I have some questions about remote structures and the requirements for service disconnects and grounding at each structure.
The main power is delivered to a panel with multiple main service disconnects located at the meter base, then the power is directed to three separate structures (barn,workshop, and main house).
There is no grounding rod at the main disconnect.(wrong)
The panels located in the garage and workshop do not have a main OCPD but have less than 6 breakers- is this acceptable for a service disconnect located at each remote structure? The panels for both structures have available slots to add more breakers which would exceed the rule of 6.
Also, should each subpanel should have it’s own GEC?
Lastly, the main house GEC appears to be (2) 12 gauge black insulated wires ran into the wall somewhere- I can not verify they are even going to an EGC-should this be called out?
BTW there are other electrical concerns not outlined here that will be called out.
The service disconnect requires a GES (grounding electrode system) and each separate structure requires a GES.
Each separate structure requires a GEC to connect to it’s own GES.
Each separate structure also requires a single disconnecting means or up to 6 individual circuit breakers.
The panel with the receptacle under it has what appears to be a GEC but the feeder has only 3 conductors so the EGC bus is not connected to anything but the electrode which is a hazard. There is a bunch of other things wrong here.
Unless this were installed prior to the adoption of the 2008 NEC each feeder is required to be 4-wire and have an EGC.
Regarding the two black conductors a 100 amp feeder would likely require #8 GEC’s.
If you look closely it looks like the tie bar between the left and right neutral buses has been removed meaning that the one on the left side is now just an EGC bus which must be bonded to the enclosure.
Are you sure about this? I carry these diagrams with me to remind me of the details. The three wire feed has a ground at the distribution/subpanel, but the four wire feed does not have a ground at the distribution/subpanel.
The 3-wire feed is showing a sub in a separate structure, as that was the only time a 3-wire feed was allowed. Because it is in a separate structure, it needs a GES.
The 4-wire feed I presume is assuming the sub is in the same structure as the main, therefore it does not need a GES. If the sub in the 4-wire feed diagram was in a separate structure, it too would need a GES.
Yes, my first response was made directly to the three sub-panels in this thread which are all in separate structures. In your two graphics the first one only ever applied to the sub-panel in a separate structure prior to the 2008 NEC. The second graphic depicts two panels within the same structure. If the sub-panel in the second graphic were in a separate structure then it would require a grounding electrode system.
