Jason Paul
Member
- Location
- Raleigh
How do you know when we can to use the 90 degree column to size our wire in 310.15B16 other than by the type cable?
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- Thread starter Jason Paul
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- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
It is based on the insulation type however the 90 column may be used for derating but cannot be greater than either 60C or 75C depending on the terminals and the equipment.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Theoretically, if you could find terminations, devices, and equipment enclosures all rated for 90C you could use that column for basic sizing of the circuit as long as the wire type had a 90C column and it was not otherwise restricted (as NM is).
But it just does not happen.
If there were a really serious engineering issue that was solved by running wire at the 90C rating you could use a junction box at each end with 90C rated terminations and switch to larger wire to actually connect to your devices.
But it just does not happen.
If there were a really serious engineering issue that was solved by running wire at the 90C rating you could use a junction box at each end with 90C rated terminations and switch to larger wire to actually connect to your devices.
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