multi family dwelling grounding/bonding

[sparks27]

I'm working at a senior community. I have questions about the grounding of the panels for the individual units. The buildings are built in (1960) sylvania services. ok, 400a 1ph. 120/208 service. Six disconnects at meter section. Cold water ground and ground rod at service, bonded together. Then 100 amp sylvania 2 pole main breaker. 2- feeders plus nuetral( no ground wire), in 1-1/2 emt thru attic to apt.sub panel. The neutral goes to neutral bar. all wiring in apt. is steel flex. no ground wire. sound ok?

 

[infinity]

I'm working at a senior community. I have questions about the grounding of the panels for the individual units. The buildings are built in (1960) sylvania services. ok, 400a 1ph. 120/208 service. Six disconnects at meter section. Cold water ground and ground rod at service, bonded together. Then 100 amp sylvania 2 pole main breaker. 2- feeders plus nuetral( no ground wire), in 1-1/2 emt thru attic to apt.sub panel. The neutral goes to neutral bar. all wiring in apt. is steel flex. no ground wire. sound ok?

Sounds fine to me. The EMT is a listed EGC. The jacket of the cable (likely AC cable) is a listed EGC so no conductor type EGC's are required for either. The single phase, 120/208 seems strange for a service. What do you see as a problem?

 

[chris1971]

How long has AC Cable been listed as a EGC? Since the 60s?

 

[augie47]

We're fine until you got to the apartments. If it's steel flex it would need an equipment ground, if it's AC you are still good. Can you confirm the type wiring used on the apt branch circuits ?

 

[sparks27]

muti family dwelling

muti family dwelling

thanks for the responses, the apts. are fed with 1-1/2 emt with ss connectors. the branches are run in 1/2 --3/4 steel flex. depending on the cicuits oven, kitchen counter cirs. I guess my concern is these apts. are being upgraded with new panels 100a. sq.D qo models and branch cirs. being added and ground wires being run to the ground bar in the panel. and there is no real ground conductor. (conduit being the ground) these panels also are equipped with 100a main breakers. so is this to be treated as a sub panel? seperate ground and nuetral conductors? thanks for your responses.( long question)

 

[JohnJ0906]

thanks for the responses, the apts. are fed with 1-1/2 emt with ss connectors. the branches are run in 1/2 --3/4 steel flex. depending on the cicuits oven, kitchen counter cirs. I guess my concern is these apts. are being upgraded with new panels 100a. sq.D qo models and branch cirs. being added and ground wires being run to the ground bar in the panel. and there is no real ground conductor. (conduit being the ground) these panels also are equipped with 100a main breakers. so is this to be treated as a sub panel? seperate ground and nuetral conductors? thanks for your responses.( long question)

Yes. .......