Quote Originally Posted by Mgraw View Post
You could run a 25 amp circuit to a disconnect and then fuse the disconnect at 15 amps. If this is a commercial job, at least the engineers I deal with, always spec a fused disconnect at the unit.
Sounds like what one may expect in many cases. 25 amp supply covers worst case scenario, select fuse for actual equipment.

Quote Originally Posted by jap View Post

If this is a bid job and the engineer actually indicated the disconnect to be a "Non Fused" 20a disconnect, then a change order should be submitted to change the "Non Fused" disconnect to a 30 amp "Fused Disconnect" with 15 amp fuses and be done with it.

I think many will just put in 15 amp breaker and be done with it, they do have to pass electrical inspection.