310.15(b)(1)(1) vs 310.15(b)(1)(2)

[david luchini]

Well, more clarity, this question:
Two outdoor installations. Both single insulated, same size cable in free air. But one ampacity on base 30C ambient and other 40C base ambient. Ampacity of each cable?

At what ambient temperature are the installations.

 

[Deltaforce]

At what ambient temperature are the installations.

40C

 

[david luchini]

A single #1 awg THWN copper conductor in free air in a 40C ambient will have an ampacity of 171.6.

A single #1 awg Type Z copper conductor in free air in a 40C ambient will have an ampacity of 293.

 

[Deltaforce]

A single #1 awg THWN copper conductor in free air in a 40C ambient will have an ampacity of 171.6.

A single #1 awg Type Z copper conductor in free air in a 40C ambient will have an ampacity of 293.

So the installer not mix up the two

 

[david luchini]

So the installer not mix up the two

What?

 

[Deltaforce]

What?

Over-rating or under-rating cable size may if temperature correction factor table wrong use

 

[david luchini]

Over-rating or under-rating cable size may if temperature correction factor table wrong use

What?

 

[Deltaforce]

What?

For example use 86F correction factor table T310.18 application by mistake