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Posted By: lite bulb grounding a ct cabinet - 06/22/16 02:31 AM
I have a 800 amp service can I put just one 3/0 in one of the conduits from the main panel to ground the ct cabinet
Posted By: ghost307 Re: grounding a ct cabinet - 06/22/16 02:59 AM
No.
A fully rated grounding conductor must be routed in each of the conduits for parallel conductors.
Posted By: lite bulb Re: grounding a ct cabinet - 06/22/16 03:19 AM
thanks thats a 3/0 in each conduit right?
Posted By: ghost307 Re: grounding a ct cabinet - 06/22/16 11:34 AM
Copper or Aluminum?
Posted By: HotLine1 Re: grounding a ct cabinet - 06/22/16 02:18 PM
Are you installing the GECs to the bond the neutrals in the CT? Or are you providing a bonding conductor for the CT cabinet?

Our POCO does not allow GECs in the CT cabinet, just bonding bushings IF required. Hot sequence the neutral block is bonded to the cabinet; cold sequence the neutral must 'float'. Then, bonding bushings may be required, dependent on the wiring method.

But, you are in Delaware, and Ghost is in Chicago, and I'm in NJ & referring to PSE&G rules.

Posted By: ghost307 Re: grounding a ct cabinet - 06/22/16 02:56 PM
If you're installing 2 sets of 500kcmil as Service conductors, you'll need to use NEC table 250-66 to size the ground conductor in each conduit.
Posted By: lite bulb Re: grounding a ct cabinet - 06/23/16 03:27 AM
Main service is comming into the ct cabinet in pvc, leaving the cabinet to a metal trough also pvc, out of the trough to the 800 amp main panel also pvc. I'll have to check on grounding the ct cabinet with the power company but I still need to ground the trough bonding will be done in main panel. Wire is 500 copper.
Posted By: lite bulb Re: grounding a ct cabinet - 06/24/16 01:57 AM
Power company does want a ground to the ct cabinet from main panel do I need a 3/0 in each conduit to the ct cabinet from the main panel or can I just put one 3/0 in one conduit also grounding the trough?
Posted By: HotLine1 Re: grounding a ct cabinet - 06/24/16 08:51 PM
The POCO wants a "ground" in your CT cabinet; do they want the enclosure 'bonded' or the neutrals and GECs bonded at the CT enclosure?

IMHO, the POCO is looking to have the CT 'bonded'.

Posted By: lite bulb Re: grounding a ct cabinet - 06/25/16 06:38 AM
The enclocure bonded
Posted By: HotLine1 Re: grounding a ct cabinet - 06/25/16 03:40 PM
OK, here the enclosure bond is made via the neutral lug(s) that are mechanically connected to the enclosure in a 'hot sequence' install.

In a 'cold sequence' install (disco or MOCP ahead of the CTs) the neutral 'floats' and a bond for the CT cabinet is required.

See 250.122
Posted By: Yoopersup Re: grounding a ct cabinet - 06/26/16 06:44 PM
from the ct cabinet to the ist main the Neutral is your bond,
also install a bonding strap or jumper from XO in CT cabinet to cabinet. (Usually supplied by manufacturer of Cabinet.
If not size a conductor using 250.66

Installing EGC would give you a parallel neutral as your also required to bond in MDP.

See Soares grounding book or goggle Soares info on net

http://iaeimagazine.org/magazine/1998/11/01/service-main-bonding-jumpers/
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