Service Lateral ground question

Question is: “Does a main shut off located adjacent to meter outside require a separate grounding electrode in addition to the service lateral metal conduit buried at unknown depth and length?” There was no ground clamp on the conduit either…



Is the metallic underground conduit on the load side of the service disconnect?

Service entry cable going to sub panels is also in metal conduit. Still no ground strap or connection lug to conduit. I had thought a separate grounding electrode was required in case conduit became disconnected and it’s usually not deep enough?

Brett, I’ve read through your posts several times but I’m still not getting the installation. Can you lay it out in a linear fashion starting at the meter?

Sure, a picture’s worth a thousand words so I attached a few more. Layout is typical service lateral coming into meter base then feeding down to main breaker. Two grounds were connected here and leading through separate conduit from the conductors and presumably underground to connect to the sub-panels in the basement. I didn’t note any ground strap to conduit or any separate grounding electrode though it could be ground ring or something or would a long underground ground run to the sub-panels be adequate?

I’ve also attached a diagram of how it’s supposed to be but there’s some uncertainty here. In other words I couldn’t find a ground rod near the meter area…






So the conductors exiting the bottom of the service disconnect go into a metal raceway and then enter the ground continuing on to somewhere else within the same structure? If so the metal conduit would need to be continuous to the subpanel or the raceway would require a wire type EGC.

The two bare conductors are likely GEC’s going off to connect to two ground rods or some other electrode(s). They cannot be landed under the same lug unless it’s listed for the connection of two conductors (which it isn’t).

Also the neutral must be bonded to the CB enclosure, it may be factory bonded if the enclosure is listed as suitable for use as only service equipment otherwise there should be a screw or strap connecting the neutral to the enclosure.

OK, got it thanks. Looks to me like the defect is double tapping that ground lug.