SBJ's SSBJ's, EGC etc

[mshields]

Actually, my question is about SSBJ's. Specifically, I'm looking at the grounding of an generator that will have associated with it, 2, 4 pole ATS's. So this is a separately derived system. As such the neutral will be bonded to ground at the generator. The generator will have a 450A MCB. Is the ground conductor from the center of the generators Y connection to this the enclosure housing the 450A breaker an Equipment Ground conductor (sized per one table) or is it an SSBJ (sized per the new table in the 250). Beyond this breaker, that's an EGC and therefore sized by 250.122.

Do I have that straight?

OR

Is it only an SSBJ if the neutral to ground bonding takes place at that first 450A main breaker?

Thanks,

Mike

 

[texie]

Actually, my question is about SSBJ's. Specifically, I'm looking at the grounding of an generator that will have associated with it, 2, 4 pole ATS's. So this is a separately derived system. As such the neutral will be bonded to ground at the generator. The generator will have a 450A MCB. Is the ground conductor from the center of the generators Y connection to this the enclosure housing the 450A breaker an Equipment Ground conductor (sized per one table) or is it an SSBJ (sized per the new table in the 250). Beyond this breaker, that's an EGC and therefore sized by 250.122.

Do I have that straight?

OR

Is it only an SSBJ if the neutral to ground bonding takes place at that first 450A main breaker?

Thanks,

Mike

I had this same question recently on a generator bonding jumper. My decision was to size the jumper using the assumed required conductors for 450 amps and Table 250.66 (2011) or Table 250.102(C)(1) (2014). The issue here is that this breaker is usually factory installed to the generator using wiring supplied with the generator.

 

[Smart $]

Actually, my question is about SSBJ's. Specifically, I'm looking at the grounding of an generator that will have associated with it, 2, 4 pole ATS's. So this is a separately derived system. As such the neutral will be bonded to ground at the generator. The generator will have a 450A MCB. Is the ground conductor from the center of the generators Y connection to this the enclosure housing the 450A breaker an Equipment Ground conductor (sized per one table) or is it an SSBJ (sized per the new table in the 250). Beyond this breaker, that's an EGC and therefore sized by 250.122.

Do I have that straight?

OR

Is it only an SSBJ if the neutral to ground bonding takes place at that first 450A main breaker?

Thanks,

Mike

Within the same enclosure, there is no such thing as a SSBJ. The first sentence of 250.30(A)(2) says, "If the source of a separately derived system and the first disconnecting means are located in separate enclosures, a supply-side bonding jumper shall be installed with the circuit conductors from the source enclosure to the first disconnecting means."

What you have there is the SBJ, and sized per 250.102(C)(1).

 

[mshields]

Excellent

Excellent

Thank you all