turning 2-pole circuit into 1-pole by simply disconnecting on ungrounded conductor

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RustyShackleford

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Location
NC
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electrical engineer
Came across this ... Kitchen had originally been wired with 50amp/240vac circuit for an electric range. At some point it was replaced with a gas range (only requiring 120vac) and they simply replaced the 240v receptacle with a 120v one and capped off one of the hot conductors, but left the 6/2 wiring and 50amp double-pole breaker in place.

Is this legal ? It seems sketchy to me. The main problem being that the OCPD is several multiplies of the new range's MCA. Also, I need to check again, but I don't think it's 6/3 wire, so they're still using EGC as the neutral. I suppose if I simply replaced the 50amp double-pole breaker with a 20amp single-pole one, and then used that disconnected hot as a neutral (moving it to neutral bar in panel, of course), it'd be fine. Except for the wire being WAY heavier than the OCPD, which I suppose is fine.
 
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winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
If it is 6-3 wire, convert it back to a 50A range outlet, leave the 50A breaker, and use a plug in converter (with built in 15A fuse.)

If it is 6-2 wire, change to a single pole 20A breaker, use one of the hots as the 120V neutral, live with the miscolored neutral wire.

Jon
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I have done this many times. Re-wire and re-color one of the line conductors as a grounded conductor, change the breaker to a 1p 15a or 20a, and pigtail if necessary to fit the new breaker.

If the OP's example had a line conductor capped off, they must have used the bare conductor as both grounded and grounding, which was dumb with the extra conductor still available.
 

scrubbin

Member
Location
PA
Occupation
maintenance Tech
I think I'd do like Winnie said reconnect as it was originally wired and use a converter also as Winnie said. Then if you decide to back to electric just unplug the converter.
Converter:
 

RustyShackleford

Senior Member
Location
NC
Occupation
electrical engineer
I think I'd do like Winnie said reconnect as it was originally wired and use a converter also as Winnie said. Then if you decide to back to electric just unplug the converter.
Converter:
I believe this adapter is meant to plug into a 4-wire 240v receptacle, which I wouldn't have, if, as I suspect, it was originally wired without a neutral (apologies for posting without complete information), as ranges almost always were in the past.

I think the only good solution is to do as suggested above: put in a 5-15 or 5-20 receptacle, and a single-pole 15- or 20-amp breaker, and use one of the currently-ungrounded conductors as a neutral. I doubt I'd have to re-identify the neutral; presumably one of the wires in the 6-2 romex originally used was white; I might have to un-re-identify it :cool:
 

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
If the original install was 6-2 'Romex', then it was likely a code violation from the get-go. You were never permitted to use the bare ground of NM cable as the neutral for a circuit.

You were permitted to use the bare conductor of type 'SE' cable.

If they had 6-2 NM cable for a 120/240V load, then when you go to reuse it, investigate carefully, and assume that the original installer didn't have a clue.

-Jon
 

GoldDigger

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Location
Placerville, CA, USA
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Retired PV System Designer
I think I'd do like Winnie said reconnect as it was originally wired and use a converter also as Winnie said. Then if you decide to back to electric just unplug the converter.
Converter:
For those who are wondering how to reset the 15A overload protection when the unit is out of reach behind the stove, don't worry. It uses a non-replaceable fuse. :)
 

RustyShackleford

Senior Member
Location
NC
Occupation
electrical engineer
If the original install was 6-2 'Romex', then it was likely a code violation from the get-go. You were never permitted to use the bare ground of NM cable as the neutral for a circuit.

You were permitted to use the bare conductor of type 'SE' cable.

If they had 6-2 NM cable for a 120/240V load, then when you go to reuse it, investigate carefully, and assume that the original installer didn't have a clue.

-Jon
I misspoke. It probably was SE. I need to have another look. At any rate, even if it was acceptable back then, it's certainly not acceptable now, or to me in any case; I'll use one of the hots as a neutral and put in a 1-pole breaker and receptcle.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
I believe this adapter is meant to plug into a 4-wire 240v receptacle, which I wouldn't have, if, as I suspect, it was originally wired without a neutral (apologies for posting without complete information), as ranges almost always were in the past.
Technically speaking, they were wired without EGCs.
 

RustyShackleford

Senior Member
Location
NC
Occupation
electrical engineer
Technically speaking, they were wired without EGCs.
Because, if a single conductor is attempting to serve both roles - EGC and grounded conductor - if actually accomplishes the latter by allowing current to flow to complete the circuit with ungrounded conductor(s), but doesn't accomplish the former because there's current inappropriately flowing in it ?
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Because, if a single conductor is attempting to serve both roles - EGC and grounded conductor - if actually accomplishes the latter by allowing current to flow to complete the circuit with ungrounded conductor(s), but doesn't accomplish the former because there's current inappropriately flowing in it ?
It's actually the grounded conductor that used to be allowed to also be used for grounding purposes.

Note that, when this was allowed, the conductor had to be the bare of SE cable or an insulated wire.
 

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
Tradition!

Seriously: In 6-2 NM cable with a bare copper EGC, the EGC is _intended_ to be used as an EGC. In 6-2 SE the concentric bare wires are _intended_ to be used as neutral conductors. I don't know if there is an actual practical difference, but the rules permitted one bare conductor to be used as a neutral, but not the other.

-Jon
 
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