MP4 turn controller on/off

[Haggan]

I got a 48V battery without  on/off button so engine and controller is on when plugging in the battery. Is there any way to turn off the controller or do I need a turn off button on the battery cables?  on Another e-bike setup I could turn on/off the controller with the "mode" button. But the MP4 display is always on.

If not switching during load what is the recommended switch spec. I read a lot of precharge and stuff. Is there any good switch that has all the good functions?

cheers

[Bikemad]

Unfortunately there is no way of turning the controller off without interrupting the battery supply.

The easiest way is to use a 16 Amp double pole single throw switch on the positive battery wire and connect both poles in parallel to safely carry 40+ Amps @ 48V:




A momentary push switch and a 30 Ohm resistor can be used to pre-charge the capacitors in the controller before operating the switch to eliminate any arcing at the switch contacts:



Check out this post for more details on the precharge resistor.

Alan
 
EDIT: Broken links repaired

[Haggan]

Hej

Thanks! I thought the same to  use a switch in parallel. I just ordered a 20A switch with no light.
Will a 33 Ohm Metaloxide film resistor 3W do the trick to precharge? 

Cheers

[Bikemad]

That resistor should be fine through a momentary push switch, but if a continuous switch was used, the resistor could become overloaded if the throttle was operated with the power switch turned off and the resistor alone supplying all the current to the controller.

Alan
 

[Haggan]

Yes. Also order push button.

Thanks for your help.