# 310.15(B)(2)(c)



## jar546 (Sep 13, 2010)

Anyone else ask for the ambient temperature calculations?

This is a short one but I have had a few that were several hundred feet.


----------



## jar546 (Sep 13, 2010)

No commercial electrical guys out there?

Do you do the calc at plan review or do you ask for that info from the electrical engineer that designed it?

I have found out that most EEs are not aware this new section in the 2008 NEC exists.


----------



## 480sparky (Sep 13, 2010)

Length of the run has no bearing on any calcs.  And it's hard to assist you in any calcs without any information.

Other than that, I would simply build any calcs into my bid.  The plans will tell you what is needed, all you need is to design the system on paper, using T310.15(B)(2)© to calculate any temperature 'adder'.


----------



## chris kennedy (Sep 13, 2010)

But what do you base those calcs on? This is a helpful link to find the design temps in you area from the guys that promote derating to sell larger wire.   But I do use this same table for my calcs.

Design temps.

BTW Jeff, do you know where they get those sporty end caps for the uni-strut?


----------



## jar546 (Sep 13, 2010)

Don't know where they got those caps.  It is a Verizon Wireless install if that helps you to contact someone.


----------

