Bafang G310 with £17 ebay KT controller and KT LCD3 - problems

[DylanWinter]

I am looking for some help with some weitrd symptoms on a bike conversion. I bought a Bafang G310 front geared hub 250 watts from Aliexpress (£90 plus £40 to get it into the UK}. I bought a £17 controller (linked below), throttle,KT LCD3 (linked below),


I have fitted the bafang into the front wheel of my Raleigh Chiltern and put the controller and batteries in the front basket - currently connected to 36 volt 13 amp ebike battery. Eventually I aim to use 2 x 18 volt 12 amp drill batteries that will fit in the basket

I have been attempting to get the controller to talk to the Bafang -

settings are

P1 - 88 or 176 tried both
P2 0 or 6 tried both
P3 1 or 0 tried both
P4 0
P5 15
C1 05
C2 0
C3 1
C4 4
C510
C6 1
C7 0
C8 is unidentified
C9 0
C10 No
C11 0
C12 4
C13 0
C14 3
C15 4

The controller shows a thr logo when I engage the throttle, walk assist shows the little man walking but the wheel does not turn

- unless I spin the wheel backwards - then the motor gives a tiny kick -

If I have the throttle engaged and apply gentle backwards pressure to the wheel then the motor judders and resists the push

If I hand spin the wheel forwards then I get a speed reading via the sensors in the Bafang. I have also turned that off to see if that makes any difference

I have made four other ebikes but all with mid drives. For this one I just wanted to add an inconspicious motor and hide everything in the tasteful front basket. I am not planning to use any motor cut off brakes as I want to keep the bike as clear of wires as I can.

I have no cadence ring and tried with cut-out brakes but the symptoms are the same

I have spent five days on this chasing around the web and looking at lots of threads on here

can anyone here help me

or...have I bought the wrong controller?

 

[datek]

I don't really have good pointers, but I guess you could try different C2 (motor phase classification, 0-7) options if it does anything. On my cheapie no-name motor 2 of the options runs the motor fine, others make it twitch/growl.

 

[DylanWinter]

I don't really have good pointers, but I guess you could try different C2 (motor phase classification, 0-7) options if it does anything. On my cheapie no-name motor 2 of the options runs the motor fine, others make it twitch/growl.

thank you for suggesting that

I tried to ring the changes on those settings this evening in the shed and the motor behaves the same way as if it is set on zero. If I spin it in reverse and hit the throttle it stops suddenly. If I put back ressure on the wheel gently shoving it backwards then it judders - but only with the throttle engaged.

I do not have a PAS connected - and all the posts I have seen say that by having it disconnected I am disabling it. In some setttings I can get a forward speed recorded when turning the wheel by hand - or I can disable that so the controller is speaking to the Bafang.


I must say fitting the BBS01s was quite a bit easier.

I have seen posts where the PAS is put on the wrong side of the bike in which case it is running backwards - you can change the software in some way to make it read the opposite .

I am only doing this because I really like riding the Raleigh chiltern, I like the sturmey archer gears along with a back pedal brake. I quite like the sensation of being pulled up hills and the G310/11 is silent - which sounds nice

Dylan

 

[docw009]

When I don't know if I have the throttle wired or configured properly on a KT controller, I do walk mode to see if the motor runs. That is the down button on the LCD3 control. Hold it down for a few seconds. Wheel is suppossed to spin at 6km/hr. If it doesn't, there's a motor-connecctor issue.

I've connected three different Bafang motors, the SWXH, BPM, and a fat tire G060 to KT controllers with 9 pin connectors direct from the controller, so I am sure KT and Bafang agree on the pinout. That would suggest a bad controller. Kind of rare, but I've had one new out of the box not work right, although it still spun the motor,

I know you have no PAS. but, from your mid drive installs, you do know that PAS has to be set at 1 or higher to enable throttle. If you want to ignore PAS levels, I believe that you can set C4 =4 and P4 =1 to have throttle always on.

