Sizing Conductors

[Dennis Alwon]

Bare busbar has no insulation temperature rating.

Doh-- of course......:ashamed1:

 

[Carultch]

Bare busbar has no insulation temperature rating.

Well I'm sure it does have a temperature limit that is a safety margin below the melting point of all metals involved.

Tin melts at 230C
Aluminum melts at 660C
Copper melts at over 1000C
And there is also a consideration of the non-metallic insulating mounts for the busbar, which might melt or burn colder than any of the above temperatures.

 

[Smart $]

Well I'm sure it does have a temperature limit that is a safety margin below the melting point of all metals involved.

Tin melts at 230C
Aluminum melts at 660C
Copper melts at over 1000C
And there is also a consideration of the non-metallic insulating mounts for the busbar, which might melt or burn colder than any of the above temperatures.

Quite true... but there is no industry rating that correlates with termination temperature limitation factors of 110.14(C).

When busbar is integrated with enclosed equipment, under industry testing standards it inherits the limitation given to the entire enclosure. I question the merits of this assumption in certain scenarios, but not in others. As we all know, NEC requirements and UL listing standards are fashioned with blanket coverage in mind... knowing full well there are gray areas.