Open Neutral

pipe_bender said:
I am not doubting you but have always wondered where that code sections is? I want to cite it next time I run into those occupancy sensors that use the equipment ground to power the electronics.
I have actually seen a range converted to run on just '240' via a 6-50 welder plug, but all the elements were 240 the guy used a 50 watt control transformer to power the electronics so nothing ran on the equipment ground.
Click to expand...
250.140 Exception

Exception: For existing branch-circuit installations only where an
equipment grounding conductor is not present in the outlet or junction
box, the frames of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction boxes that are part
of the circuit for these appliances shall be permitted to be connected to
the grounded circuit conductor if all the following conditions are met.
(1) The supply circuit is 120/240-volt, single-phase, 3-wire; or
208Y/120-volt derived from a 3-phase, 4-wire, wye-connected
system.
(2) The grounded conductor is not smaller than 10 AWG copper or
8 AWG aluminum.
(3) The grounded conductor is insulated, or the grounded conductor
is uninsulated and part of a Type SE service-entrance cable and
the branch circuit originates at the service equipment.
(4) Grounding contacts of receptacles furnished as part of the equipment
are bonded to the equipment.
 
I wonder if the neutral current on the grounded conductor is higher or lower on a modern electronic range. The old ones were timer, light/lights, and those single receptacles that I never use. Maybe the oven lock solenoid on the self cleaning ones
 
Little Bill said:
It was never legal for the ground (EGC) to carry current on stoves and dryers. It was the neutral that was allowed to also be the EGC. The ground was never allowed to be the neutral. I've seen 10-2 with bare ground hooked up to dryers but that was never legal/permitted.
Click to expand...
My bad, good catch.
 
Little Bill said:
250.140 Exception

Exception: For existing branch-circuit installations only where an
equipment grounding conductor is not present in the outlet or junction
box, the frames of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction boxes that are part
of the circuit for these appliances shall be permitted to be connected to
the grounded circuit conductor if all the following conditions are met.
(1) The supply circuit is 120/240-volt, single-phase, 3-wire; or
208Y/120-volt derived from a 3-phase, 4-wire, wye-connected
system.
(2) The grounded conductor is not smaller than 10 AWG copper or
8 AWG aluminum.
(3) The grounded conductor is insulated, or the grounded conductor
is uninsulated and part of a Type SE service-entrance cable and
the branch circuit originates at the service equipment.
(4) Grounding contacts of receptacles furnished as part of the equipment
are bonded to the equipment.
Click to expand...
If you read carefully, that isn't what he is asking. I know there is a place that allows (or used to) occupancy sensors pilot lighted switches etc. to use the grounding conductor to carry that current, but not sure where it is and don't have the wherewithal to look.
 
Strathead said:
If you read carefully, that isn't what he is asking. I know there is a place that allows (or used to) occupancy sensors pilot lighted switches etc. to use the grounding conductor to carry that current, but not sure where it is and don't have the wherewithal to look.
Click to expand...
I don’t remember it being allowed by the NEC other than they were being used per the instructions. Labeled for such use. Individually in a single family dwelling it was probably not noticed. Make that a multi story apartment complex and suddenly we have considerable current flow on EG conductors.
 
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