Proper neutral ground bond locations for apartment/multi-family complex?

[Electric-Light]

They usually have 208Y/120 for final distribution with three phase power made available to elevators and central chiller system. Larger complexes receive 480v and use 480v elevator and mechanicals, then use on-premise 208/120 transformers.

Depending on size of complex, electrical room maybe on each floor, or in one location with three phase power coming to electrical room.

The tenant panel receives two lines, neutral and a ground. Is the "main panel" within the tenants' unit considered subpanels?

Should there be neutral ground bond at each tenant's panel, at each electrical room and/or at the building service entrance?

 

[chris kennedy]

Service entrance as per 250.24(B) and any trannys as per 250.30(A)(1).

 

[Dennis Alwon]

From your description it sounds like there are other panels that feed the main panels in the tenants apartments. These would then be considered sub panels and the grounds and neutrals should be kept apart in the apartments.

 

[Electric-Light]

From your description it sounds like there are other panels that feed the main panels in the tenants apartments. These would then be considered sub panels and the grounds and neutrals should be kept apart in the apartments.

If the tenants are individually metered, would that be upstream of meter bank or downstream of each meter?

 

[iwire]

If the tenants are individually metered, would that be upstream of meter bank or downstream of each meter?

Could be either.

 

[LarryFine]

The tenant panel receives two lines, neutral and a ground. Is the "main panel" within the tenants' unit considered subpanels?

If the feeder has OCP at its source, and there's a separate EGC (you said there is), then it's a sub.

Should there be neutral ground bond at each tenant's panel, at each electrical room and/or at the building service entrance?

Not in the apartment, yes in the room (transformer secondary or it's panel), and not relevant ahead of the transformer.