CI #4 Q.#67

[Stephen2awesome]

Question:

"Refer to 2014 edition of the NEC. What is the minimum required size for single-insulated, 60degreeC, TW copper conductors feeding a 460V 3-ph AC motor rated 150hp operating on continuous duty?

A. 4/0 AWG
B. 300 kcmil
C. 400 Kcmil
D. 500 Kcmil

"

I got B, 300 kcmil. Per NEC 430.250, FLC = 180A. Per NEC 430.22 for continuous duty, conductors must be 125%  of FLC. The book picked A. Please reply if you agree or disagree and why. Thanks.

 

[rg1]

Question:

"Refer to 2014 edition of the NEC. What is the minimum required size for single-insulated, 60degreeC, TW copper conductors feeding a 460V 3-ph AC motor rated 150hp operating on continuous duty?

A. 4/0 AWG
B. 300 kcmil
C. 400 Kcmil
D. 500 Kcmil

"

I got B, 300 kcmil. Per NEC 430.250, FLC = 180A. Per NEC 430.22 for continuous duty, conductors must be 125%  of FLC. The book picked A. Please reply if you agree or disagree and why. Thanks.

Something wrong. I got B. 300 kcmil and book also says same. Can you recheck it or share your answer book.

 

[Stephen2awesome]

Something wrong. I got B. 300 kcmil and book also says same. Can you recheck it or share your answer book.

See attached.

View attachment 10158

View attachment 10159

 

[rg1]

Lol. Old is Gold! Is there any change in 2014 NEC- no from your submission, then?

 

[rg1]

Have they missed to take 1.25 factor, is it, I have to verify?

 

[Stephen2awesome]

Have they missed to take 1.25 factor, is it, I have to verify?

I think they did miss the 1.25 factor. I was just making sure I wasn't missing something. Thanks. I believe this part of the NEC hasn't changed from 2011 to 2014. Thanks for checking.