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#83635 - 02/10/03 04:55 PM Underground Duct Bank
Al Kacoroski Offline
Junior Member

Registered: 02/10/03
Posts: 1
Loc: Richland WA 99352
Is there any guidance for size, placement, and configuration of underground duct banks carrying multiple conduits of varying sizes, with multiple conductors in each conduit. Current is 120 V control, so heat dissipation should not be an issue. Table B.310.2 has typical configurations for one conductor per conduit, all same size, but nothing for a mixed case.

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#83636 - 02/10/03 08:22 PM Re: Underground Duct Bank
nesparky Offline

Registered: 06/21/01
Posts: 650
Loc: omaha,ne
Just use the same rules for conduit size as you would for any other conduit run. All a duct bank is is a croup of conduits in the earth. WIre ampacity can be found in tables B.310.10 and B.310.11


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