National Electrical Installation Standards

Standards as High as Your Own

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Monday, January 1, 2018

Question:

Pursuant to the current NEC, what size breaker and gauge wire are needed for a 50 foot run for a 14.5kw range being installed in a home?

Jeff Park

A

Answer:

Hey Jeff thanks for your questions. Note 4 to Table 220.55 allows Table 220.55 to be used for determining the load of a single household range. Note 1 to that table requires the values in Column C to be increased by 5 % for each kW or major fraction thereof for ranges above 12kW.

Your example of a 14.5 kW range would be 14.5 - 12 kW = 2.5 kW (rounded up to 3) results in 3 X 5% or 15 % is added to the column C value. 8 kW plus 1.2 kW (15% X 8kW) = 9.2 kW.

9.2 kW x 1000 = 9200 divided by 240 volts = 38.33 amperes. Based on termination ratings of 60 degrees C (110.14(C)) using Table 310.15(B)(16) the minimum conductor size is 8AWG copper or 6 AWG aluminum in the 60 degree columns.

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