Hi Demetris and
to the forum.
I'm not sure whether the MPIII's controller has a thermistor fitted or not, although there is one component that looks a bit like a thermistor, but as it is labelled as C34 on the circuit board, I'm guessing it's just a capacitor.
There are eight wires in the external cable which connects directly to the controller:
- Thick Red wire: Battery + Supply
- Thick Black wire : Battery - Ground
- Thin Green wire labelled "sb" = Throttle Hall Sensor Output Signal (0-5V)
- Thin Blue wire labelled "br" = Signal from Brake Lever Switch (Grounded when brakes are applied)
- Thin White wire labelled "+5" = 5V Supply for Throttle Control and Pedelec Sensor
- Thin Red wire labelled "xun" = Cruise Control Signal (Grounded when Cruise Button is pressed)
- Thin Black wire labelled "rx" = Reverse and programming Signal (Connect to Ground to Reverse motor direction)
- Thin Yellow wire labelled "pas" = Output Signal from Pedelec Sensor
If you want to fit a separate temperature probe inside the motor, the best place to mount it would be against the windings themselves, as I would expect the windings to get hotter under continuous high current loads than the controller itself.
Regarding the logic voltage, there are actually two low voltages that I have noticed on the controller;
The first is the obvious 5V supply, which is used for powering the Hall Sensors, Throttle and Pedelec Sensor.
The second is a 12V supply, which I suspect is used to power the switching of the Gate connections on the
MOSFETs, as a higher Gate voltage should produce a lower voltage drop between the Source and Drain contacts, allowing high current to be switched more efficiently, hopefully producing less heat too.
Alan
