bafung bpm motor leads

[chisixer6]

I am thinking of getting a Bafung BPM motor from greenbike kit. From pictures I seen on the lead wires, it seem to show only Halls wire and no phase wire, are these somewhere else?


http://www.greenbikekit.com/index.php/electric-motor/bldc-bpm-500w-36v.html

thanks in advance

Jerry

 

[amigafan2003]

Eh? Since when did a motor have 4 pahse wires?

I can see three phase wires and a bundle of hall wires in that pic.

They normally bundle the hall wires up and wrap the ends in electrical tape. The phase wires are the ones that have bullet connectors.

 

[d8veh]

I am thinking of getting a Bafung BPM motor from greenbike kit. From pictures I seen on the lead wires, it seem to show only Halls wire and no phase wire, are these somewhere else?


http://www.greenbikekit.com/index.php/electric-motor/bldc-bpm-500w-36v.html

thanks in advance

Jerry

The phase wires are very thin. In fact they don't look thick enough, but don't let that put you off unless you want to go with more than 30amps (standard 12 FET controller Con121 is 30A). Get the whole kit. They're really good value and the motors are strong and reliable. If you want a bare motor, the Bafang CST is even better as it takes a standard cassette.

 

[chisixer6]

d8veh;

ok thanks..I will get the BPM motor, I already have the con121 controller.I found out that the BPM come sensorless too, but I am going to use them sensored.

thanks

 

[d8veh]

d8veh;

ok thanks..I will get the BPM motor, I already have the con121 controller.I found out that the BPM come sensorless too, but I am going to use them sensored.

thanks

Always better with sensors.
The standard phase wire bullet connectors are not good enough. The plastic covering melts, which can cause them to short out. There's the additional waterproof connector at the motor, so you can solder them together, or better still, soilder them directly to the controller PCB after unsoldering the old ones. Rather than unsoldering the hall connections, which is a bit tricky, you can cut them above the pcb and join them to the other part by soldering them inside the controller box.

 

[-dg]

Always better with sensors.
The standard phase wire bullet connectors are not good enough. The plastic covering melts, which can cause them to short out. There's the additional waterproof connector at the motor, so you can solder them together, or better still, soilder them directly to the controller PCB after unsoldering the old ones.

I have an SWXK that seems fine sensorless, but I'm thinking about a BPM for another build and can go either way, so why "always better with sensors"?

I like the idea of soldering the waterproof phase cable right to the board. Very clean. The big wad of excess wire and huge craptastical connectors on my first bike is starting to really annoy me. I'm tempted to unsolder all the throttle and switch cables and just solder in a short mini-din keyboard extender cable and use a keyboard cable to get from the controller to the bars. Or just to replace all the janky oem connectors with something like servo connectors and just tape them up. Any better ideas on this?

 

[chisixer6]

I am going to have to bow out of the BPM motor, I believe it is too large for my current build (twin 16" wheels). for this bike I am going to one of the smaller diameter motors. I am not sure if a BPM would fit inside a 16" 305 rim, but if it did, the radial lacing should be super strong, considering the spokes will probably be a few inches long. I am not looking for a high speed setup, my 901c motor with 5 winds in a 20" wheel, should propel me, if it doesnt kill me first, to some decent speed.

 

[d8veh]

I have an SWXK that seems fine sensorless, but I'm thinking about a BPM for another build and can go either way, so why "always better with sensors"?

Smoother and more efficient. The Bafang 250w motors do run OK sensorless, and the BPM is also not bad, but it doesn't cost anything extra for sensors, so you might as well use them and get the advantage - especially if you get a controller that has auto-detect and can switch modes like the KU93 or K123 from BMSBattery or equivalents from other suppliers.

 

[mlt34]

d8veh;

ok thanks..I will get the BPM motor, I already have the con121 controller.I found out that the BPM come sensorless too, but I am going to use them sensored.

thanks

Always better with sensors.
The standard phase wire bullet connectors are not good enough. The plastic covering melts, which can cause them to short out. There's the additional waterproof connector at the motor, so you can solder them together, or better still, soilder them directly to the controller PCB after unsoldering the old ones. Rather than unsoldering the hall connections, which is a bit tricky, you can cut them above the pcb and join them to the other part by soldering them inside the controller box.

nice mod, d8veh. Is that a BMSbattery controller or did it come from greenbikekit? I haven't yet made an order from greenbikekit but I've had at least a dozen from bmsbattery. What's the deal with that anyways, are they basically the same or did someone jump ship and start greenbikekit?

 

[d8veh]

The controller is the KU123 from BMSBattery. It's the same as the one from Greenbike kit. My theory about Greenbike kit is that one or more jumped ship from Bmsbattery, as they seem to have access to their customer database. I've ordered from both and now that BMSBattery have upped their game, there's nothing to choose between them.

If you get one of these controllers, don't use the standard bullet connectors for the phase wires. They get hot and melt the insulation, which could be nasty.They're alright at 25 amps and less.

 

[-dg]

I have an SWXK that seems fine sensorless, but I'm thinking about a BPM for another build and can go either way, so why "always better with sensors"?

Smoother and more efficient. The Bafang 250w motors do run OK sensorless, and the BPM is also not bad, but it doesn't cost anything extra for sensors, so you might as well use them and get the advantage - especially if you get a controller that has auto-detect and can switch modes like the KU93 or K123 from BMSBattery or equivalents from other suppliers.

I measured the phase wires in the "waterproof" motor cable supplied by greenbikekit with my sensorless SWXK and also a sensored cable that they sent by mistake.

Diameter of one phase wire including insulation:

Sensored 1.8mm
Sensorless 1.9mm

So it looks like the sensorless cable maybe able to handle more current. I'm not sure at what level this will matter.

 

[d8veh]

That's a good point if you're going over 30 amps.