Carrera E Vengeance - Bafang BFSWX02 36V250W (12) & S866

[essex_chris]

I've had a 2019 Carrera Vengeance Ebike for a year nearly. Bought it secondhand last summer. Ben very please with it.
Recently had a problem where the controller seemed to die and there was a short with the battery connector. Fixed that - cut off corroded battery terminals and rewired it to use two others instead. But that's when I found the controller was dead. So purchased some bits off Amazon UK to get thigs going again.

I bought the following;

Motor controller & LCD

https://amzn.eu/d/73wpfqN

Thumb Throttle

https://amzn.eu/d/8htFZxC

The stock motor on my 2019 Vengeance E is a Bafang BFSWX02 36V250W (12)

At the moment i have wired it all up - some is soldered and some connector blocks - once i have it all done properly i will likely solder all joints, heatshrinkg everything and siicon seal up - the new controller doesn't fit into the old space beneath the battery.

Initially having matched up the wires based on the colours and the wiring diagram - i could hear the motor turning but freewheeling so appeared to be running the wrong way round - one jumper type connector on the leads coming out of the controller and that was sorted.

What i'm really not sure about now is what settings to use on the controller regarding magnets or zero start. I also can't work out at present where to attach the 3 wire pas sensor - the plugs are different but it's no problem i can solder them together ok.

Found the manual referring to brown and black lines - but theres a purple cable on the controller which when connected worked and meant that once powered on the wheel spins - but it's very low power. Though it does adjust when pushing the + and - for adjusting the PAS level.

Presently as soon as I power on using the display the wheel starts turning driven by the hub motor - but there is little or no power. If i turn up the PAS on the display it has more power but it's very neutered and wouldn't be able to push the bike and a person.

After initially wiring up the battery terminal connectors, the blue/yellow/green motor phase wires and then the 6 cable for motor hall sensors i could hear the motor spinning but figured it was the wrong way.

So at the moment i have the LCD connected - the motor, but not the PAS or the throttle. Have tried hooking that up to the connectors based on the A4 maual that came with the S866 but not been able to get any further.

I have a 3 pin throttle from amazon with black/red/green wires - nothing corresponding on the leads out of the controller. Ideally i'd like to set it up with both the pas and the throttle. If possible i'd like to set it it up for more than 25.5kph - even at my weight the stock setup felt it could do more - but was limited.

The Vengeance has brake connectors with juliet cables - but not sure about wiring that up.

I have a feeling that it's all to do with the settings on the LCD for how many magnets and power settings etc but i can't work it out. I can't find a manual for the BFSWX02 and am reluctant at this stage to open it up and take a look. Though if i have to it'll be a good opportunity to do some maintenance on it.

Thanks in advance

 

[essex_chris]

These are just some photos of the controller and wiring at present.

The original PAS sensor is 3 wire, as is the throttle. Red white black or red white green but both 3 wire.

 

[AGS]

I can help with some of it.

Your motor has 20 magnets and a reduction ratio of 5:1, so P07 should be set to 100

 

[essex_chris]

This is copied and pasted from a PDF manual for the S866. My paper one has P21 and P22 also.

I've tried changing various settings like the zero or non zero start, or the number of magnets, and resetting the controller back to default - but in all cases the bike when powered on turns the wheel - i can't turn it of but changing using the + and - buttons does make it speed up and slow down

