Outlets wired backwards

[Tdog]

What are the consequences, dangers, problems that result from using outlets with neutral and hot reversed? All my outlets are wired that way. I've been redoing them, but haven't felt much urgency since the outlet works. It is a simple task to correct, except the house was built using 10 gage wire - - between the stiff wire & my arthritis, it is no fun.

Thanks,

Jack

 

[JB4310]

Little more info needed, first off how are you sure they are backwards?
Are they polarized outlets, with one slot bigger than the other?
Are they grounded outlets, with the round ground prong hole?
Are they 20 amp outlets, where one of the slots is t shaped?
What size breakers are protecting these receptacles, 15 or 20 amp?

Having 10 ga wire is strange, not sure if that's a safety concern by itself, as long as the breaker is not rated higher than the wire or receptacle.

As far as having neutral and hot reversed, not sure about electronics, but some appliances and lamps can pose a higher shock hazard, from what I understand.

JB.

 

[biggerten]

What are the consequences, dangers, problems that result from using outlets with neutral and hot reversed? All my outlets are wired that way. I've been redoing them, but haven't felt much urgency since the outlet works. It is a simple task to correct, except the house was built using 10 gage wire - - between the stiff wire & my arthritis, it is no fun.

Thanks,

Jack

Well, let's see. Someone needs to use a piece of equipment that requires the ground (has three prongs). They also need an extension cord, and only have one with the two prong receptacle. They know it will still work if they cut off the un-needed third prong, so they do so. They do not know that the outlet is wired backwards (and think it will be OK, even if they did). Now, the tool (or whatever) can malfunction, the protective ground won't be there, the outlet is wired backwards and the tool's enclosure is now electrically hot. Death is a possibility.

Fix the outlets. Oh yeah, never cut off that un-needed prong, at some unfortunate moment you (or someone you care about) WILL need it.

 

[dave1949]

Just a sanity check: white (neutral) on silver colored screw and black (hot) on brass/copper colored screw.

 

[beenthere]

Hope you get them corrected.

This is why people push for building inspectors, I'm sorry to say.

 

[MikePA]

What are the consequences, dangers, problems that result from using outlets with neutral and hot reversed? All my outlets are wired that way. I've been redoing them, but haven't felt much urgency since the outlet works. It is a simple task to correct, except the house was built using 10 gage wire - - between the stiff wire & my arthritis, it is no fun.

How are the circuits wired at the panel, i.e., did they reverse the white and black there too?

It's hard to believe a licensed electrician reversed the white and black and used 10 gauge wire.

 

[Tdog]

Geez guys - - they are backwards. I plug the tester in & it tells me the common & hot are reversed. I shut off a breaker, pull the outlet & take a look. Sure enough the black is wired to the side that says 'white'. Pretty stupid, but consistant throughout the house. As i said, it is hard for me to do physically, but I'm plugging away at it.

I would still like to know the consequences of usuing the outlet with the common/hot wires switched. No one is cutting off ground prongs - - but I see what bigerten is saying.

 

[MikePA]

Geez guys - - they are backwards. I plug the tester in & it tells me the common & hot are reversed. I shut off a breaker, pull the outlet & take a look. Sure enough the black is wired to the side that says 'white'. Pretty stupid, but consistant throughout the house. As i said, it is hard for me to do physically, but I'm plugging away at it.

I would still like to know the consequences of usuing the outlet with the common/hot wires switched. No one is cutting off ground prongs - - but I see what bigerten is saying.

I didn't understand the ground prong comment either since it's irrelevant to your question.

The tester confirmed it's wired correctly at the panel. As others mentioned, the only issue would be one of polarity. Since you have not had any problems, maybe it's not an issue. Perhaps an electrician could comment....about polarity.

 

[Egon]

Have all the other connections like lights been checked for polarity?

If the lights are backward you will have a hot wire at the light when the switch is in the off position.

 

[MikePA]

If the lights are backward you will have a hot wire at the light when the switch is in the off position.

Excellent point re: the wire that is switched. This is true everywhere there's a switch or a switched appliance, light, etc.

 

[MossRoad]

I didn't understand the ground prong comment either since it's irrelevant to your question.

I think it was a good point, Mike. Lots of folks remove the ground plug, especially if it is an older house with outlets that don't have the ground plug. They either clip off the ground or use one of those adapters that converts a three pronger to a two pronger.

If the plugs are wired in reverse polarity AND the ground is removed all it would take to ZAP the bajeebers out of you is if you touched the case of a cheap appliance and a metal window frame on an aluminum sided house. Weird stuff like that happens.

 

[KPark]

I would think the washing machine would be questionable with the metal case ground now being 'hot' and the water possibly making contact with real ground. Could be a shocker. I've felt the result when someone wires one appliance one way and the one right next to it the other (tingly).

I think there is more danger having a mixed polarity household than one that is completely backwards. The less time it takes to do the chore of rewiring, the safer you and your family will be. Maybe its time to call a favor from a friend or two or three to help you do it in one sweep. If you verify with a meter all the points that need to be redone, it will make it quicker to fix when you kill the power. Good luck with the re-do.

 

[JB4310]

Have all the other connections like lights been checked for polarity?

If the lights are backward you will have a hot wire at the light when the switch is in the off position.

??? Then the light would never go out, but that couldn't happen, first off a single pole switch doesn't have an "off" position, power comes in one side and out the other, one way would still turn off the light. That wouldn't matter at the switch. the problem as I did mention is especially with any light socket, if the switched hot goes to the outer threaded socket instead of the little tab at the base of the light socket, there's a much higher risk of electrical shock due to the fact that it's not to difficult to come in contact with that threaded base holder compared to the tab at the bottom of the socket.


