overcurrent protection of 112.5 kva transformer

[electrical101]

I am presently on a new hospital job in Canada here is the problem.we are using a 400 amp /600 volt bus to feed a 112.5 kva transformer with 108 amp fla primary. 108 x 125 % = 135 amp. Now the hospital spec requires circuit breaker protection. canadian code allows us to go to the next size available breaker which is 150 amp.Now then if I install a 150 amp breaker on the primary does this affect the secondary. The local inspector tells me it does and allows the output fla to increase to over 400 amps which now requires a 600 amp transfer switch and distribution panel. The design has no secondary protection .any thoughts

 

[iwire]

Re: overcurrent protection of 112.5 kva transformer

I assume this is a Wye transformer?

I do not know the CEC but the NEC would have required OCP on the secondary side from the beginning to protect the transfer switch.

The primary protection of a Wye transformer can not protect the conductors and equipment on the secondary side.