4 services in seperate enclosure

[styrfry]

I'm working on an existing 1600 amp indoor service with 3 disconnects in the gear, No main switch, and no room to add more services in the gear. I am adding a CT cabinet and 600 amp disconnect in a separate enclosure next to main service gear (through 6 inch long rigid nipple) and will tap off the bus to feed my 600.
Here's is where I am struggling.
1. Can I downsize my grounded service entrance tap conductor based on 250.24(D)1 / table 250.102(C)1
2. Can I run the GEC from my service into the main (3)service ground bus (where the grounding electrode conductor for that service is run to the water main)based off 250.64(D)1

 

[electrofelon]

I'm working on an existing 1600 amp indoor service with 3 disconnects in the gear, No main switch, and no room to add more services in the gear. I am adding a CT cabinet and 600 amp disconnect in a separate enclosure next to main service gear (through 6 inch long rigid nipple) and will tap off the bus to feed my 600.
Here's is where I am struggling.
1. Can I downsize my grounded service entrance tap conductor based on 250.24(D)1 / table 250.102(C)1
2. Can I run the GEC from my service into the main (3)service ground bus (where the grounding electrode conductor for that service is run to the water main)based off 250.64(D)1

1. Yes you can downsize the neuter if the load calc allows it.

2. If I am envisioning this correctly, I think you are all set with your gec for all service disconnects, based on the "common location" method in 250.64(D)(3).

Just a question, how will you be tapping to the bus exactly? Are there feed through lugs?

 

[styrfry]

I will be using lugs for all connections in main gear.