I have a 60 HP fire pump I'm still playing with. FLC 169 amps at 208V. CT cabinet (no disconnect) will be 400-amp 3-phase. I noticed the AIC rating of the CT is 10,000 amp. The utility transformer is 500KVA.

My very rough estimate is 1388-amps for a possible AFC of 13,880 (I know this is rough). When bringing this up to my supplier, he tells me the only way to get AIC of higher I have to put a disconnect in it. Well that puts me up to a 1200-amp disconnect. (fire pump rules- NEC '99 695-4 for you savy types)

This seems odd that with disconnect it would be rated at 100,000 but without only 10,000. Any input or suggestions??