winchester16
Member
I have a rtu with minimum ampacity of 139 and maximum of 150 amps. Can i use #1 thhn cu. conductors for this application?
If the RTU has 90 degree terminantons then yes, I don't believe it does so you would need at least 1/0 under the conditions of use stated in table 310.16. Also one should be familiar with 110.14. For the most part the 90 degree column is only for corrections and adjustments. There are few applications where 90 degree is the maximum tempeerature at the point of terminationI have a rtu with minimum ampacity of 139 and maximum of 150 amps. Can i use #1 thhn cu. conductors for this application?
If the RTU has 90 degree terminantons then yes, I don't believe it does so you would need at least 1/0 under the conditions of use stated in table 310.16. Also one should be familiar with 110.14. For the most part the 90 degree column is only for corrections and adjustments. There are few applications where 90 degree is the maximum tempeerature at the point of termination
I was reading 240.4b,123 and it says i could use the next higher standard overcurrent device rating above the conductors being protected, if the three conditions are met, which i think they are
Typically these nameplates will have a box for "minimum circuit ampacity". The conductor cannot be smaller than this number. It is not an OCPD value and there is no rounding up.I was reading 240.4b,123 and it says i could use the next higher standard overcurrent device rating above the conductors being protected, if the three conditions are met, which i think they are