OCPD on secondary of MV transformer

[mshields]

I’m getting familiar with a facility that has primary metering. They own multiple pad mounted transformers and the secondaries feed the building as “feeders”. The secondary of one 2500kVA transformer in particular is what I’m wondering about. They’ve tapped it three times with three 2000A feeders each of which end in a 2000A switchboard with 2000A MCB. The sum of these secondary devices obviously exceeds 125% of the secondary (@480). Doesn’t there sum need not to exceed 125% of the secondary FLA? If the rule states that YES it does, is there an exception for industrial facilities under engineering supervision?

 

[mshields]

Hey - dumb ass - Go look at the table in Article 450.3 where you will find “non required” for supervised locations.

 

[mshields]

I should report this guy

 

[bwat]

You're probably in the clear because it only needs to be 250 or 300% plus round up, depending on cb or fuse, but it may be worth it to confirm that the primary protection required in table 450.3(A) that allow you to have no secondary protection is being achieved.

 

[Jraef]

Talking to yourself is not a sign of insanity. Answering yourself is...