melted blade fuse

jimmyhackers

Pedelecer
Feb 18, 2015
91
14
36
noticed this with my golf trolley bikes and its happening again with my hub motor

the main fuse gets really hot and melt/warps its casing but doesnt blow.

google says its cheap fuses. i concur with this

few questions.

1. is this heat loss going to be a noticeble drain on efficiency/power? its a 40A fuse
2. is it blade fuses in general that get hot so a glass type would be better? (the kit came with a 40amp glass which im not using currently)
3. would i be better going to a 45 or 50amp fuse?

thanks in advance
jim
 

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
1,076
Devon
The mini blade fuses are not capable of 20 amps. They might sell 30 and 40a fuses, but the housings melt (and bypass the fuse!) a great deal lower.

I have a large melted hole in one of my lithium batteries caused by a fcucking device that I installed for protection!

The full sized ones are a little better, but not much.

Some say that if you have a BMS you don't need a fuse.

Conclusion: Good quality fuse, or no fuse. Middle ground is probably more dangerous.
 

jimmyhackers

Pedelecer
Feb 18, 2015
91
14
36
update: on closer inspection i found the fuse holder to be at fault.

the controller side terminal in the holder was loose meaning for arcing etc. quick squeeze with the pliers and all is good. fuse runs ice cold.

went for an hours blast and it feels more torquey with a 2mph speed increase. now hitting 28mph uphill 32, on a flat and 35mph downhill :)

thanks for the help anyways