back feed through I-line panel

[caporter]

We are looking to back feed power, in case of loss of our generator, through a circuit breaker from a branch feed used to load bank test a generator. The breaker will be a Square D PGA36100SA rated to 1000 amps at 480 volts. All other power to the building will be down while repairs are made to a substation and this method has the automatic transfer switch downstream.

Is this ok or are there issues I need to be aware of?

 

[MikeHalloran]

The people making repairs to the substation would certainly be interested to know that downstream circuits will be hot.


Mike Halloran
Pembroke Pines, FL, USA

 

[caporter]

It will be separated from the substation work.

 

[caporter]

For those that are interested, Square D says we can reverse feed through the breaker wihtout issue.

 

[waross]

For liability issues, both financial and personal safety of the utility workers, you should involve your utility in your plans. The utility may want to Lock-off/Tag-off your service while this arrangement is in place. Although this may work from a technical point of view, the issues of best practice, possible lethal backfeeds, code violations, and terms of service are quite scary.

Bill
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"Why not the best?"
Jimmy Carter

 

[caporter]

Agreed, the autotransfer switch will be locked in the emergency position & the circuit breaker feeding it from the substation will be locked out as well.

 

[MikeHalloran]

AND, ethically and morally, you MUST also notify the utility.
They may wish to lock out and tag out your equipment, in addition to whatever you intend to do.
At least give them the opportunity to do so.


Mike Halloran
Pembroke Pines, FL, USA

 

[sibeen]

I don't know the circuit breaker and a cursory glance at the Square D website didn't track it down.

One thing to be careful of in a back-feed operation is the settings of the trip unit on the circuit breaker. A lot of the new 'intelligent' trip units from Schneider now come with functions such as "Reverse Power Flow" hidden down in the menu.

If you have one of these smart style trip units, make sure you read through the manual and disable any functions that may cause an issue.