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Conduit Fill Calculator

Check raceway fill percent against NEC Chapter 9 limits.

Inputs

Inputs and assumptions

From NEC Chapter 9 Table 5. 12 AWG THHN is about 0.0045 sq in.

From NEC Chapter 9 Table 4. 3/4 in EMT is 0.533 sq in.

Wires of the same size.

Result

Allowed fill
40.0 %
Raceway fill
2.5 %
Screening tool. Verify against the NEC as adopted locally, the AHJ, nameplate data, and metered conditions before acting.

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Workspace

Keep the assumptions with the result.

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