Derating spliced conductors in the NEC

[patricknola]

I'm installing a hsb generator transfer switch where the home owner has a combo 12 circuit meter pan so I have to extend all the circuits in the combo meter panel to a new panel that I can connect a trasfer switch to. As I will be extending 12 circuits from old panel to new panel I wondering if I have to derate the conductors due to splicing and what part of the NEC covers this? TIA

 

[petersonra]

I'm installing a hsb generator transfer switch where the home owner has a combo 12 circuit meter pan so I have to extend all the circuits in the combo meter panel to a new panel that I can connect a trasfer switch to. As I will be extending 12 circuits from old panel to new panel I wondering if I have to derate the conductors due to splicing and what part of the NEC covers this? TIA

If the conduit between the old panel and the new panel is less than 24 inches long I don't believe any derating would be required. If the conduit exceeds 24 in long then you have to derate in accordance with the rules found in chapter 3 for more than three current carrying conductors in a conduit.

Splicing itself does not introduce any requirement to derate.

Just out of curiosity, how many wires are you planning to run between the old panel and the new panel.

 

[patricknola]

It

If the conduit between the old panel and the new panel is less than 24 inches long I don't believe any derating would be required. If the conduit exceeds 24 in long then you have to derate in accordance with the rules found in chapter 3 for more than three current carrying conductors in a conduit.

Splicing itself does not introduce any requirement to derate.

Just out of curiosity, how many wires are you planning to run between the old panel and the new panel.s

 

[patricknola]

It

It's going to be 28 conductors.

 

[infinity]

How long is your raceway? Splices do not require derating as Bob stated.