"4.Setting
P01: backlight brightness, level 1 is the darkest, level 3 is the brightest;
P02: mileage unit, 0: KM; 1: MILE;
P03: Voltage level: 24V, 36V, 48V, 60V, 64V Default 36V;
P04: Sleep time: 0, no sleep; other numbers are sleep time, range: 1-60; unit
minutes;
P05: Power assist position: 0, 3 file mode:
1, 5 file mode:
P06: Wheel diameter: unit, inch; accuracy: 0.1;
This parameter is related to the display speed of the meter and needs to be
entered correctly.
P07: Number of speed magnets: Range: 1-100;
This parameter is related to the display speed of the meter and needs to be
entered correctly.
If it is a normal hub motor, directly input the number of magnetic steel;
If it is a high speed motor, it is also necessary to calculate the reduction ratio,
input data = number of magnets × reduction ratio;
For example: motor magnet steel number 20, reduction ratio 4.3: input data:
86=20×4.3
P08: Speed limit: the range is 0-100km/h, 100 means unlimited speed.
The input data here indicates the maximum running speed of the vehicle: for
example, input 25, indicating that the maximum running speed of the
vehicle does not exceed 25km/h; the driving speed is maintained at the set
value.
Error: ±1km/h; (both assist and speed limit)
Note: The value here is based on kilometers. When the unit setting is converted
from kilometer to mile, the speed value of the display interface will be
automatically converted to the correct mileage value, but the speed limit
value data set at this menu under the mile interface. No conversion,
inconsistent with the actual display mile speed limit value;
Note: The P09-P15 menu is only valid in the communication state.
P09: zero start, non-zero start setting, 0: zero start; 1: non-zero start;
P10: Drive mode setting 0 : Power drive (the booster position determines how much
power is output, and the switch is invalid).
5
1 : Electric drive (driven by the rotary handle, the power assist position is invalid at
this time).
2 : Power assist drive and electric drive coexist simultaneously
P11: Boost sensitivity setting Range: 1-24;
P12: Boost start strength setting Range: 0-5;
P13: Power magnetic steel disc type setting 5,8,12 magnetic steel three types
P14: Controller current limit value setting Default 12A Range: 1-20A
P15: Controller undervoltage value
P16: ODO clear setting Long press the up button for 5 seconds ODO clear
P17:0: cruise is not enabled, 1: cruise is enabled; auto cruise is optional (only valid for
protocol 2)
P18: Display speed ratio adjustment range: 50%~150%,
P19: 0 gear enable bit, 0: 0 gear, 1: 0 gear
P20:0: Protocol No. 2 1: 5S Protocol 2: Alternate 3: Alternate
四、Introduction to buttons and display interface:
"

 

[essex_chris]

I can help with some of it.

Your motor has 20 magnets and a reduction ratio of 5:1, so P07 should be set to 100

Thank you for this. Just heading out for lunch but will take a look at that when I return.

 

[saneagle]

Thank you for this. Just heading out for lunch but will take a look at that when I return.

You have a geared motor with an internal speed sensor. That's assuming that the motor cable shown in your photo is OEM. It means you have 1 or 6 magnets for the speed sensor and p07 should be set to 1 or 6, not 100. The speed display on the LCD will show which of 1 or 6 is correct. Try 1 first.

If the motor is turning backwards, that brown and white wire might be the reversal function. Measure the voltage between ground and each. If you get battery voltage on one, forget it. If you get 5v on one, then clip a ca. 5k resistor between them and see if it reverses, then if that works, you can just join the wires to make it permanent. Your photo isn't clear. Some Brainpower controllers have two green wires that clip together to do the self learning, which reverses the motor each time you do the procedure. Unclip them when you get it right.

P09 is throttle function - independent or only when pedalling
P10 is whether only the throttle is active or both throttle and PAS.
P13 is number of magnets in PAS disc.

 

[AGS]

Wrong. P07 should be set to 100 for his motor not 1 or 6.

 

[essex_chris]

Apologies for the delay, been so busy the bike has taken a back seat.

The motor is the stock Carrera Vengeance Espec 2019 - it is marked on it with Bafang BFSWX02 36V250W (12) and has a half inch 9pin Julet connector. The wires in the photos are just the bare end of that connector. Thank god for it as i would have to identify which wire is which and also would have major trouble in the event of removing the rear wheel for a flat ro to replace a spoke.

P09 is described as zero start - non zero start in both the a4 manual and a pdf copy i found online.

Should i be wiring in the Throttle and the PAS sensor to the same 3 wires from the controller? I've tried each individually and both at the same time - all while experimenting with the P01-P20 settings but so far i am unable to get the motor to do more than engage briefly. Like there's a pulse but no real power engaged.

I have 27.5 inch wheels. 36v 8ah battery. There are julet connectors hooked up to the brake levers - these and the old 790 handlerbar led indicator were wired into a 6pin julet connector through a 3 way splitter at the handlebar end - at present they're not connected at all and i hoped i would be able to simply leave them unused.

