Circuit Breaker Required on ATS

[mgardner]

Is a OCPD or disconnecting means required on the load side of a transfer switch?

I've always included a main breaker in the panel on the load side of a transfer switch. On this particular project, the contractor wants to take out the main breakers in the panels (part of VE). I can't find if there is a requirement for a breaker on the load side of the ATS anywhere. Is this just a habit I've picked up along the way or is it an NEC requirement?

Thanks!

 

[charlie b]

I can't find if there is a requirement for a breaker on the load side of the ATS anywhere.

There isn't one. The panel downstream, and the feeder from the ATS to that panel, can both be protected by the breaker upstream of the ATS.

 

[augie47]

I agree with charile, but if I might add, the panelboard must be rated no less than the overcurrent device that does protect it.

 

[dbuckley]

We did this one just a week or two ago in a slightly different context, might be of interest though: Thread: Transfer switch downstream fault

 

[charlie b]

And to that I will add, for I sometimes see this, that if the normal side feeder and alternate side feeders are different, the panel downstream must be rated at least as high as the higher of the two.