# Dumb GC question????



## MTN REMODEL LLC (Sep 3, 2010)

Hey Gentlemen... 

If you've got "old romex" (or K/T) with/out ground, what's the easiest way to identify hot/neutral ...without a a big long ground wire back to a known ground. ,,, shy of licking my finger and standing in a puddle.

I ask because that is my daughters situation with an old 1950 build Cali home. I've been stretching a long jumper all the way back to closest ground I can locate (sometimes plumbing... sometimes out the window and right to the mains ground.

Thanks:whistling:whistling

Peter


----------



## Tinstaafl (Jan 6, 2008)

If there's no difference in the individual conductor sheathing, I'm not aware of any other way than what you describe.


----------



## 480sparky (Feb 1, 2009)

Use a long drop cord plugged into a known properly-grounded receptacle and use the ground in the other end as a reference. Use a meter between it and the unknown conductor.


----------



## MTN REMODEL LLC (Sep 3, 2010)

480 and Tin....

Thanks... just thought there was some trick I didn't know or hadn't hought of...

480... basically that's what I'm doing.... I virtually don't have any grounded circuits... basically it's a shorter run to the main then to the garage which has the only grounded recep running off a sub panel. Actually, sometimes I do run to the sub panel when it's shorter/more convenient.

Thank ya

Peter


----------



## TAHomeRepairs (Jun 18, 2012)

Safety disclaimer......do not try this at home... But hypothetically you might be able to"rig" something up with a light up three prong receptacle tester, an extra receptacle, and a couple of jumper wires. The lights on the tester should tell you which way is which. Just sayin there may be another way....


----------



## tjbnwi (Feb 24, 2009)

Try a voltage tick, if there is enough separation between the two conductors, you should be able to isolate the hot leg.

Tom


----------



## 480sparky (Feb 1, 2009)

tjbnwi said:


> Try a voltage tick, if there is enough separation between the two conductors, you should be able to isolate the hot leg.
> 
> Tom


Many times, the neutral is switched in old wiring. A Dummy Stick will light up on an ungrounded neutral.


----------



## iggy (Mar 3, 2013)

We used LED testers


----------



## MTN REMODEL LLC (Sep 3, 2010)

iggy said:


> We used LED testers


Everyone thank you...

But Iggy.... I guess I'm not sure what you mean by an LED tester. Is there a model# maker for one that identifies "hot/neutral or "polarity" for lack of better word" on AC.

I just use a multi-meter... don't really like/confident in a dummy stick except in some instances.... but maybe fluke has a more sophisticated LED (and more expensive I'm sure),

Thanks for your advice.

Peter


----------



## DemRem (Apr 21, 2012)

I have a greenlee voltage tester that has been really good...not over sensitive and it reliably picks up a hot wire. I've used it a lot and hardly ever gotten a bad reading (the few times I did it beeped on a wire that was not hot but it has never failed to beep on a wire that was hot)


----------



## TAHomeRepairs (Jun 18, 2012)

DemRem said:


> I have a greenlee voltage tester that has been really good...not over sensitive and it reliably picks up a hot wire. I've used it a lot and hardly ever gotten a bad reading (the few times I did it beeped on a wire that was not hot but it has never failed to beep on a wire that was hot)


Yup,I forgot about the ole beep tester.


----------



## Cole82 (Nov 22, 2008)

If you are talking about receptacles why not just use an outlet tester. Then you will know what side is what.


----------



## MTN REMODEL LLC (Sep 3, 2010)

Cole82 said:


> If you are talking about receptacles why not just use an outlet tester. Then you will know what side is what.


This question of the OP (me) concerns 2wire no/ground systems... but thanks...I've got plenty of them


----------



## Cole82 (Nov 22, 2008)

MTN REMODEL LLC said:


> This question of the OP (me) concerns 2wire no/ground systems... but thanks...I've got plenty of them


If you remove the ground prong and plug it in. They show you if the polarity is reversed .:thumbsup: Identifying hot side takes 2 seconds.

Cole


----------



## MTN REMODEL LLC (Sep 3, 2010)

DemRem said:


> I have a greenlee voltage tester that has been really good...not over sensitive and it reliably picks up a hot wire. I've used it a lot and hardly ever gotten a bad reading (the few times I did it beeped on a wire that was not hot but it has never failed to beep on a wire that was hot)


I/ve got a greenlee gt-11 (just went at looked at it). Iguess I'm just skeptical when it beeps sometimes on the neutral , or in close proximity, on both. Guess I just feel more sure if I have a good actual contact MM, but of course , it can't tell me which is hot.


----------



## MTN REMODEL LLC (Sep 3, 2010)

Cole82 said:


> If you remove the ground prong and plug it in. They show you if the polarity is reversed .:thumbsup: Identifying hot side takes 2 seconds.
> 
> Cole


Cole.... I really stand corrected if you're correct. I've got enough of them, ... I'll cut the ground plug and,,,I'll try it as soon as I get a chance. I'm so dumb I never thought they had any electronics/method other than testing across neutral and ground to identify reverse polarity.

If I'm not at a receptical... I guess I can just approprately jump to test.

Hope you're right my friend... sure will save alot of trouble at my daughters place.

Best... Peter:clap:


----------



## 480sparky (Feb 1, 2009)

Cole82 said:


> If you remove the ground prong and plug it in. They show you if the polarity is reversed .:thumbsup: Identifying hot side takes 2 seconds.
> 
> Cole


If there's no ground in the receptacle, removing the ground prong will make no difference.


----------



## MTN REMODEL LLC (Sep 3, 2010)

480sparky said:


> If there's no ground in the receptacle, removing the ground prong will make no difference.


