# An electrifying mystery... (for amateur electricians, engineers, other people who shock themselves) **URL:** \ **Category:** Factual Questions\ **Created:** [October 8, 2012, 5:27pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105 "2012-10-08T17:27:21Z")\ **Posts on this page:** 10\ **Page:** 2
**Author:** ![trabajabamos](https://avatars.discourse-cdn.com/v4/letter/t/47e85d/32.png) [@trabajabamos](https://boards.straightdope.com/u/trabajabamos)\ **Post date:** [October 9, 2012, 3:35pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/21 "2012-10-09T15:35:31Z")
> [@engineer\_comp\_geek](#): > > Measure the voltage between hot and neutral in the outlets that were having a problem and compare it to the line to neutral voltage from each line measured at the breaker box. If the outlets are at a significantly higher or lower voltage then the neutral is likely floating. If the voltage looks correct, plug something that draws a lot of current into the outlet (like a hair dryer) and turn it on, then measure the voltage again. Thanks! Will do. ---
**Author:** ![trabajabamos](https://avatars.discourse-cdn.com/v4/letter/t/47e85d/32.png) [@trabajabamos](https://boards.straightdope.com/u/trabajabamos)\ **Post date:** [October 9, 2012, 3:36pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/22 "2012-10-09T15:36:38Z")
> [@jnglmassiv](#): > > Are you SURE the breaker hasn’t tripped? Sometimes the travel can be quite visually subtle. Fully exercise the suspect breaker. As indicated, I did this. But it’s a good thought. ---
**Author:** ![trabajabamos](https://avatars.discourse-cdn.com/v4/letter/t/47e85d/32.png) [@trabajabamos](https://boards.straightdope.com/u/trabajabamos)\ **Post date:** [October 9, 2012, 3:37pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/23 "2012-10-09T15:37:57Z")
> [@Snnipe\_70E](#): > > I underlined and bolded the clue to your problem. I doubt that you have a breaker problem, The outlet that you need to check out is the one the freezer was plugged into. If there is a loose wire and daisy chained through the outlet (a bad procedure) it probably heated up and then broke the conectioneverything went dead. Until you unplugged the freezer, the jar of unplugging the freezer caused the wires to rremake contact and a=every thingis now hot. This could be either the hot or the neutral. > > Unless you have a Zinsco panel breakers seldom go bad normally it is the wirring. > > To check for a neutral problem is easy. Check the voltage between the hot and neutral, between the hot and the ground, and the voltage between the neutral and ground. first two should be arround 120 VAC and the third neat zero. Good thinking. The freezer plug will certainly suffer my scrutiny. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [October 9, 2012, 4:26pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/24 "2012-10-09T16:26:03Z")
> [@engineer\_comp\_geek](#): > > Another possibility is a broken neutral. This would allow the circuit to mostly work as long as the loads between the two hots on that branch were reasonably balanced. This is a dangerous one because even though things seem to be mostly working, the neutral ends up “floating” between the two hots and as it floats down on one side (causing things not to work) it floats up on the other side, causing a dangerous overvoltage that can destroy things and cause a fire. > [@trabajabamos](#): > > So assuming that I have a multimeter and don’t mind digging around behind wall plates, is there something I could look for to confirm (or not) this possibility? > [@engineer\_comp\_geek](#): > > Measure the voltage between hot and neutral in the outlets that were having a problem and compare it to the line to neutral voltage from each line measured at the breaker box. If the outlets are at a significantly higher or lower voltage then the neutral is likely floating. If the voltage looks correct, plug something that draws a lot of current into the outlet (like a hair dryer) and turn it on, then measure the voltage again. measuring in the breaker box is the quickest, though it is the most hazardous method for people who might be inexperienced. you have to know about the inside of a breaker box and how to safely interact with it before doing that. an inexperienced person (not speaking specifically to the OP) can also get this information from measuring a number of receptacle voltages right at the front without taking the cover off. about half the electricity in your house comes from one of the two hot wires and the other half the other hot wire. you will then have some of your receptacles coming from each hot wire, not necessarily half. so if you measure a number of receptacles in various places around the you will eventually measure each hot wire. a good thing to have at the breaker box is having two receptacles there, one from each hot wire. if you use them for nothing but test points they are worth it. as **engineer\_comp\_geek** said the voltage between the hot and neutral, when you have a bad neutral connection will be significantly different. you will have a hot wire be maybe as low as 60V or as high as 180V, on branches affected by the bad neutral. on the circuit(s) with a bad neutral you could also see dim incandescent light bulbs and others very bight or burning out instantly. appliances would also not run or you might have them spark inside and smoke or die. a serious fire hazard. ---
