Hello.
I want some input from the community on what happened to me this week. I have a 2004 Nissan Sentra converted EV and it has been working fine since the conversion for about 13 months (it had to be 13), but this week at a red light I lost the brakes almost completely

. I was lucky enough to have space from the car in front, and the hand brake assisted good enough to stop in time since I was in a flat road. The reason was that the fuse of my vacuum pump burned and then I lost the assisted braking, and considering that I have 1,400 lbs. of lead-acid battery weight…
This got me thinking of what may have happened because of a tiny little cheap fuse

. The city where I live is all flat, but if I had been in a downhill road I don’t think I would have been able to stop the car in time.
I have had for a while a sensor that disconnects the pump when there is enough vacuum, and I am not sure why I installed a fuse that was only 5 amps (inline fuse not part of the pump), but I replaced this fuse with a 15 amps and everything seems to be working fine again, but I was wondering if people living in hilly places put an emergency secondary vacuum pump just in case.
A gasoline engine can also fail and lose the brakes, but at least there is compression in the engine to try to do something and they do not weight as much as electric cars (especially conversions). Also in gas cars, if the transmission is still engaged I figure it will generate some vacuum even if the engine is dead.
I am interested in hearing if it is common to put some kind of emergency braking in conversions because at least in DC, there is nothing to slow down the car if the brakes fail. I don't have a vacuum tank. Is this something that may have helped? an alarm if the vacuum gets below some value? Other ideas?
Jose