Front hub 48v motor for very hilly area

vfr400

Esteemed Pedelecer
Jun 12, 2011
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3,993
Basildon
On opening my controller there is a small PCB under shrink wrap that appears to be connected to the lighting output. What is on that PCB is a mystery but I am guessing the transistor you mention.

My idea was to use the light output wire as the low voltage side of an optical relay as per the ES thread I linked above and use 12v from a DC/DC converter to power the lights. As I want to also be able to ride my trike with the motor wheel removed the lighting circuit will optionally be powered by a 3S 5000 mAh Lipo brick.

Projected are:

- always on head and tail lights
- brake light, nothing fancy, just a second rear LED light that is turned on by the brake sensors (possibly mounted high up for SUV's...)
- indicators, mostly useful in "warning" mode - all flashing for riding in town where there are no cycle paths but a motorcycle turn signal, switch will be mounted too
- hi/lo beam headlights, again nothing fancy just a second headlight adding 70-80 lux when on the open road. This is the one I want to be able to turn on from the controller button.
If it's a separate PCB, it's probably a DC/DC converter. If not that, it must be a decent MOSFET to switch higher pose lights. What voltage do you get on the connector? What controller is it?
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
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The European Union
KT36/48SVPRMB-SJT02LB 9 FET bluetooth sine wave controller

Can't turn on the light because I don't have it connected to an LCD yet.
 

BidelloZ

Pedelecer
Jun 25, 2019
76
6
On opening my controller there is a small PCB under shrink wrap that appears to be connected to the lighting output. What is on that PCB is a mystery but I am guessing the transistor you mention.

My idea was to use the light output wire as the low voltage side of an optical relay as per the ES thread I linked above and use 12v from a DC/DC converter to power the lights. As I want to also be able to ride my trike with the motor wheel removed the lighting circuit will optionally be powered by a 3S 5000 mAh Lipo brick.

Projected are:

- always on head and tail lights
- brake light, nothing fancy, just a second rear LED light that is turned on by the brake sensors (possibly mounted high up for SUV's...)
- indicators, mostly useful in "warning" mode - all flashing for riding in town where there are no cycle paths but a motorcycle turn signal, switch will be mounted too
- hi/lo beam headlights, again nothing fancy just a second headlight adding 70-80 lux when on the open road. This is the one I want to be able to turn on from the controller button.
Does it look like this PCB on my controller?

Mine was a not connected to the light output.

In fact the yellow and orange wires that are referred to as “head light” on the wiring schemes are just connected straight to the battery terminal.
 

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vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,993
Basildon
Is it a sensorless controller? If so, that's to detect the motor position for timing because you don't have hall sensors. It takes a back emf pulse from the phase wires and converts it to a 5v pulse which it sends back to the controller's hall wire connection points so that they can use the same main board as the controller for sensored motors.

It has nothing to do with lights and isn't connected to the lights connector, which is a direct feed off the battery.
 
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