Emergency generator connection

[augie47]

I have been asked about an installation at a military installation (NG) that is still under review but it appears that there is a wiring arrangement for a emergency generator hookup comprised of 4/0 conductors connected to a back-fed 400 amp breaker (2 per phase) and routed to a point to be connected to a portable emergency generator. The job gets more interesting in that the provisions for the generator hook up consists of 200 amp camlok connectors )one connector per 4/0 conductor)
I have no idea what type protection the generator provides.
Anyone encountered such an arrangement ? (may be SOP for these facilities)

 

[ron]

I see similar at telephone company facilities.

Be sure they have a permanently install breaker interlock to function as a "manual transfer switch".

If it is a 4W application, the generator should not have a N-G bond, because they will likely not install a 4pole breaker.

 

[ActionDave]

....The job gets more interesting in that the provisions for the generator hook up consists of 200 amp camlok connectors )one connector per 4/0 conductor)
I have no idea what type protection the generator provides.
Anyone encountered such an arrangement ? (may be SOP for these facilities)

Common for cell sites that use portable generators around here.

 

[iwire]

Common for cell sites that use portable generators around here.

Don't they use a Kirk key system to prevent backfeed though?

 

[ActionDave]

Don't they use a Kirk key system to prevent backfeed though?

Not here, just a manual transfer switch, a lot of times a breaker interlock. The big problem was making sure that the cord and plug style connector matched all the different sites since there has been such a turnover in cell providers since the '90s from independents to the big dogs like ATT and Verizon.

 

[iwire]

Not here, just a manual transfer switch, a lot of times a breaker interlock.

So yes more or less, there is a mechanical means to prevent a backfeed.

Gus has not mentioned one.

 

[ActionDave]

So yes more or less, there is a mechanical means to prevent a backfeed.

Gus has not mentioned one.

Ahh, I see what you are saying. I took it for granted there was something to isolate the generator power.

 

[augie47]

Further input revealed the install was actually intended to supply power for temporary hook-up external to the building. After discussion the decision was made to connect the 4/0s together at the cam locks with a polaris type connector thus making it a parallel run.