I'm replacing some light fixtures in my house, and the existing cable coming out is very old. I was able to make out the stamp along the length, and it's 12/2 NM cable, rated to 60C. It's got a neutral, hot, and a ground.
Newer cable, I've come to find out, is NM-B, which has a 90C rating. The light fixtures I've picked up are labeled that they need a 90C minimum rating.
So, I take it I've got to replace at least the cable that connects to the light. My plan is to pull out the existing NM cable in the attic, and splice in some NM-B, which I will run to the fixture.
Is there anything wrong with doing this? Do I need to run a new NM-B cable from the breaker?