CrapperEpiphanies
Member
- Location
- MD, USA
- Occupation
- EE
Per 250.30(C) Grounding Separately Derived AC Systems, Outdoor Source
"If the source of the separately derived system is located outside the building or structure supplied, a grounding electrode connection shall be made at the source location to one or more grounding electrodes in compliance with 250.50. In addition, the installation shall comply with 250.30(A) for grounded systems or with 250.30(B) for ungrounded systems."
I’m reading this passage as, a grounding electrode (ground rod, or some other approved electrode) is required at the source (generator).
What's tripping me up is the mention of compliance with 250.50 and 250.30(A)(4) information note 2, which I'm interpreting as bonding all electrodes together to form a GES.
250.30(A)(4) Grounding Separately Derived AC Systems, Grounding Electrode
Informational Note No 2: See 250.50 and 250.58 for requirements for bonding all electrodes together if located at the same building or structure.
My question is - if my SDS generator is located 20' away from an existing building - am I required to bond the generator's electrode to any electrode at the building with a bonding jumper sized per 250.66 OR does the EGC/SSBJ already establishes the bond between the generator grounding system and the building/structure it serves, and additional bonding jumper is not required?
If I do have to provide a bonding jumper how is it conveyed back to the building?
-In a separate conduit?
-Bare underground?
-Run within one of the raceways of the generator output feeder (seems like the EGC/SSBJ already present in that raceway would establish that bond with the building GES here)?
What if the generator was something like 300' away, does that change the answer to the above question?
Thanks.
"If the source of the separately derived system is located outside the building or structure supplied, a grounding electrode connection shall be made at the source location to one or more grounding electrodes in compliance with 250.50. In addition, the installation shall comply with 250.30(A) for grounded systems or with 250.30(B) for ungrounded systems."
I’m reading this passage as, a grounding electrode (ground rod, or some other approved electrode) is required at the source (generator).
What's tripping me up is the mention of compliance with 250.50 and 250.30(A)(4) information note 2, which I'm interpreting as bonding all electrodes together to form a GES.
250.30(A)(4) Grounding Separately Derived AC Systems, Grounding Electrode
Informational Note No 2: See 250.50 and 250.58 for requirements for bonding all electrodes together if located at the same building or structure.
My question is - if my SDS generator is located 20' away from an existing building - am I required to bond the generator's electrode to any electrode at the building with a bonding jumper sized per 250.66 OR does the EGC/SSBJ already establishes the bond between the generator grounding system and the building/structure it serves, and additional bonding jumper is not required?
If I do have to provide a bonding jumper how is it conveyed back to the building?
-In a separate conduit?
-Bare underground?
-Run within one of the raceways of the generator output feeder (seems like the EGC/SSBJ already present in that raceway would establish that bond with the building GES here)?
What if the generator was something like 300' away, does that change the answer to the above question?
Thanks.
