100% Circuit Breaker Confusion

[xguard]

I've found circuit breaker catalogs and websites state this or something similar:

"The NEC (or UL in one case) allows the breaker to be rated at 100% of its frame size in an assembly, provided that 90 degree C wire is applied at 75 degree C ampacity."

Does this mean 90 deg C wire must be used?

Or can you can still use 75 deg C wire at it's 75 deg C rating?

 

[iwire]

I've found circuit breaker catalogs and websites state this or something similar:

"The NEC (or UL in one case) allows the breaker to be rated at 100% of its frame size in an assembly, provided that 90 degree C wire is applied at 75 degree C ampacity."

Does this mean 90 deg C wire must be used?

Or can you can still use 75 deg C wire at it's 75 deg C rating?

You must use at least 90C conductors but only load them to the 75 C ampacity.

They are using the conductors as heat sinks to pull heat out of the breaker. (Or at least not put heat into the breaker)

 

[Carultch]

I've found circuit breaker catalogs and websites state this or something similar:

"The NEC (or UL in one case) allows the breaker to be rated at 100% of its frame size in an assembly, provided that 90 degree C wire is applied at 75 degree C ampacity."

Does this mean 90 deg C wire must be used?

Or can you can still use 75 deg C wire at it's 75 deg C rating?

Most single conductor wire today is 90 C rated anyhow. What kind are you intending to use?