Confused ???

[celtic]

Currently, we are in the process of wiring a 90+ condo building. The service(120/240V @ 2000A) that will supply this building is taken from a larger piece of EXISTING equipment downstream(4000A). The main panel serviced by this 2000A consitits of 2 switches (1600A and 1200A) that feed the meter banks. Each meter in the stack(4 per stack) in the banks contains their own disconnect (a meter main stack ).

I am confused by this picture of Mike's:

The design of our layout is similar to the picture, in that we have:
- a seperate ground to building steel
- parrallel feeders in conduit (4 wire, no EGC)
- a bus connection(s) instead of a through

The risers to the individual units consists of 2 ungrounded conductors, 1 grounded conductor and 1 EGC.

Am I to understand that EACH of the 90+ meters MUST have a neutral to case connection?

I can gather images of our installation if need be.

 

[pierre]

Re: Confused ???

If you are actually coming off of the load side of the 4000 amp switch (service), then your 2000 amp switch is a feeder and the grounding conductor and the neutral are to be separated.

If the switches are in the same building, you will not need to have any grounding electrodes, it would be treated the same as a 60 amp subpanel.

 

[celtic]

Re: Confused ???

We are coming off a 2000A fused switch(un metered - I believe) in the 4000 A gear.

The building we are working on is actually an extension (800 ft) of the existing building (800 ft).

 

[iwire]

Re: Confused ???

What you are adding are not services, they are feeders.

The service ends at the original service disconnect.

 

[celtic]

Re: Confused ???

Seems obvious NOW (subs vs. services)

Thanks guys.