Electricians, Step Inside, Please. Polarity Question.

[Beau Cassidy]

I am in the process of buying a new place to cast boolits. During the house inspection last week the inspector who seemed to really know his stuff, made mention of reverse polarity on 6 or 7 electrical outlets in the master bedroom. I pulled all of the covers and looked at the wires. They all look to be hooked up correctly with the black wires going in the black side of the outlet and the white wires going into the white side of the socket. All had grounds, too. I am at a loss here. Could the inspector have done something wrong?

Beau

[elk hunter]

I'm certainly not an electrician, but do have some knowledge and experience with electricity. Could be that the hot and neutral wires have been swapped at another inline outlet or fixture further up the line towards the breaker for the circuit. I would backtrack the circuit and look for an owner installed light or outlet.

[C.F.Plinker]

Go to the hardware store or home center and get a polarity checker. It looks like a 3 wire plug but it has 3 little neon bulbs in it. When you plug it into the outlet, two of the three should light up. Referrring to a decal on it, you can tell if the outlet is wired correctly, and, if not, what the problem is.

The black wires should come in to and leave the side of the outlet with the shorter slot for the blade of the plug that goes into it. The white wire should come into and leave the side with the taller slot.

Since one of the outlets is wired correctly, I would look closely at that one and make sure that the black and white are connected correctly and that there are no connections inside the outlet box where a black wire is connected to a white wire or where both colors come into the same side of the outlet. If you are going to loosen the outlet and pull it partway or completely out of the box go out to the panel and open the breaker feeding these outlets. While you are looking inside the box make sure that the green wires are not connected to any other color of wire.

IF YOU ARE NOT COMFORTABLE DOING THIS YOURSELF, GET AN ELECTRICIAN TO DO IT FOR YOU. Electricity does not forgive any type of mistake.

[GRUMPA]

I've never heard of that before....???? just for grins just like already said one of those polarity checkers will make short work of it. And Plinker has that explanation well said.

[MT Gianni]

If you are the buyer tell the homeowner to fix it as a condition of sale. Option two is for the homeowner to get two estimates and knock the lower off the price of the home if you wish to do it yourself. If the estimates differ by more that $50 find out why. IMO you should not offer to solve sellers problems or they will assume that you can solve all problems and there is no need to inform you of anything else. If you are related then you might cut them some slack.

[BeeMan]

Don't count on wire color. For less than $10 you should be able to pick up a simple diagnostic tool at your local home improvement store. It has a grounded plug and several indicators to show whether the outlet being tested is wired correctly or has a specific wiring fault.

I'm not an electrician, but a couple of the houses we bought had 'special' wiring. The tester I have is an IDEAL Analog Multimeter GFCI Receptacle Tester.

BeeMan

ETA: Gianni makes a good point about not solving the seller's problem.

[Jammer Six]

The qualifications to become a gunsmith and the qualifications to become a home inspector are identical.

[Catshooter]

Well, I am an electrician (34 years) and for once you've gotten good advice.

The white wires connect to the sliver colored screw, black to the brass colored.

The problem probably won't be with the ones that test bad, rather it more likely lies with the one that feeds those. Open it up and you'll find the two wires that are swapped. That will likely fix all the rest.


Cat

[Lee]

Could be switched outlets? Lazy people don't always re-color the wires when making up switched outlets.

Only "trick" I've ever heard of is turning an old 2 wire outlet into a 3 wire outlet. Wire the ground wire together with the white wire. That will fool the common electrical tester, but that is not an accepted method. I don't know if that kind of bubba wiring would support a GFI receptacle. Never tried it, don't intend to.
Other than that, it still sounds like a case of reversed/switched wires in the receptacle boxes. Should be an easy fix in any case.

[runfiverun]

like cat said because the plugs are correct don't mean the wires are hooked up at the box correctly.
or havent been swapped in a junction box.

[jsizemore]

Just like Cat said. Since they are are all PROBABLY on the same circuit and are in a line one after the other, your MOST LIKELY candidates are the ones that read incorrect at either end of the line OR the ones just proceding those that read correctly. If not you'll have to check each individual outlet. Since it's a master bedroom some of half the outlets may be controlled by a switch for a lamp.

