has anyone blown the blade fuse, is it needed?!

[neilhapgood]

hi all,

my TSDZ2 set up has had an increasingly common issue with losing power, it fixes if I wiggle the wires coming out of the battery mount.

On closer inspection the issue is one of the wires that comes out of the blade fuse, because of how the fuse sits the wire comes out a 90 degree angle and is pushed up against the side of the housing, I think I have damaged it when I put the bike on top of the car and tightened the arm to hold it in place on the wire and probably put too much strain on it.

I'm wondering how important the blade fuse is, I've never heard of one blowing so wondering if the chances of needing one is slim?

If this is the case, or if a need a quick fix to get me home, could I just cut it out and re-join the wires with a connector?

Many thanks

 

[Nealh]

It is there to prevent power surge or heat damaging the controller.
I have had a blade fuse and holder melt on 20a hub controller kit with a 44v battery.

 

[richtea99]

Never bypass a fuse permanently. They spent a little extra money putting in it there. If they could have avoided it, they would have!

Is there a way to remove the original fuse and put a replacement one in, but in a more convenient place? Then your weak connection point is fixed, and you've still got circuit protection.

 

[Nealh]

Batteries that use four or more cells in a parallel may have 10a rated cells so possibly 40a or more, most BMS allow for some over current over and above the continuous rating of the bms which may be 15, 20 or 25a, the fuse usally is at the same or approx 5a higher then the continuous rating. Should the BMS fail and deliver far more current either the wiring may get very hot or burn or the motor controller will fail.
In my case the current was far more then the continuous rating and the fuse holder melted in to a mash of plastic and the fuse also.

 

[neilhapgood]

richtea and nealth, thanks so much for your input, I put in a new blade fuse holder and its working fine now, thanks again

 

[Bikes4two]

Just a minor point in that a blade fuse of the type referred to will not directly prevent a power surge or an overheat situation.

In the case of a power surge, excess current (as in above the fuse's rating) causes the fuse element to heat up and then part/blow after some milliseconds and the power surge is stopped, hopefully before too much damage to battery, motor or controller etc has occurred.

Excess current flowing invariably heats components up of course and hopefully the fuse blows before damage occurs.