Grounding electrode needed or not.

[james blake]

Hi guys. Today we were at a school running power to a mobile classroom that is to be fed from a outdoor, contractor installed Square D I-PAC (disco, X-former, panelboard, etc... all in one). While I was terminating the feeder to the mobile I noticed that there was no visible GEC leaving the gear to go to an electrode. We have installed several I-PACs and have always installed an GE/GEC for the transformer. This particular installation is not a service but the I-PAC is "suitable for use as service equipment". Would this install fall under 250.30 A 4 ex. 2 or did the AHJ and the contractor miss the GE/GEC installation? Thanks for any opinions.

 

[Smart $]

Is the transformer wired as an SDS? Typically, it is, and requires a GE per 250.30(A)(7).

The Exception you referred to does not apply.

 

[jim dungar]

This lable has to do with how the equipment is built not how it is wired/installed per the NEC.

'Suitable for use as service equipment', basically means that the connection between neutral and ground is made via a 'removable jumper' (i.e. a flexible strap, a removable bus link, or a screw). When the jumper is not installed the equipment may be used in any location.
A similar label is 'Suitable ONLY for use as service equipment, this means the neutral and ground are bonded together at the factory with a non-removable jumper. This equipment can only be used where a N-G is allowed by code.