Ampacity for for 105°C and 125° Low voltage wire

[GlenB]

Hello,

In the telecom industry we deal primarily with 105°C and occasionally 125°C wire. The NEC tables do not provide any ampacity ratings for these conductor temp's. We have researched this many times and have always found conflicting information.

Is there an NEC approved Formula/Table that will provide the Ampacities for this wire?


Glen Bell
Purcell Systems

 

[Dennis Alwon]

There are more tables past 310.15(B)(16) which have higher temp rating. For instance 310.15(B)(18) has temp. up at 250C

 

[GlenB]

There are more tables past 310.15(B)(16) which have higher temp rating. For instance 310.15(B)(18) has temp. up at 250C

Yes but they do not cover 105°C or 125°C

 

[tom baker]

Try contacting the manufacturer of the wire...

 

[Dennis Alwon]

I found this but...
https://www.coonerwire.com/amp-chart/

 

[don_resqcapt19]

If the terminations are covered by the NEC, it really doesn't mater because, in most cases the circuit ampacity will be limited by the 75°C rating of the termination at the equipment.

 

[pv_n00b]

NEC 310.15(C), conductor ampacity can be calculated under engineering supervision. That's about all the NEC has to offer for those temperature ratings.

 

[kingpb]

NEC 310.15(C), conductor ampacity can be calculated under engineering supervision. That's about all the NEC has to offer for those temperature ratings.

But as Don said, it doesn't matter what ampacity you calculate. The current is going to be limited to whatever temperature will cause the cable, and thus termination to reach 75 Deg C.