What are the effects of hot/neutral reversed wiring?

Discussion in 'General Electronics Chat' started by moeburn, Sep 1, 2013.

  1. moeburn

    Thread Starter Member

    Aug 16, 2013
    I'm living in a room where half the outlets are hot/neutral reversed, according to my little yellow outlet tester. I know of one effect of this: every time I change a lightbulb in the recessed lighting fixtures, I have to make sure the switch is turned off, so I don't get an electrical shock from touching the outer metal casing of the recessed fixture.

    But I also have a bunch of other weird electrical problems, and I was wondering if they will also likely be the result of the hot/neutral reverse. One is that every time I turn my computer on or off, my speakers make a loud pop-click-pop. The speakers are large, powered from a separate amp. It only happens when the amp is actually plugged into the computer though, so it's probably a crappy sound card.

    The other, is that I have a desk fan, a self-powered usb hub, and my computer, all plugged into a nice Kensington EMI filtering power bar. And every time I turn off or change the speed of the fan, I hear a 'ding' and my USB devices disconnect from the computer for about 2 seconds before reconnecting. I would have thought EMI filtering would fix that! I also tried a non-filtering power bar, just to be sure, but same issue.

    So other than getting electrocuted by touching metal casings, what are some other definite symptoms of having hot/neutral reversed? Just curious, I'm going to fix it anyway.
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
    Metal casings are not connected to neutral, they are connected to earth ground (third wire if you have them).

    Why not turn off the power, pull the outlets and swap the black and white wires?
    #12 likes this.
  3. MaxHeadRoom


    Jul 18, 2013
    The Neutral of your service is connected to Earth ground at the service panel.
    This should be the only point the ground comes in contact with the neutral.
    The vast majority of items or appliances it is of no consequence, but it usually means that any single pole switch will be in the neutral line so there will be a live or 'hot' that will go 'unswitched'.
    Incidentally your PC +5/+12v power supply common is also connected to earth ground
    jimmy001 likes this.
  4. WBahn


    Mar 31, 2012
    Since you know the problem exists, you should go ahead and correct it. For the most part it will only cost you some time and you don't have to do it all at once. It also affords a good opportunity for you to map out all the electrical outlets and fixtures in your house and mark which breakers they are serviced by. If and when you sell your home the inspection objections will probably require you to fix the problem and will put a bad taste in the buyer's mouth -- after all, if the house wiring is that messed up, what else was poorly done. Having it all correct and having a map of the house electrical plan does the opposite and puts a pleasant flavor in the buyer's mount -- after all, if the house wiring is all in order and even nicely documented, how many other things are equally well attended to?