 

[DylanWinter]

When I don't know if I have the throttle wired or configured properly on a KT controller, I do walk mode to see if the motor runs. That is the down button on the LCD3 control. Hold it down for a few seconds. Wheel is suppossed to spin at 6km/hr. If it doesn't, there's a motor-connecctor issue.

I've connected three different Bafang motors, the SWXH, BPM, and a fat tire G060 to KT controllers with 9 pin connectors direct from the controller, so I am sure KT and Bafang agree on the pinout. That would suggest a bad controller. Kind of rare, but I've had one new out of the box not work right, although it still spun the motor,

I know you have no PAS. but, from your mid drive installs, you do know that PAS has to be set at 1 or higher to enable throttle. If you want to ignore PAS levels, I believe that you can set C4 =4 and P4 =1 to have throttle always on.

thanks for this

I will have a crack at it in the morning. The walk assist does not work with the motor - although the little man pushing a bike comes up on the controller. My neighbour has a controller somewhere in his shed - so I will see if I can link that one up

the controller I bought with waterproof julet connections is rated at an average of 7 amps and peak at 15..... the Bafang is only 250 watts so the controller should have enough grunt to make the wheel turn. Fortunately I am retired and have time to arse about like this.

Dylan

 

[DylanWinter]

I am still failing on this

has anyone bought a duff controller?

is mine too small... too cheap?

 

[docw009]

Pull the motor connector off, power up the controller. and hit throttle to see if it gives you the Hall Sensor error, Just a test to see if the KT unit is doing its diagnostics.

 

[DylanWinter]

Pull the motor connector off, power up the controller. and hit throttle to see if it gives you the Hall Sensor error, Just a test to see if the KT unit is doing its diagnostics.

thanks for the suggestion

I just tried that and no error message came up

The throttle sign comes up though

I also assume the KT is getting signals from the Hall sensor as when I spin the wheel forwards I get a speed number showing. But I get no speed reading when spinning in reverse. So it seems to be reading the hall sensor in the correct direction. I did see on one website that one thing that should hapen as soon as you touch the throttle is that the stator should line istelf up in the right place ready to start. This would also account for the gentle juddering when I try to turn the wheel backwards.

For some reason the KT controller is not going through to the second art of the equation.

This would lead me to the throttle being the problem...... but..... the walk asist does not work either

Neighbour came over with a similar sized KT controller to mine - but it has entirely different Julet connections. I also tried his Bafng rear hub motor - it calls itself a BFY 1706 - needless to say I cannot find any trace of such a motor on the web..... I get no movemeent out of that but then the poles x gear ratio would be entirely different.

Aaaagh!



so I am at another dead end.....

maybe I shouod just buy a PAS ... connect that up and see if it runs - although all the literature suggests that you do not need a PAS sensor plugged in for throttle only

Dylan

 

[amberwolf]

If it doesn't work in walk mode, it's not going to work in any other mode; the extra inputs will just give you more things to troubleshoot.

If your motor is a geared motor (yours is AFAICT), then the controller cannot get speed readings from the *motor* halls when spinning just the wheel forward by hand, only backward, because of the clutch that prevents the wheel from turning the motor.

So the speed reading comes from a separate wheel speed sensor (often a white wire in the cable) that reads a magnet on the case, isntead of the motor.

This means that you don't yet have a confirmation that hte motor's hall signals are active or correctly wired.

Since you get a tiny kick spinning the wheel backwards, it means that the ocntroller does detect that hte motor is spinning at that point, and is either tryingg to stop it from spinning, or is trying to get it started but doesn't get the expected feedback.