Thanks 480... I think you saved me some useless testing...


Just curious if you ever tried with no ground, what will it show... no lights... correct polarity... no ground... or are all the makes a little different.

Maybe that's one way how hot/neutrals get reversed in two wire ungrounded systems?


----------



## Cole82 (Nov 22, 2008)

This is why 480 is my electrician.

Cole


----------



## MTN REMODEL LLC (Sep 3, 2010)

480sparky said:


> If there's no ground in the receptacle, removing the ground prong will make no difference.


480.... I think you were saying that that tester will not report correct polarity (ie reversed h/n) and removing the ground plug will "make no difference".???

(Stupid but...Obviously removing the ground plug makes some difference, otherwise you can't plug it into a two prong recep)

Thank you


----------



## 480sparky (Feb 1, 2009)

MTN REMODEL LLC said:


> 480.... I think you were saying that that tester will not report correct polarity (ie reversed h/n) and removing the ground plug will "make no difference".???
> 
> (Stupid but...Obviously removing the ground plug makes some difference, otherwise you can't plug it into a two prong recep)
> 
> Thank you


if the recept is not grounded, the tester doesn't have a ground to refer to, and will simply return an 'open ground'.


----------



## Tinstaafl (Jan 6, 2008)

Without the ground connection, there is no reference with which the tester can determine polarity. Neutral would be at zero volts _with reference to ground_.


----------



## MTN REMODEL LLC (Sep 3, 2010)

MTN REMODEL LLC said:


> Cole.... I really stand corrected if you're correct. I've got enough of them, ... I'll cut the ground plug and,,,I'll try it as soon as I get a chance. I'm so dumb I never thought they had any electronics/method other than testing across neutral and ground to identify reverse polarity.
> 
> If I'm not at a receptical... I guess I can just approprately jump to test.
> 
> ...


Tin and 480... JUST TO SIMPLYFY/clarrify the issue...In reference to Cole82 above advising a receptical tester with the ground plug removed in an ungrounded receptical will work in regard to identifying reverse polarity (H/N), I think you both (an me) are saying that it will not function to correctly identify polarity.


----------



## MTN REMODEL LLC (Sep 3, 2010)

Tinstaafl said:


> Without the ground connection, there is no reference with which the tester can determine polarity. Neutral would be at zero volts _with reference to ground_.


Tin... I don't want to belabor a simple question, but neutral should/will be at 0 volts to ground anyway...regardless of the issue

I agree 100% with your first statement "Without the ground connection, there is no reference with which the tester can determine polarity."... just did not understand the second part.

Peter


----------



## Tinstaafl (Jan 6, 2008)

Point is, the only way for a tester to identify hot and neutral is to see which wire is at ground potential and which wire is above ground potential. With no ground for reference, there's no way to measure that.


----------



## MTN REMODEL LLC (Sep 3, 2010)

Tinstaafl said:


> Point is, the only way for a tester to identify hot and neutral is to see which wire is at ground potential and which wire is above ground potential. With no ground for reference, there's no way to measure that.


Thank you sincerely. I am in 100% understanding/agreement... just a symantec confusion on my part.

Best.... Peter:thumbsup:


----------



## TAHomeRepairs (Jun 18, 2012)

480sparky said:


> if the recept is not grounded, the tester doesn't have a ground to refer to, and will simply return an 'open ground'.


But it will show polarity too, no ?


----------



## 480sparky (Feb 1, 2009)

TAHomeRepairs said:


> But it will show polarity too, no ?


How can it?


----------



## TAHomeRepairs (Jun 18, 2012)

480sparky said:


> How can it?


I'll have to play around in the morning, and see if it works. It seems it can register open ground and reversed polarity simultaneously. But i'm not certain.


----------



## CarpenterSFO (Dec 12, 2012)

TAHomeRepairs said:


> I'll have to play around in the morning, and see if it works. It seems it can register open ground and reversed polarity simultaneously. But i'm not certain.


All a simple 3-prong tester does is look for 2 prongs at the same voltage, and 1 prong different from them, and report only differences from that expectation.

It can't detect if neutral and ground are reversed, and it can't detect neutral and hot reversed without a ground. If neutral and hot are reversed without a ground, it will report the missing ground; then after that is fixed, will report the hot and neutral reversed.

All the while neutral and ground can be reversed, which is one reason that equipment grounds are supposed to be easily distinguished from other conductors.


----------



## TAHomeRepairs (Jun 18, 2012)

So yes you Sparkys are correct, duh, just had to see for myself. Does not show polarity without ground. Not worthy...









In my defense, I never claimed to know how or why the little lights light up, just that they do or don't.....


----------



## CarpenterSFO (Dec 12, 2012)

...


----------



## Tiger (Nov 21, 2007)

Since this is your daughter and you might care if she were electrocuted...there are two ways to make this system safe. One is to rewire with a wiring system that has a ground, the other is to replace every outlet with a GFCI outlet.


----------



## MTN REMODEL LLC (Sep 3, 2010)

Tiger said:


> Since this is your daughter and you might care if she were electrocuted...there are two ways to make this system safe. One is to rewire with a wiring system that has a ground, the other is to replace every outlet with a GFCI outlet.


Thanks Tiger.... I'm aware... matter of fact, this question arose looking for an easy way to determine (confirm) hot/neutral for GFI install. (Easier than stringing a ground jumper all the way back to a ground).

When we open it up for a remodel, it get's all new electric from an old FedPacific main to the last recep.

Peter


----------



## tenon0774 (Feb 7, 2013)

If you don't want to violate your new tool.

And will still give you an "ungrounded recept." code with the lights, but you already know that.

You're using it for a polarity check, no?


----------

