Additional eqiupment ground load side of ATS

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JLEECME

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I'm looking at a one-line diagram. The engineer shows the main cabinet outside the building with the first point of disconnecting means in "CTE" cabinet. He shows the neutral ground bond at this location and all the grounding electrode conductors connected to the buss. From here we feed through two 4pole automatic transfer switches to the first piece of gear on the load side of each transfer switch MSH and EHA. He shows additional set of grounding electrode connections to the buss in MSH, but the ground to neutral bond is not shown so thats all good. But, off the ground bus in this gear is a line noted "Equipment grounding conductor to ground bus in CTE sized per NEC 250.122. Do not bond neutral and ground busses in MSH or EHA". We already have ground conductors ran along with the feeders through the ATS to the equipment. What would be the reason for this additional noted ground, is it required by NEC?
 
MSH is the main 3000A Switchboard inside the building, EHA is a 225A branch panel. The entire building is backed up on generator, one transfer switch feeds MSH and one transfer switch feeds EHA.
 
JLEECME said:
I'm looking at a one-line diagram. The engineer shows the main cabinet outside the building with the first point of disconnecting means in "CTE" cabinet. He shows the neutral ground bond at this location and all the grounding electrode conductors connected to the buss. From here we feed through two 4pole automatic transfer switches to the first piece of gear on the load side of each transfer switch MSH and EHA. He shows additional set of grounding electrode connections to the buss in MSH, but the ground to neutral bond is not shown so thats all good. But, off the ground bus in this gear is a line noted "Equipment grounding conductor to ground bus in CTE sized per NEC 250.122. Do not bond neutral and ground busses in MSH or EHA". We already have ground conductors ran along with the feeders through the ATS to the equipment. What would be the reason for this additional noted ground, is it required by NEC?
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Because you have your main bonding jumper at the CT cabinet. You don't have to bond it again at the DS or at the panel.If you have a 4 pole transfer switch that means that you will have to bond you neutral at the generator too. ( Bonding jumper, grounding electrode ....)
 
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Sounds like the note was put there to insure that no more than one neutral to ground connection would be installed as it would cause objectionable current. Could this be an auxiliary grounding electrode as per 250.54?
 
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The engineer shows the main cabinet outside the building with the first point of disconnecting means in "CTE" cabinet.

With a 3000 amp + service, what "point of disconnecting" means is "in the CT cabinet" ?
 
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