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Posted By: bdonus ground size - 12/15/06 01:39 AM
need to know what size groung conductor to use for the main ground to the water pipe for a 1600 amp service with 4 sets of 600 mcm cables to the utility transformer.
Posted By: Luketrician Re: ground size - 12/15/06 02:24 AM
With the information given, table 250.122 shows 4/0 if the egc is copper, or 350 if it's al/cu. 250.122 (F) talks about conductors in parallel also. This should get you started.
Posted By: gfretwell Re: ground size - 12/15/06 03:58 AM
You use 250.66, not 250.122
I read it as the max required will be 3/0 copper or 250 MCM al.
Posted By: Luketrician Re: ground size - 12/15/06 04:23 AM
Thanks, and apologies for the mix-up, 250.122 is for grounding raceway's and equipment. Seen that first part, where it says minimum size egc, and the rest is history. [Linked Image]
Posted By: Yoopersup Re: ground size - 12/17/06 02:10 AM
If under the Chicago code its 18-27-250.66 page 93
copper (300) in a 1 1/4 inch conduit or tubing.
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