[odfairfaxsub]

I don't know if that kind of bubba wiring would support a GFI receptacle. Never tried it, don't intend to.

not likely, (ibew lu 50) you can actually trip the gfi as a way to trip the circuit behind you with the gfi outlet itself by touching the neutral and ground together.

[Dale in Louisiana]

Please be careful.

Unusual for an on-line forum, this is all pretty good advice. As a long-time electrical guy (up to 500,000 volts) I can tell you GET the 'polarity tester'. Should be available at Lowes, Home Depot, Radio Shack or most good lumber yards. Using it is self explanatory.

It is not unusual on homes that have been subject to owner 'repairs' and 'modifications' to find things crossed up, because many people don't understand the need for correct orientation of hot, neutral and ground.

that said, if you find a receptacle that shows incorrect polarity with the tester, make sure you turn off the breaker that feeds that receptacle before you go messing with it with the cover off. 120 volts kills MORE people every year, because "That's just one-twenty! ANYBODY can work on it!"

Adn despite all the wonderful advice here (including mine) if you're the least, tiniest bit unsure about what you're doing, get competent help.

dale in Louisiana

[Bret4207]

Well, I am an electrician (34 years) and for once you've gotten good advice.

The white wires connect to the sliver colored screw, black to the brass colored.

The problem probably won't be with the ones that test bad, rather it more likely lies with the one that feeds those. Open it up and you'll find the two wires that are swapped. That will likely fix all the rest.


Cat

Holy krap! You mean I guessed and did it right???!!!! The only way I could remember stuff was that black and brass were darker than silver and white and black and electricity always reminded me of The Black Death so that made sense since the black was the hot wire that would pass gazillions of volts through my body seeking ground. Of course that's just the opposite of auto electricals where black was always ground and white or red was hot.

Got one of those polarity checkers some years back and fixed a lot of mistakes in our house. They (Ideal) also make one for you phone jacks that's real handy when the phone goes dead.

[odfairfaxsub]

that tester is generally what home inspectors will base 99 percent of their decisions on a final insp.

[Blacksmith]

One more caution. Just because the outlets are in the same room and all in a line DO NOT ASSUME they are all on the same breaker. Test each outlet top and bottom to make sure all the necessary breakers are off before working on them. Don't ask how I know.

[Jammer Six]

I was a general contractor for twenty years. (More or less, depending on how you count.) I inspected homes for about four of those years, but I got tired of being lumped with used car salesmen. And I saw their point-- I never met an inspector with a very high skill level.

Electricity is a powerful magic force controlled by wizards called "electricians". Do not anger the lords of electricity, lest blue flame leap across the basement and smite thee.

There's something about multiplying, and a hose, and gallons of water and the water pressure and the number of lightbulbs in a circle.

I have my electrical sub on speed dial. When he wants a giggle, he tries to explain it all to me. Again.

We have now reached the limits of my knowledge about electricity.

[geargnasher]

Holy krap! You mean I guessed and did it right???!!!! The only way I could remember stuff was that black and brass were darker than silver and white and black and electricity always reminded me of The Black Death so that made sense since the black was the hot wire that would pass gazillions of volts through my body seeking ground. Of course that's just the opposite of auto electricals where black was always ground and white or red was hot.

Got one of those polarity checkers some years back and fixed a lot of mistakes in our house. They (Ideal) also make one for you phone jacks that's real handy when the phone goes dead.

Wanna REALLY get screwed up? Work on RVs all day, where the standard 12VDC coding is black wire=ground, white wire = positive, then come home and do house wiring where white is neutral and black is HOT! Grrrrrrrr.

I'm guessing sombody replaced an outlet at some point and got the wires swapped, so the remainder of the string has reversed polarity.

Gear

[JeffinNZ]

What I want to know is to be an electrician do you have to be bi-polar.......?

[odfairfaxsub]

lol silly jeffinnz. no but at least half on the job have to be cocky sexist individuals and atleast 3/4 must use some kind of tobacco product.