Article 240.21C transformer over-current protection

[Dan Kissel]

We have a 30+ year old facility that has several 75 KVA 480 D to 208Y transformers that meet all code requirements except that the 208Y side does not have an OCPD local to the transformer. Each transformers (T-L2 and T-L5) feed a single distribution panel with a main breaker, but the panel is over 100+ feet away. Do I need local OCPD devices within 25 feet of each transformer? Did the code change in this respect in the past 30 years?

 

[augie47]

Take a look at 240.92 for Supervised Industrial Installations and see if your installation qualifies.

 

[jim dungar]

Yes, the code has changed over the years. Back in the late 70's early 80's it was quite common to find installations such as yours, sometimes the secondary side panelboards were main lugs only.

 

[Danielt]

Per the IEBC, you do not have to comply with newer codes. If everything has been well maintained, and everything is working correctly, I would let it be.
You can always get an inspector to come out and look it over.