This video covers a lot of it.
“…a 20A MAXI Fuse experiencing an overload of 100A will open in about 0.5 seconds. At 40A, the same 20A MAXI Fuse would open in about 9 seconds.”
“… a fuse with a current rating of 10A is not usually recommended for operation at more than 7.5A in a 25 ̊C ambient”
This is an excellent document that anyone doing wiring should definitely read - as well as their Automotive Transients appnote on all the nasty voltage spikes etc. that can occur in cars.
The Bussmann ATC Fuses datasheet also contains useful info.
This video gives a great explanation of how fuses work and also why cheap / unbranded fuses should be avoided.
And this comment on Hackaday about how hostile automotive environments are to electronics:
As someone who was a automotive tech for 3 years, I have to stress that “Dude”s comment above is really important in that the automobile electrical system will kill your design; it’s only a matter of when, not if. It’s the 90volt transients from the alternator that do it.
Input power conditioning must be used. The common method is a 100 ohm 5 watt resistor in series with the input and a fuse. This connects to a 24V Zener diode of 1W rating.
The main failure mode: the Zener shorts out and blows the fuse so only these need to be replaced to repair the instrument. The fuse is usually just a thin (by design) copper track segment about 5mm long on the PCB. It should blow when shorted across 12V without burning the rest of the pcb, and is repaired by soldering a equivalent piece of thin copper wire across the burn out segment.
Terry Porter