Electrical question about amp rating: service entrance versus feeder

[Danno1]

When I wired our new house all cables were rated at 90 and I guess I don't know how a piece of wire gets a 90 or an 80 or a 70.

It's based on the type of plastic the insulation is made of.



.

 

[teejk]

Thanks...that's what I was thinking since the conductor is what it is. My guess is that most modern wire is rated at 90 but still makes sense to check it when you buy it or when you pick up an old coil.