The drawings I am working on show a #6 EGC run from the isolated ground bus of a 120/208V panel directly to the equipment grounding point of the supplying transformer. This is all fine and dandy with one exception. The transformer secondary consists of two conduit runs. There is only one isolated grounding conductor to run to the transformer. One pipe will have the 3/0 EGC and #6 isolated EGC. The other pipe will only have the second 3/0 EGC. The engineer does not see a problem. I think it’s a violation of 250.122(F). Am I wrong?
