A 100 amp Victron Mega fuse blowns at 250amp accroding to this video (289) Testing 100A Fuses with 100A of current. - YouTube
I am concern then how to choose the correct fuse for a 100a wire capacity, a 60amp?
asked
Victron Mega Fuse slow blown issues
Look at there time-current characteristics for this type of fuses: https://www.littelfuse.com/~/media/automotive/datasheets/fuses/passenger-car-and-commercial-vehicle/bolt-down-fuses/littelfuse_mega_datasheet.pdf
I would say they are very much in range and work as expected. Comparing Mega fuses with ANL, Midi or the Erayco fuse/breaker is not expedient because they have a completely different characteristic.
We had this topic a few months ago with the same video.
Unfortunately I can't find that topic right now.
A 100A fuse should be able to carry 100A for a infinite time, it should not blow at 100A.
I guess he first fuse and that breaker tested in that video will also blow at 90A or less if that current runs for a while and ambient temperature is a bit higher.
The guy in the video is rising the current to fast, he should go up in 5A steps and let it run for 5-10 minutes.
It is also written in some comments below that video.
@SebastianLehmann a rough rule of thumb. Slow blow fuses will not blow until short term current is twice the rated value. But bear in mind the other advice in this thread. All fuses are not equal. The first fuses tested were clearly substandard.
And remember the purpose of abuse is wiring protection, not the components (unless you have specific very fast fuses designed for this, and even then they are often inadequate in some circumstances). Equipment protection is by design.