There are two green wires which were the ones i clipped together which i think resolved the motor thte wrong way issue - but once it works i should disconnect those as otherwise itll relearn again each time i power on?

I didn't want to bombard with photos - but if i should get good clear photos of anyting in particular please let me know. I have the manual that came with it - two sided A4 with the wiring shown and the P01-22 options listed.

At the minimum if possible i'd like to get things running again using the PAS at stock power settings - just to get back using it again.
If it is possible to get a throttle going great, and if i can increase the power from 250w and get a bit more out of it that'd be great too.
I am semi in the market to get another bike which has 500W+ but i'll worry about that once i get this back to being a daily commute bike .

Thanks for your help

 

[saneagle]

The green wires are the self-learning ones that identify the hall and phase wire sequence to make the motor work. Each time you do the self-learning procedure, the motor changes direction. Now that you have it right, leave them disconnected.

You cannot wire the throttle and PAS to the same connector. They work differently.

Brake switches are optional as far as the bike working, but some crappy controllers cause run-on after you stop pedalling when using the pedal assist, so that when you want to slow down with the brakes, the motor is working against you. In that case, you need to get the brake sensors working, but leave them until everything else works.

Throttle is very good for testing a new installation because you have the least number of possibilities for variables.

It sounds like you've sorted it now, but for future reference or anybody else installing one of these controllers. If your motor kicks or pulses, it's because of a timing issue or a connection issue. The timing comes from doing the self-learning. To check it, you connect the green wires, lift the wheel off the ground and switch on. The controller will do some figuring out for a few seconds trying different things, then the motor will turn slowly by itself, hopefully forwards. Once that happens, switch off and disconnect the green wires. If it goes backwards, repeat the procedure.

If that doesn't solve it, then you have either a connection issue somewhere or a faulty hall sensor in the motor.

Do the settings in the controller like I explained above and you'll be fine. AGS above is getting mixed up with P01 in KT controllers, so take no notice of that.

Zero start means normal throttle operation. non-zero means the throttle only operates when you're pedalling and have a working pedal sensor.

The P07 is only to get the speed to display correctly. If you set it wrong, you see the wrong speed in the LCD. All you need to do is spin the wheel by hand with the electrics switched on to see the speed on the LCD. You only need to get it in the correct range. The system counts pulses from the speed sensor in the motor. All Bafang motors with speed sensors have 1 or 6 magnets in them, so that's how many pulses you get per revolution, which is what that setting refers to. Normally, if you set it to zero, it will count pulses from the hall sensors instead, and automatically display the correct speed,, which is useful for when you have no speed sensor or the one you have packs up, but it can only get that when the motor is turning under power, not when free-wheeling. The only problem with that P07 setting is that if you set it so that the speed reads too high (1 when you have 6 magnets), the motor will cut because it thinks you're going over the maximum speed you set. It will think you're doing 60 mph when you're actually doing 10 mph.

 

[essex_chris]

Forgot all about this post. Ended up trimming retinning and resoldering all connections or ins some cases using connector blocks and got this all up and running a coupe of months back. 36v 250w motor runs great and both it and the controller stay nice and cool - the 36v 8ah battery is showing it's age and lack of capacity now as i haven't drained it yet but on a 5mie each way commute with the first mile of the outward journey a down a reasonable hill and therefore the last mile coming home uphill - i could leave the battery on the bike but each day at work i take it in and put it on charge. Should i want to divert from my usual route it gives me a bit more flexibility without worrying about riding a heavy dead ebike.

Have a couple of weeks off now so going to catchup on maintenance - used my last spare innertube and lost a couple of the spokes in the last fortnight. Finding myself doing a lot of window shopping of £1000-1200 bikes with 48v 15ah batteries and more power, lights, cargo brackets and baskets.

Only thing to note - have tried so many different settings on P07 but cannot get the speed to match GPS and the distance travelled to match either GPS or known route. Going to have another look at that as being able to glance and know reliably what the speed is would be a benefit. Controller maxes out at 20a - what woud be really interesting would be to wire in a power meter or arduino/pi zero and record this information - am a bit of a data geek so would find that fascinating to compare against incline and rider weight etc - this bike already gets a fair run in as a 20stone rider