 

kwired

Electron manager
Location
NE Nebraska
I have seen that on one of the small polarity testers I have. It lies :D When the circuit was actually checked, it was something other than "hot and ground reversed". Unfortunately I can;'t recall the specific "mis-wire"... I think open ground and neutral-hot reversed,
I think I have had that happen before also. I think part of problem is these devices can not necessarily detect multiple errors in the connections. I remember one time having a failed GFCI causing readings on the tester that did not really make any sense, but can't remember for certain what the indication was or what the actual error was that the tester was seeing.
 
Well I'm not sure what a MWBC is, but no its just a circuit feeding counter top receptacles. The 60v is what was measured between hot and neutral so the problem isn't a reversed hot and neutral with an open ground. I'm going to replace circuit wiring.
 

John120/240

Senior Member
Location
Olathe, Kansas
Well I'm not sure what a MWBC is,

In residental MWBC is : two hots (red & black) one neutral (white) one ground (green). In a kitchen I would take a 12-3 w/G romex
to the fridge. Now add a 12-2 Romex that feeds counter top GFCI to your box. Both grounds pigtailed with a tail for the recptacle. Pigtail both whites w/a tail for recptacle. Red goes to the fridge recptacle. Blk in 12-3 pig tails to Blk in 12-2 to feed GFCI
 

kwired

Electron manager
Location
NE Nebraska
Well I'm not sure what a MWBC is, but no its just a circuit feeding counter top receptacles. The 60v is what was measured between hot and neutral so the problem isn't a reversed hot and neutral with an open ground. I'm going to replace circuit wiring.
Replacing circuit wiring is likely not necessary, finding the failed connection or device that is likely causing this problem is what you need to do first.
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
Well I'm not sure what a MWBC is, but no its just a circuit feeding counter top receptacles. The 60v is what was measured between hot and neutral so the problem isn't a reversed hot and neutral with an open ground. I'm going to replace circuit wiring.

Welcome to Mike holt!

I realize you are a young electrician , however if you are troubleshooting for hire i strongly suggest that you gain some more knowledge and skill. If you do not know some of the basics of home wireing you can wind up frying a customers property. You might even hurt yourself. That being said there are some great books out on the market that will demonstrate the basics in cluding a MWBC.
There was this book I picked up for a fresh aprentice once. It was thin and green. I can look for it if you want. The book covers much of the basics, Home wiring, farm wiring, motors , simple circuits, three way switching, it was a really good primer for those new to the field.

I also strongly advise looking into some online courses. There is lots of info at MH.

Enjoy
 

James S.

Senior Member
Location
Mesa, Arizona
I have seen that on one of the small polarity testers I have. It lies :D When the circuit was actually checked, it was something other than "hot and ground reversed". Unfortunately I can;'t recall the specific "mis-wire"... I think open ground and neutral-hot reversed,

I have definitely seen this before. I don't remember what the actual problem is either but can always diagnose it with a voltage meter right away. I don't think I have ever actually ran across an actual hot/ground reverse. It sounds like a simple loose neutral to me.
 

kwired

Electron manager
Location
NE Nebraska
60V to what, tested where?
Sounds like AC cable. If it is terminated properly the combination of the sheathing and the strip act as an equipment ground.
Don't know what you mean by this.

I appreciate any reference material suggestions but its obvious that I'm not the only on who didn't understand this one.

Some of us are still waiting for some answers before we will have a diagnosis. Back in post 3 you were asked "60V to what, tested where?" The answer to that question alone will dictate what question to ask next. Some of us more experienced troubleshooters don't understand yet either, but it is because of lack of information of what is there more so than not understanding what is going on.

You have to remember that those convenient three wire plug in testers have no idea what is true ground, they only can tell if each conductor is proper potential in relation to one another. If there is a good equipment grounding conductor their accuracy will be pretty good, if the equipment grounding conductor is compromised in any way you may get totally unexpected readings, even some that may seem impossible to someone with little troubleshooting experience.
 
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Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
Yea those three prong testers are only one of the tools we use to diagnose these issues. They help to move us in the correct direction but usually don't tell exactly what the problem is. From my desk and experience I would say problem nuetral. However I am sitting at my desk staring at a monitor with very little information as to your problem.
 

kwired

Electron manager
Location
NE Nebraska
If neutral and equipment ground are both connected to an ungrounded conductor and the "hot" is connected to a grounded conductor theoretically the plug in tester should read "correct" wiring. All the voltages will be in proper relation to each other, but the tester has no idea what true ground really is.

Could easily happen if there is a "bootlegged" ground from the neutral on a circuit that doesn't have an equipment grounding conductor, and the polarity of the branch circuit is reversed for any reason.
 

growler

Senior Member
Location
Atlanta,GA
I'm not the only on who didn't understand this one.

I admit I have no idea what's going on. Even if I was at the job I couldn't just go straight to the problem with the information given but I could trouble-shoot and find the probelm.

It's an old house with old wiring ( see it all the time ). Did you take the conductors loose at the panel and check continuity to see if say the hot and ground were shorted or the neutral and ground ( not all shorts are dead shorts that would trip a breaker )?

You say this is a circuit feeding the counter top. Experience tells me that back in the good old days when this house was wired there is no telling what all is on that circuit. When trouble-shooting forget all about code and what should be there and try to figure out what's really been done. Old houses are a trip and you can find all sorts of weird wiring. You trace the circuit and just see where it leads you.

A few years ago I had a problem it an upstairs bathroom and the circuit ran in PVC out through the back yard and had been damaged when they were grinding strumps. Not what I expected but that's where the problem lead me.


When you know you have a problem you follow it and find the cause.
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
I had a bug eye tester read hot & ground reversed. That was not the problem at all; it was a miswired GFCI recpt. Back in the old days you could put the line on the load terminals and the device would provide power without any ground fault protection.
 
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