continuous load

[The electron man]

If I have a 37amp continuous load conductor
sized to * 1.25 = 46.25

so I would use #6 rated at 55amps

But what about my ocpd

Would I take my load of 37 * 1.25 = 46.25

There in no breaker rated at 46.25 so I would use a 50amp breaker correct ?

 

[infinity]

What is the wiring method (conduit and wire, MC cable, NM cable, Etc.)? In the list I mentioned all but NM cable can be used as a 75° C conductor meaning that #8 AWG is sufficient for 50 amps.

 

[The electron man]

What is the wiring method (conduit and wire, MC cable, NM cable, Etc.)? In the list I mentioned all but NM cable can be used as a 75° C conductor meaning that #8 AWG is sufficient for 50 amps.

Don't we use the 60° column for anything under 100amps and its conduit and wire

 

[HEYDOG]

If I have a 37amp continuous load conductor
sized to * 1.25 = 46.25

so I would use #6 rated at 55amps

But what about my ocpd

Would I take my load of 37 * 1.25 = 46.25

There in no breaker rated at 46.25 so I would use a 50amp breaker correct ?

Yes! For Nonmetallic Sheathed Cable with a 60 degree C rating!

 

[The electron man]

Yes! For Nonmetallic Sheathed Cable with a 60 degree C rating!

Its thhn so what column would I use and was the calculation for my ocpd correct ?

 

[infinity]

Don't we use the 60° column for anything under 100amps and its conduit and wire

Its thhn so what column would I use and was the calculation for my ocpd correct ?

THHN is 90° C conductor and can be used at its 75° C ampacity when the wiring method is conduit and wire. NM cable is limited to the 60° C ampacity due to 334.80.

 

[wwhitney]

Don't we use the 60° column for anything under 100amps and its conduit and wire

Yes as a default if terminal ratings are unlabeled. But in practice most equipment terminals are rated for 75C wire. So if you are using a 75C wiring method (not NM, not LFNC or LFMC in a wet location), and you confirm that the terminals are labeled for 75C wire, you get to the use the 75C column, even under 100A.

And yes, you need a 50A breaker with conductor ampacity of at least 46A.

Cheers, Wayne

 

[jim dungar]

Its thhn so what column would I use and was the calculation for my ocpd correct ?

Yes you match your protective device to your conductor's final ampacity.

 

[The electron man]

You guys rock thanks