Transformer Primary and Secondary Protection

[Rai136926]

I am designing to install 300KVA 3 phase 13.8kv-480/277, the secondary current is 360A, would i be ok to size the secondary with 400A? Or do i have to size it according to 450.3 (b)?

It is my understanding that 450.3(b) is the Maximum rating not a must follow. please advice.

 

[iwire]

I am designing to install 300KVA 3 phase 13.8kv-480/277, the secondary current is 360A, would i be ok to size the secondary with 400A? Or do i have to size it according to 450.3 (b)?

It is my understanding that 450.3(b) is the Maximum rating not a must follow. please advice.

You are correct those are just the maximum allowed, you can choose to go as small as you want.