Local Disconnect Switch for 13.8kV -208Y/120V transformer required?

[metta0810]

I'm working on a project where we need to install a 13.8kV-208Y/120V Transformer to feed non-rotating distribution loads. The Transformer is being fed from a remote source (located about 300 ft away) which has a breaker.

Do I need to provide a local disconnect switch on the primary side of the transformer? Does anyone know for what application that needs local disconnect switch in accordance with NEC?

Thanks

 

[dpc]

Per the 2011 NEC, a disconnecting means is required. If it remote, as in your example, the disconnect must be lockable in the OPEN position. See 450.14.

Interestingly, prior to this Code edition, transformers were not required to have a disconnect at all.

So if you can lock open the breaker, you should be OK. The location of the disconnect must be field marked at the transformer.