Hi all,

I'll post some simple to read / understand images of IG methods.

As Don pointed out, it is a designing issue. If you simply bond the IG Receptacle to any convenient EGC or Grounded Enclosure / Box, that will satisfy the NEC Grounding Requirements [which could be as simple as a green jumper wire from the Receptacle's Ground Terminal to the 4s box it's mounted in!].

As to an effective IG, Isolation back to the subpanel is not too bad [sometimes [Linked Image]]. Running a dedicated IG conductor from the Grounding Electrode / Grounded Conductor Bond for the system feeding the IG circuit, to the panel[s] or subpanel[s] is usually the intended design method.
This can be sized to the highest OCPD for an IG branch circuit [normally #12 cu], but most of the time a #8 or #6 is specified.

Scott [electure],

Ya, the Binford 6100 IG system was a reference to Tool Time [Linked Image]

It would be the ultimate IG system of such mammoth complexity and overkill, Tim Taylor would totally be obcessed with it!

I won't be going to that extreme! [Linked Image]

I'll just post relavent examples.

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!