Tdog, you wanted to know the consequences of running reversed polarity.
That's why I mentioned the plug in lamps, it's the same thing as the switched light, and what Biggerten said is relevant, in that at least if you had an independent ground even on a reversed polarity cord, it would provide some protection when using different power tools or appliances. wouldn't help with the light socket scenario.

How old is the house?

Don't forget not all white wires are neutral, wire coming from a certain switchs for one, both black and white will be hot when switch is closed.
I'm not an electrician, but have some basic wiring knowledge.

JB

 

[MossRoad]

Maybe its time to call a favor from a friend or two or three to help you do it in one sweep. If you verify with a meter all the points that need to be redone, it will make it quicker to fix when you kill the power. Good luck with the re-do.

A rewiring party! Drink beer AFTER it is done!

 

[jayste]

I'm still puzzled over wiring the whole house with 10ga wire! That makes my hands hurt just thinking of and typing it!

 

[Bird]

I'm not enough electrician to know for sure, personally, but in our RVing days, I read a number of stories about damage to RV air-conditioners, refrigerators, microwaves, etc. from two electrical problems in RV parks. One was low voltage and the other was reversed polarity. Simple and cheap plug-in testers are available for both. The only time I encountered low voltage was in Elkhart, IN, where the voltage dropped as low as 105 volts in the August heat, but no damage to anything. But I found reversed polarity at an RV park in Canon Beach, OR, and at one in Apache Junction, AZ. In those two cases, I reported the problem to the park management, they had no idea what I was talking about, so I showed them, and told them I'd be glad to fix it myself if they just showed me where to shut off the power to that outlet.

In Sayre, PA, the park claimed to have 30 amp service and had a 30 amp outlet, but would kick the breaker with a 20 amp draw. It seems the electrician who changed the 15 or 20 amp outlets to 30 amp outlets didn't change the breakers, so the next day he changed the breakers. I asked whether the wiring size was adequate and he assured me it was, so I had no more problems there.

 

[JB4310]

??? Then the light would never go out, but that couldn't happen, first off a single pole switch doesn't have an "off" position, power comes in one side and out the other, one way would still turn off the light.

My bad, a single pole switch does have an open/off position, but what I was trying to say is it would still turn off the light no mater if it was switching neutral, maybe that's what Egon was trying to say. Switching neutral should never be done also, it would leave one part of the socket hot all the time, even with light off.


Edit:
I was taking what he was saying as, the switches were wired backwards (even though he did say lights ) wouldn't mater at a switch that was strictly a load switch, in other words one wire bringing hot in and the other taking hot to the fixture. would of course mater if the switch box also carried the neutral and they were switching neutral.end edit:

JB.

 

[20 20]

I'm still puzzled over wiring the whole house with 10ga wire! That makes my hands hurt just thinking of and typing it!

I am also, 10ga is way over kill.

 

[Tdog]

How old is the house?

The house is about 1980 vintage. Someone mentioned a licensed electrician - - I doubt seriously that one had ever been in this house. The privious owner told me he built the house & I know he did a lot of the work himself. He even made a point of bragging about the 10 gage wire, but somehow failed to tell me about all the reversed outlets. I sure wish I could talk to him now to see why, but he was over 70 at the time of the sale so I don't think I'll be talking to him soon, short of a seance. AMEN on your 10 gage comments jayste & 20 20.
I've been in the house for over 16 years, so I'm a little derelict in correcting this problem. The outlets run whatever is plugged into them, so it didn't seem to be an issue. Now, I think it is an issue & I'm working on it.

 

[eepete]

A modern device doesn't care about which wire is hot or neutral. If it needs a safety ground, it's 3 prong. If it does not need a safety ground, like a lot of chargers and wall warts for power, then the device could care less and typically the power goes right into a switching supply for that device which isolates all remaining circuitry, including any an end user that could come in contact with any external part of the device. There was a very brief period, perhaps back in the 50's or 60's where some devices that were two prong had the different sized prongs and had to be wired correctly. So many houses had problems that this way of "doing things" was quickly abandoned.

All the comments on lights backward are correct. They work, but the desire to have the hot wire on "the button" is a safety concern.

One other problem with cutting off the ground pin on a device is that some devices use the ground for both filtering of the AC and as a place to dump voltage transients or spikes. If that ground lug was also connected to a metal frame on the device, there could be more of a hazard than if the metal frame was just floating. And of course the device, such as a surge suppressing plug strip, won't work as well.

As for the 10 gauge wire, maybe they had it left over and didn't want to toss it out? I ran 12 gauge wire to my outside receptacles on poles around the property, the runs were about 200' and then wired a 15 amp breaker. I have another outlet out 500 feet on 10 gauge and a 15 amp breaker. But inside a house, well, yeah. I can't believe they got the wire around the screws in the outlet. Hard to do, rough on hands. My house has 20 amp outlets and my hands hurt for weeks after connecting them all up. I understand why electricians charge much more if you want 20 amp outlets. It hurts!

As for what to do, you have no choice but to make it right. Devices plugged into your outlets and people working on the house's wiring assume it's done right. If someone plumbed your diesel tank into your hydraulic oil reservoir, you would not post asking if it would work OK, you'd fix it. So fix it.

MossRoad had it exactly right- a re-wiring party with beer afterwards. I hope he'll accept my friendly amendment and have some pizza there too!

Pete