The most likely problem (because this is very common) is the wrong phase/hall combination. I don't recall if the KT has a self-learn function, but if it does, try that. If not, then if you can access the hall signal wires while the motor is connected to the controlelr you can verify that they are actually providing signals on all three wires. If they are, then you can try manually swapping phase or hall wires until the motor spins, and if it's in the wrong directly either use the reverse function of the controller if it has one, or then swap the other wires not already swapped around until it spins the right direction. (note that there are some combinations that appear to work but take more current than it should and/or spin way faster than ti should.

 

[DylanWinter]

thank you for this

I will read , learn and inwardly digest this overnight at the lightening speed of a 68 year old bloke

I wonder if the cheap controller does not self learn in which case maybe I should buy a better controller

at the moment the whole thing is linked up with waterproof(ish) julet connectors

not keen on dismantling them

am prepared to spend on a better controller and display

any suggestions?



Dylan

 

[amberwolf]

If you need more info, just ask and my 55 year old brain and fingers will do their best (not necessarily at the same time).

 

[AGS]

I think your C4 setting may be an issue and I think it should be set to 0 so the throttle works immediately and provides full power all of the time, given you have no pas to start the motor.

P3 should also be set to 1 to provide full throttle all of the time, irrespective of what pas is asking it to do.

Although walk mode should work regardless of these settings, so something else is arwy.

 

[richj8990]

I am looking for some help with some weitrd symptoms on a bike conversion. I bought a Bafang G310 front geared hub 250 watts from Aliexpress (£90 plus £40 to get it into the UK}. I bought a £17 controller (linked below), throttle,KT LCD3 (linked below),


I have fitted the bafang into the front wheel of my Raleigh Chiltern and put the controller and batteries in the front basket - currently connected to 36 volt 13 amp ebike battery. Eventually I aim to use 2 x 18 volt 12 amp drill batteries that will fit in the basket

I have been attempting to get the controller to talk to the Bafang -

settings are

P1 - 88 or 176 tried both
P2 0 or 6 tried both
P3 1 or 0 tried both
P4 0
P5 15
C1 05
C2 0
C3 1
C4 4
C510
C6 1
C7 0
C8 is unidentified
C9 0
C10 No
C11 0
C12 4
C13 0
C14 3
C15 4

The controller shows a thr logo when I engage the throttle, walk assist shows the little man walking but the wheel does not turn

- unless I spin the wheel backwards - then the motor gives a tiny kick -

If I have the throttle engaged and apply gentle backwards pressure to the wheel then the motor judders and resists the push

If I hand spin the wheel forwards then I get a speed reading via the sensors in the Bafang. I have also turned that off to see if that makes any difference

I have made four other ebikes but all with mid drives. For this one I just wanted to add an inconspicious motor and hide everything in the tasteful front basket. I am not planning to use any motor cut off brakes as I want to keep the bike as clear of wires as I can.

I have no cadence ring and tried with cut-out brakes but the symptoms are the same

I have spent five days on this chasing around the web and looking at lots of threads on here

can anyone here help me

or...have I bought the wrong controller?

View attachment 338716View attachment 338717View attachment 338722View attachment 338724

Are you sure C1 is at 5. The manual says it can only do 0-3.

C4 can be 0 or 4, either way 'should' work. 0 probably better for now.

Otherwise the parameters look fine. Motor shudder is very common when things are not working. It could be the battery connection; it also could be that the P1 speed sensor is screwed up and the controller thinks the bike is going too fast even when it's not going anywhere, so it's not allowing any power. Lower P1 down to say 70, see what happens. Rotate the wheel forward by hand and see if the speed starts going crazy and reads like 45 mph or 70 kph on the display. Or does it read a realistic mph like 3 or 4. I just had a similar issue this morning (motor worked but kept cutting out) because I set P1 to 1. Reset it at 90-120 and it's more or less OK now, so you may need to lower P1 below that range in your particular case.

Are you also sure that the 6-pin white hall sensor is plugged in fine and the three phase wires (should be green, blue, yellow) are firmly 'clicked' in.

The other thing is that the throttle may simply not get along with the controller. Keep working on it, try getting another throttle first and then controller if needed.

