Bond Disconnect Enclosure to Ground Ring?

[monza2t]

Long time lurker, first time poster here.

So I have an AHJ requiring that we run a bonding jumper from an exterior mounted (on building wall) NEMA 3R disconnect switch enclosure to a building ground ring. This is a building with a a service that is bonded to all the applicable grounding electrodes available. The disconnect is being fed from a panel that is fed from the service entrance panel and there is no transformer in between the SE panel and this disconnect, so I don't have a separately derived system. Of course there is an ECG pulled with the phase conductors to the disconnect. The disconnect feeds an AHU outside on a pad.

To me this violates 250.121 in that I'm effectively extending the circuit's ECG to a grounding electrode, or if in other words installing a GEC thats bonded to an ECG.

Thoughts?

Thanks in advance, Paul

 

[Dennis Alwon]

The authority having jurisdiction is incorrect in requiring you to install a bonding jumper to the ground ring. You have a feeder or branch circuit to an ahu. Ask the authority having jurisdiction what section he is citing.

 

[infinity]

I agree with Dennis this is not required because the branch circuit must have the EGC run with it and the inspector is incorrect. There is no violation if you do connect it to the ground ring.