Cable sizing

Status
Not open for further replies.
M

mohsen1969

Member
My question is about the equipment maximum operating temperature limit factor for cable sizing.

According to NEC only on tables 310-16, to 310-19 for cable voltage range of 0 through 2000 volts there are 60 and 75 0C temperature rating. If I want to take into account the operating temperature of equipment for a MV cable (more than 2000 V) what should I do since tables 310-67 to 310-86 have ampacity just under 90 0C?

Mohsen Bakhshi,

Edmonton, AB
 
Re: Cable sizing

Tables 310.67 through 310.86 show ampacities for MV-90 (90 degrees C) and MV-105(105 degrees C) rated cables. Does the cable you are trying to look up have a different MV rating than these?
 
Re: Cable sizing

I have 1996 version of NEC. It seems that table has been revised. Anyway, my concerned in operating temperature less than 90 0C for MV equipment.

Thanks,

Mohsen
 
Re: Cable sizing

All listed MV equipment has a 90C rating. I think that most all MV equipment Has this same rating
 
Re: Cable sizing

OK, This is what I initially came up with but I am wondering if there is any explanation about that in the NEC says "all MV voltage equipment should have a minimum operating temperature as 90 0C"

Thank you
 
Status
Not open for further replies.
Top