Reversed Polarity


Old 07-28-07, 01:02 PM
monkeyboy's Avatar
Thread Starter
Join Date: Jul 2007
Posts: 2
Reversed Polarity

During a home inspection, I was informed that many of our outlets were "reversed polarity". Is this serious and how do I correct it?
Sponsored Links
Old 07-28-07, 01:51 PM
Pendragon's Avatar
Join Date: Jul 2002
Location: USA
Posts: 1,835
He probably means that the polarized plug side (the wide blade) is on the hot side (black) instead of the neutral (white) where it is suppose to be. It's an easy (if not time consuming) fix.

You would need to take out each outlet (with the power off of course) and flip the black and white wires. If one outlet is feeding others, you may only have to change that one outlet. An easy visual check is that the white wire goes under the silver screw, the black wire under the gold screw. Or, looking at the face of the outlet with the ground pin facing down (standard residential method), the white would be on the left, black on the right.
Old 07-28-07, 02:20 PM
ddr is offline
Join Date: May 2006
Location: New York City
Posts: 133
Pendragon beat me to it, but since I typed it out already:

It is important to keep polarity correct with certain devices, which is why many have "polarized" plugs, where one blade is wider than the other and can only fit in the receptacle one way. If the polarity of the receptacle is reversed, it defeats the purpose.

On a polarized receptacle, one slot is larger than the other to accept the wider blade of the polarized plug. This wider slot is the "neutral" side of the receptacle, with the smaller slot being the "hot" side.

The receptacle has screws to attach the circuit wires to: the hot wires are black (or sometimes red) and attach to the brass colored screws (which power the smaller slot) while the neutral wires are white and attach to the silver screws (which connect to the wider slot). If the white wire feeds the hot side and the black feeds the neutral side, you end up with reversed polarity, also known as a hot/neutral reverse.

The easiest way to check is with a plug-in three light tester which, depending on the combination of lights, will tell you if the receptacle is wired correctly and, if not, tell you the problem.

If the tester indicates a hot/neutral reverse, turn the power off to that receptacle (always double check that the power is off by testing it), remove the receptacle and check the wires. If you see that the wires are reversed, switch them to the correct terminals. If the wires go where they are supposed to, then the problem could be "upstream" that is, coming from the receptacle before that one in the chain. When this happens, the receptacle before may have the outgoing wires reversed, which will affect correctly wired receptacles downstream.

This may be your case. You said "a number" of your outlets had reversed polarity; if they are all on the same circuit, it is possible by fixing one that you will correct all of them. It may take some work to find the culprit. Once you feel you have fixed the problem, recheck all the outlets to make sure they have proper polarity.
Old 07-28-07, 04:18 PM
monkeyboy's Avatar
Thread Starter
Join Date: Jul 2007
Posts: 2

Thanks guys, I feel much better and less apprehensive to correct this.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes