What is an R-Rated Fuse?

[fuse_puller]

Another simple question for you guys,

What is an R-Rated Fuse? Sounds like a movie rating but I doubt the two have much in common.

--- R-Rated Fuse ---

Thanks!

[Cheller]

I have to admit, I had to do some research on this fuse question. It goes to show, you learn something every day.

R-rated fuses are typical used to protest medium voltage motors and modern motor controllers. They are designed to protect electronics that are sensitive to large short circuit currents.

There are NEMA Standards for R-rated fuses. It requires that they open within 15-35 seconds when exposed to current that is 100 X the "R" rating. That is specifically RMS current.

(To me they seem like they would classify as somewhat of a semiconductor fuse, but that's just my opinion.)