Meter Base

[Mike01]

Looking at a one line diagram that a contractor submitted for a small tenant build out it indicates a disconnect into the landlord?s troff and thru a meter into the space disconnect switch, my question is the meter he indicated is a 200A-480V-3ph meter base. My question is electrical meters require a neutral to operate correct?

 

[barbeer]

Not that I am aware of. Why do you assume there will be no neutral?

 

[Mike01]

no neutral

no neutral

the one-line only indicates 3 wires + ground from the landlord thru the meter into a disc then troff. spliced for the hvac unit and then to a 75kva xfmr. I just thought you had to have the neutral conductor for the meter to operate

 

[LarryFine]

the one-line only indicates 3 wires + ground from the landlord thru the meter into a disc then troff. spliced for the hvac unit and then to a 75kva xfmr. I just thought you had to have the neutral conductor for the meter to operate

Three points:

1) The space disconnect requires a grounded conductor, aka neutral, and this is where the service GEC's and premises EGC's all meet up.

2) Ahead of this point, the neutral and EGC are one and the same, so what you referred to as "+ ground" would be the grounded conductor.

3) As far as I know, most three-phase (and many single-phase) meters do have internal jumpers for a grounded conductor for the meter itself.

 

[iwire]

1) The space disconnect requires a grounded conductor, aka neutral, and this is where the service GEC's and premises EGC's all meet up.

I don't think we know if the 'space disconnect' is a service disconnect or a feeder....there may well be a main ahead of the trough.

3) As far as I know, most three-phase (and many single-phase) meters do have internal jumpers for a grounded conductor for the meter itself.

The only meter I am aware of that requires a connection to the grounded conductor is a meter that is metering single phase power (2 phases & Neut.) from a 3 phase 4 wire Wye supply system.