 

[DylanWinter]

Week 2 of this insane journey... I am retired so I have time but I would like to get this bike going

I have tried all the suggesions above ..... but still no luck



so the Bafang came with this lead - which I am not using




My power connection is far from perfect but it works on the BBso1s I have been using so I am confident that I am getting enugh power through these connections

I am also using the Julet connectiions for the motor and throttle

I have no brake levers attached - although I did try that using the levers from another home built ebike

I have no PAS attached

all the reading I have done says that this should not matter







Buying a PAS £10 is the next move unless I hit paydirt today

 

[DylanWinter]

video of symptoms

I have ordered a PAS - fingers crossed

D

 

[AGS]

Don’t rule out the possibility that you may have bent a pin when snapping the Juliets together.

 

[DylanWinter]

thanks for the idea

checked the pins - they look fine

I will await the arrival of the PAS and have another crack at it.

D

PS - wish I had bought a kit now as I did with the BBCSOs I have already fitted but i was lusting after the silent running and small format

 

[docw009]

IT's got to be either a bad motor or a dead controller.

thanks for the suggestion

I just tried that and no error message came up

The throttle sign comes up though

Let's confirm this. WIth the motor not attached, cable dangling, you can work the throttle and not see the ERR 03 message? Should also thorw an error in Walk mode.

That's unlike every KT controller I've installed, Would point to a controller that can't read the Hall sensors. Probably broken,

 

[DylanWinter]

No error pops up

is that definitive of a fekked controller then

maybe you are correct

D

 

[E-HP]

amberwolf gave you the most likely problem solution in post #9. You stated "I have tried all the suggestions above ..... but still no luck", so what steps did you take to correct the hall and phase wiring combinations?

This chart helps to avoid going through all 36 combinations, since it's easy to lose track when going the manual route.

Testing BLDC motor's Phase Wiring - Hall Sensors and Wiring. - Electricbike.com Ebike Forum

Testing electrical components of a typical hub motor with a digital multi meter. First take a few minuets and look over the wiring going into the motor for cuts, scrapes, missing insulation and other wiring issues or poor connections that should be resolved first. Smell for evidence of...

electricbike.com

 

[DylanWinter]

No error pops up

is that definitive of a fekked controller then

maybe you are correct

D

hold on

getting error 03

I was not pushing the throttle correctly

so that now suggests the hall sensor is not working or that I am not getting a signal right somewhere

Dylan

 

[DylanWinter]

amberwolf gave you the most likely problem solution in post #9. You stated "I have tried all the suggestions above ..... but still no luck", so what steps did you take to correct the hall and phase wiring combinations?

This chart helps to avoid going through all 36 combinations, since it's easy to lose track when going the manual route.

Testing BLDC motor's Phase Wiring - Hall Sensors and Wiring. - Electricbike.com Ebike Forum

Testing electrical components of a typical hub motor with a digital multi meter. First take a few minuets and look over the wiring going into the motor for cuts, scrapes, missing insulation and other wiring issues or poor connections that should be resolved first. Smell for evidence of...

electricbike.com

I guess this means it is time to start cutting wires as there is no software fix for it - is that right?

or can I buy a better controller that self learns but still uses waterproof Julet plugs

I live in a wet place and would like to kee things as weather-proof as I can

 

[AGS]

You can cut the wires in the middle of the cable and solder them when you have found the correct phase combination and use heat shrink sleeving for protection and waterproofing. Then it will be nearly as good as new.

 

[richj8990]

A different opinion would be: time is money, and maybe if he's busy he just buys a better controller. I know some people love tinkering but in this case maybe you just throw in the towel and buy a better controller.

 

[DylanWinter]

A different opinion would be: time is money, and maybe if he's busy he just buys a better controller. I know some people love tinkering but in this case maybe you just throw in the towel and buy a better controller.

I think that would be my best option

but what controller?