Separate sources in the same conduit

[twinman]

In energizing an ATS whereas:

1) The normal feed is connected to the service (w/o standby emergency power) in which load is located (blbg #1).

2) The emergency feed is connected to the standby emergency generator utilized to back-up an adjacent building (bldg #2) which is served by a separate utility service:

The common of the ATS (load feeder) is to run in existing conduit occupied by other branch circuits from bldg #1. So, as long as there is service continuity, the commom of the ATS and the existing branch circuits are on the same service.

On emergency, the commom of the ATS is "live" from back-up generator in blg#2, but the branch circuits from bldg #1 are "dead".

Would this comply with 700.9 requiring "...wiring from an emergency source or emergency distribution overcurrent protection to emergency loads shall be kept entirely independent of all other wiring and equipment..."

 

[iwire]

I am opening this up again, it is not a duplicate.

My mistake, sorry to hold things up.

 

[RUWired]

In energizing an ATS whereas:

1) The normal feed is connected to the service (w/o standby emergency power) in which load is located (blbg #1).

So you have an ATS in building # 2 that has the normal feed and the load in building 1.

2) The emergency feed is connected to the standby emergency generator utilized to back-up an adjacent building (bldg #2) which is served by a separate utility service:

Question not related to emergency feeds is, does the ATS switch the neutral or not?

The common of the ATS (load feeder) is to run in existing conduit occupied by other branch circuits from bldg #1. So, as long as there is service continuity, the commom of the ATS and the existing branch circuits are on the same service.

On emergency, the commom of the ATS is "live" from back-up generator in blg#2, but the branch circuits from bldg #1 are "dead".

So the branch circuits in the same conduit as the load from the ATS are not classified as emergency circuits so that would be a violation of 700.9B.

Rick

 

[twinman]

I am tying into an existing emergency system, details of which are yet unknown. Is your concern of whether or not it will be a seperately derived system if the neutral is switched such as in a 4 pole ATS?

 

[RUWired]

I am tying into an existing emergency system, details of which are yet unknown. Is your concern of whether or not it will be a seperately derived system if the neutral is switched such as in a 4 pole ATS?

my concern was with the possiblity of parallel neutral currents when you tie two seperately served buildings together via the ATS equipment. I take it that there is more than one ATS in building # 2.

Rick