sw900 vs hksunwin controller (no speed displayed)

[jimmyhackers]

im trying to get my sw900 to work with my 1500w hksunwin controller.
https://www.ebay.co.uk/itm/391359478200

i have connected the ground (black), positive (red), security (blue), and recieve (green) wires.

i havnt connected the transmit (yellow) i dont think i need to/am not sure what to connect it too.

thing turns on..sends the power to the "on" wire on my esc. bike works.

but there is an error 10 (communication recieving problem) and the speed will not display.

the only reason im putting it back on my bike is for the speedo/mileage counter.

my green recieve wire is connected to my controllers green lcd display wire.

really not too sure what to do

 

[docw009]

Your hksunwin doesn't support an LCD disolay.

The SW900 dispaly and others like it are self-supporting. All they need to power up is battery and ground. When they get that, you can power them up and they will raise the blue lead to the battery level.

Meanwhile, all that most controllers need to power up is battery, ground and the corresponding blue (it may not be blue) lead raised to battery level. Often they will then operate with a default PAS and throttle is supported.

You provided all of the above with your wiring, and both components powerup, but they don't communicate and never will. Sometimes people have controllers that have the same connector pinout, with working transmit/receive lines. Unless both components have the same communications protocol, they still will not work. You cannot get an SW900 to work with a KT controller, although they have the same connectors.

 

[jimmyhackers]

thank you for the info, i had a terrible feeling it was something like different protocol.

the green wire out my hksunwin controller is labelled lcd display though, and also as "speed line" in the selling description. So it must work with something.

any ideas what display will work with it? i would ask the ebay seller but they dont seem to accept messages

 

[E-HP]

thank you for the info, i had a terrible feeling it was something like different protocol.

the green wire out my hksunwin controller is labelled lcd display though, and also as "speed line" in the selling description. So it must work with something.

any ideas what display will work with it? i would ask the ebay seller but they dont seem to accept messages

I had always thought that the speed wire, or controller wire in this case, provides a hall sensor signal output for adding a speedometer (not sure if it would work as an input to an old bicycle speedo, but maybe).

 

[amberwolf]

I know this is an old thread, just dropping this here for future readers taht come across this:

It is likely that the speed wire on the HKsunwin controller in this thread is like that of many "scooter" controllers--a repeater for either one of the hall signals, or of a phase wire, so giving pulses for every magnet pass (though possibly a pretty noisy signal under high motor loads, especially at startup from a stop or other low-speed high-load situations).

The simple "scooter" displays / LCDs just display the battery level in some way and the speed, and have no communications with the controller, unlike the more sophisticated stuff.

You'd want to test with at least a voltmeter to verify the output voltage from it before connecting it to anything, since a phase wire "repeater" can have pulses of battery voltage on it, while the hall repeater would be logic-level (in the 0-5v range, usually).


Since the signal would usually be a pulse for every pole pair in a hubmotor, a bicycle speedo (that expects one pulse for every wheel rotation) will read several to many times too high (since most hubmotors have several to a couple of dozen pole pairs).

Electronics can be made to divide that down to one PPWR but it's much simpler to just use the sensor and magnet that come with the bicycle speedo, if you are already going to use one.