**Author:** ![core\_dump](https://avatars.discourse-cdn.com/v4/letter/c/dec6dc/32.png) [@core\_dump](https://boards.straightdope.com/u/core_dump)\ **Post date:** [October 9, 2012, 7:11pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/25 "2012-10-09T19:11:30Z")
> [@johnpost](#): > > as **engineer\_comp\_geek** said the voltage between the hot and neutral, when you have a bad neutral connection will be significantly different. you will have a hot wire be maybe as low as 60V or as high as 180V, on branches affected by the bad neutral. This is absolutely ridiculous. (Not the factual information, just the fact that it was said). We have an OP whose circuit is likely opening due to heat expansion, and you guys are telling him to monkey around getting in his load center trying to find a weak neutral? Unf\*\* believable. The first few posts were the correct course of action. The wires in question could well be the neutral. Eliminate all backstabs, and screw down those loose receptacle screw-down connections. And yes, an open neutral is the most insidious thing you’ll even encounter. It will kill you. But a weak one didn’t cause this. Please be careful. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [October 9, 2012, 8:09pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/26 "2012-10-09T20:09:07Z")
> [@core\_dump](#): > > The wires in question could well be the neutral. > > … > > But a weak one didn’t cause this. :dubious: 😕 Why the hissy fit over a broken neutral being mentioned? ---
**Author:** ![core\_dump](https://avatars.discourse-cdn.com/v4/letter/c/dec6dc/32.png) [@core\_dump](https://boards.straightdope.com/u/core_dump)\ **Post date:** [October 9, 2012, 9:03pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/27 "2012-10-09T21:03:43Z")
> [@engineer\_comp\_geek](#): > > Why the hissy fit over a broken neutral being mentioned? I didn’t have a “hissy fit” over a “broken neutral” being mentioned. I had a hissy fit over solutions for a _weak_ neutral being given to a poor guy who’s just got a few backstabbed receptacles that aren’t secured. Next thing you know he’ll be moving breakers to different legs to even out your weak neutral. ---
**Author:** ![trabajabamos](https://avatars.discourse-cdn.com/v4/letter/t/47e85d/32.png) [@trabajabamos](https://boards.straightdope.com/u/trabajabamos)\ **Post date:** [October 9, 2012, 9:44pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/28 "2012-10-09T21:44:10Z")
> [@core\_dump](#): > > Next thing you know he’ll be moving breakers to different legs to even out your weak neutral. Not to worry; nobody has ever accused me of being overly credulous. This is the internet, after all, and you can be sure that I’ll filter all this advice a few times before I do anything rash. That said I appreciate everyone responding. Please don’t get embroiled in internet combat on my account. ---
**Author:** ![core\_dump](https://avatars.discourse-cdn.com/v4/letter/c/dec6dc/32.png) [@core\_dump](https://boards.straightdope.com/u/core_dump)\ **Post date:** [October 9, 2012, 10:21pm UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/29 "2012-10-09T22:21:42Z")
> [@trabajabamos](#): > > That said I appreciate everyone responding. Please don’t get embroiled in internet combat on my account. [Chris:] Hi, why don’t you have a seat in that chair right there [Homeowner:] Oh? wha? [Chris:] No, just have a seat, and keep your hands where I can see them, please. [Homeowner:] No man, I never like done this before, man! [Chris:] Do you know how many times I’ve heard that? [Chris:] Well, I’ve gotta tell you something: [Chris:] I’m Chris Hansen with Dateline NBC. [Chris:] And we’re doing a story on homeowners who don’t take care of their wiring. [Chris:] Now if there’s anything you want to say, we’ll be glad to hear it. [Chris:] Otherwise you’re free to walk out the door you came in. [Homeowner:] Am I gonna get arrested? [Chris:] That’s not up to me. Now I’m going to have to ask you to leave. ---
**Author:** ![Snnipe\_70E](https://avatars.discourse-cdn.com/v4/letter/s/b5a626/32.png) [@Snnipe\_70E](https://boards.straightdope.com/u/Snnipe_70E)\ **Post date:** [October 10, 2012, 3:28am UTC](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105/30 "2012-10-10T03:28:45Z")
> [@core\_dump](#): > > I didn’t have a “hissy fit” over a “broken neutral” being mentioned. I had a hissy fit over solutions for a _weak_ neutral being given to a poor guy who’s just got a few backstabbed receptacles that aren’t secured. > > Next thing you know he’ll be moving breakers to different legs to even out your weak neutral. I somewhat agree with core\_dump. I am amazed how many times when someone ask a question about a bad breaker, they get answers sending them to to the pannel to check for bad breakers or open neutrals. And a lot of the advice about open neutrals feeding the main panel. Ar trickey breakers or troubles in the breaker panel. An open neutral on a branch line will seldom cause a high voltage or a floating neutral. In a home there are few shared neutrals. To check for a bad neutral on a branch line outlet is the same as testing for a bad hot leg. Test it first at the outlet. test voltages between the hot, neutral, and ground. On here I see a lot of advice given to people who may or may not much about electricity. And some of the advice scares me. Where I somewhat dissagree with core\_dump is the complaint. Normally I do not voice where the advice is wrong, unless it is really dangerous. Example I cringe when I see advice to someone about puling a panel cover to someone who by their question may not know anything abut a electrical panel. Sorry now I will quietly sit aside (I hope). Just and old greasy snipe’s 2 cents. [Previous page](https://boards.straightdope.com/t/an-electrifying-mystery-for-amateur-electricians-engineers-other-people-who-shock-themselves/637105.md?page=1)