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Wednesday, May 4, 2016

Question:

Can you splice different size conductors in same branch circuit, and fuse for the larger size. Thank you

Joe Millovitsch

A

Answer:

Hey Joe thanks for your question. If I understand it correctly, then no. In general conductors must be protected based on their ampacity as stated in 240.4. But there are some conditions such as in 240.4(A) through (G) that allow overcurrent protection to be larger than what would typically be required. So if one or more of those conditions applied it might seem that a smaller conductor did not have appropriate overcurrent protection when in fact it did. Connecting a larger conductor to the smaller one would then be acceptable.

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