Isolated Ground in Service Equipment

[curious101]

Good morning!
I have a small commercial building 120/208V, 3ph, 4w, 800A service. I have a few panels fed from the main distribution panel. One of the panels has isolated ground. When the isolated ground conductor is brought to the main service disconnect, is it terminated on the service ground bar or is there a separate isolated ground bar in the main service disconnect too and the two ground bars are connected with a bonding jumper?
Thank you!

 

[infinity]

The IG should land at the same spot that the MBJ is installed.

 

[LarryFine]

I'd say either is acceptable. The usual method is to attach it to the neutral bus where the electrodes terminate.

 

[curious101]

The IG should land at the same spot that the MBJ is installed.

Like shown below? Thank you!

 

[curious101]

I'd say either is acceptable. The usual method is to attach it to the neutral bus where the electrodes terminate.

Thank you!

 

[infinity]

Like shown below? Thank you!

I would land it directly to the neutral bus.

 

[LarryFine]

Like shown below? Thank you!

Again either is acceptable.

To take it to the extreme, the theory is to eliminate any deviation from zero volts, with the neutral being the reference.

 

[curious101]

I would land it directly to the neutral bus.

Thank you!

 

[curious101]

Again either is acceptable.

To take it to the extreme, the theory is to eliminate any deviation from zero volts, with the neutral being the reference.

Thank you!

 

[don_resqcapt19]

250.146(D) indicates that the isolated grounding conductor terminate at the equipment grounding conductor terminal of the applicable derived system or service. However at the service equipment or the location of the system bonding jumper for a SDS, equipment grounding conductors are permitted to connect to the neutral terminal bar.