Servicing an old three wire rage outlet.

[Angel Electric]

I responded to a call about a customer getting shocked by a wire within a three wire range outlet. I was told that the breaker was off and yet the incident occured. My experience told me that the breaker could be bad. It wasn't. I checked voltage at the breaker as it was off yet still nada and then i went to the outlet and pulled it out of the wall to begin checking its reading again nada. However I noticed that someone had by-passed the equipment grounding conducter and used the nuetral that had been pulled in with the four wire circuit. So I began to think about current return paths and felt that the current could posibbly been felt by the customer by the bleeding off of other return current coming into the customers service and feeding backwards along the nuetral of the range circuit. So what I did was explain to the customer that they needed an up to date four wire outlet to accomodate the new style range they were installing. I further explained that by someone having connected the nuetral coming from the panel that essentailly they were getting a current to device chassity and equipment chassity ground fault. I realize I should have done more testing but the customer bit on the quickest suggested sollution, about the outlet needing to be changed so no furtheer testing was achieved . So question is, what is it more right to have the equipment ground hooked up instead of the nuetral . Pick this to pieces b/c I really should know the answer confidently but do not.

 

[augie47]

Were they touching anything else at the time the stove was shocking them ?

 

[Dennis Alwon]

I So question is, what is it more right to have the equipment ground hooked up instead of the nuetral .

I don't think you will get a firm answer here as this was discussed before.

 

[ptonsparky]

Entirely legal install under previous codes. Check for loose connection at panel on range circuit. If good check, out what he was touching along with the range. That is probably where the problem is.

 

[Buck Parrish]

I responded to a call about a customer getting shocked by a wire within a three wire range outlet. I was told that the breaker was off and yet the incident occured. My experience told me that the breaker could be bad. It wasn't. I checked voltage at the breaker as it was off yet still nada and then i went to the outlet and pulled it out of the wall to begin checking its reading again nada. However I noticed that someone had by-passed the equipment grounding conducter and used the nuetral that had been pulled in with the four wire circuit. So I began to think about current return paths and felt that the current could posibbly been felt by the customer by the bleeding off of other return current coming into the customers service and feeding backwards along the nuetral of the range circuit. So what I did was explain to the customer that they needed an up to date four wire outlet to accomodate the new style range they were installing. I further explained that by someone having connected the nuetral coming from the panel that essentailly they were getting a current to device chassity and equipment chassity ground fault. I realize I should have done more testing but the customer bit on the quickest suggested sollution, about the outlet needing to be changed so no furtheer testing was achieved . So question is, what is it more right to have the equipment ground hooked up instead of the nuetral . Pick this to pieces b/c I really should know the answer confidently but do not.

The utilities neutral may be not making a good connection.
It is possible that the stove and the person touching may have been a better ground then the utilities. By chance is the house on a slab.

Of course thier are lots of scenarios.

 

[Angel Electric]

The homeowner claims that

The homeowner claims that

He claims he was touching the current carrying conductor? The residence is unit 416 of 840 Its a condo sky scraper community.

 

[Angel Electric]

He said he was taking the device apart

He said he was taking the device apart

When he was knocked back by one of the phase conductors. So is it better to use the equipment ground or the nuetral.

 

[kwired]

...So I began to think about current return paths and felt that the current could posibbly been felt by the customer by the bleeding off of other return current coming into the customers service and feeding backwards along the nuetral of the range circuit...

He would still have to be in contact with a grounded surface before being subject to any voltage potential As well as have a bad neutral connection someplace to raise the voltage to ground. If the neutral is good it will have a higher voltage difference to ground the more load it is carrying but should probably be less than 2 or 3 volts if all connections are good.

He claims he was touching the current carrying conductor? The residence is unit 416 of 840 Its a condo sky scraper community.

If touching a phase conductor he likely did not have it turned off or the breaker may have malfunction - or some other circuit is somehow inadvertently tied to this circuit - one leg of another circuit on this breaker and the other leg on another breaker is also possible.

When he was knocked back by one of the phase conductors. So is it better to use the equipment ground or the nuetral.

If using as neutral and equipment ground as permitted in 250.140 exception then you must use the neutral conductor.

There should not be much risk otherwise if all connections are good otherwise we would be required to disconnect the neutral with the ungrounded conductors.

You also may want to make sure you do not have an energized surface from some other source and the range outlet happened to be the grounded source in the shock incident.

 

[Angel Electric]

oooook

oooook

Code reference is good... And Ithink he screwed up and turned off the wrong breaker. The breaker for his range is oddly enough fed from an equipement panel where about twelve other ranges are fed from. Possible?

 

[Angel Electric]

one more question?

one more question?

Is the current from a two pole breaker feeding back into each others opposite phase 120 degress behind one another or is there another way to look at single phase double pole cicumstances? The nuetral serves what purpose?

 

[kwired]

Is the current from a two pole breaker feeding back into each others opposite phase 120 degress behind one another or is there another way to look at single phase double pole cicumstances? The nuetral serves what purpose?

The neutral is there to carry load from 120 volt devices (phase to neutral)that the range may have installed such as a light or time clock. If your range has no devices needing a neutral then you may not need a receptacle with a neutral terminal - This has been a topic of other threads.

 

[Denis]

zpped

zpped

due to failure to practice "test before touch"

let's see, I think this one is it

turns one off

ZAP, that's odd, I turned it off, didn't I

meanwhile in another kitchen

who turned off the stove

 

[LarryFine]

My first guess would be potential between the supply neutral and EGC systems.

Remember, the 3-wire supply contains a neutral, allowed to bond, not the opposite.

Is the current from a two pole breaker feeding back into each others opposite phase 120 degress behind one another or is there another way to look at single phase double pole cicumstances?

It's more likely tp be 120/208v 1ph in a building like this:

The residence is unit 416 of 840 Its a condo sky scraper community.

 

[boboelectric]

Then this is an an apartment with a subpanel,requiring a 4 wire feeder?

 

[ptonsparky]

When was this building built?

 

[Angel Electric]

old sky scraper equipement panels

old sky scraper equipement panels

The building was built in the seventies. These units dont even have panels for any of their circuits within the units all circuits run two variuos lighting and general purpose receptacles panels. Other units cirtcuitry is placed together with the circuitry from the unit Im working on...inside what i;d call a house panel.

 

[sparky59]

Sometimes people think they have been shocked and they really haven't. Sometimes when you're using your hands and arms a nerve will get compressed and give you a tingle. You can spend all day looking for that one.