National Electrical Installation Standards

Standards as High as Your Own

Tuesday, May 19, 2020


Good Day Code Friends, can I install 3 #6 and 1 #8 stranded cu. in a 1" conduit to feed a swimming pool?

Cameron Davis



Hello Cameron,

Thanks for the question. To provide an exact answer to this question, the conductor insulation type would need to be provided and the type of conduit the conductors are being installed in would need to be provided. The method to determine the conductor fill is not exceeded is found using Tables 5 and 4 in Chapter 9 of the NEC. Find the square in. area required for each of the conductors from Table 5 and add them together. Take that sum of the total square in. area to Table 4 based on the Type of conduit the conductors are being installed in. Using the example of  (3) 6 AWG THWN stranded conductors and (1) 8 AWG THWN stranded conductor, a 1-inch PVC conduit would be appear to be adequate. As a reminder, equipment grounding conductors with branch circuits supplying swimming pool equipment generally must be insulated. Verify the exact requirements in accordance with Parts I and II of Article 680.

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