New to e-bikes. Looking for help

[michaelgordon_1]

Hi all, I have been thinking about converting my Trek mountain bike for ages, I finally settled on a Bafang G020.500 DC rear wheel motor 48v-500w, the controller is KT-22A, the display is KT-LCD3, and the battery is a 48V- 15AH. The wheel size is 29" and the frame size 17.5. I completed the build which took me longer than I expected and I had to make a few tweeks to fit the frame, but finally got there and have the scars to prove it!! I am looking for help setting the display as I stupidly played around with the P settings and the C settings and now have no PAS. although the red led is flashing on the sensor and was working up until I played with the settings. I have trawled the web for the correct P and C settings but end up going round in circles. After watching many you tube videos I now understand how to set up the display, but the P settings and C settings for the Bafang motor and controller I cant find anywhere. Is there anyone with this set up or knowledge of the P and C settings that can help a first time builder in his hour of need?

 

[Nealh]

List your P & C's for us to see.

 

[Nealh]

P1 100.
P2 6.
P3 1.
P4 0 or 1.
P5 12.

C1 is for PAS so de[ends on the PAS used, we need to know which type.
C2 0 this shouldn't be changed.
C3 8.
C4 0.
C5 10.
C6 is display brightness so up to you.
C7 0.
C8 0.
C9 0.
C10 N.
C11 0.
C12 4.
C13 0.
C14 2 or 3.

 

[michaelgordon_1]

P1 100.
P2 6.
P3 1.
P4 0 or 1.
P5 12.

C1 is for PAS so de[ends on the PAS used, we need to know which type.
C2 0 this shouldn't be changed.
C3 8.
C4 0.
C5 10.
C6 is display brightness so up to you.
C7 0.
C8 0.
C9 0.
C10 N.
C11 0.
C12 4.
C13 0.
C14 2 or 3.

 

[michaelgordon_1]

Thank you so much. I will give these settings a go when i get back from my shift in work. I will post the result and let you know how i got on.

 

[Nealh]

C3 8 means what ever PAS level the bike is left at when switching off will be the same when one switches on again.
If one selects 0 - 5 then this will always be the default PAS level when switching on.
I use 0 or 8.

 

[Nealh]

Critically we need to know the PAS type sensor used as PAS will only work if C1 values are correctly set.

 

[michaelgordon_1]

Hi Nealh, Thanks again for your help, Regarding the pas sensor fitted to my bike, the part code is KT-D12L which I ordered as part of the kit, I suspect it is actually a KT-D12R which works on the chain ring side of the crank, I discovered this after first fitting to the opposite side, only to find the sensor would only flash when I pedalled backwards. I must admit this had me baffled for a while, after modifying the chain ring and removing the smallest, replacing it with the sensor disc all working ok, and the pick up and disc seem better protected from damage. I did not realise that these sensors were handed. I have looked at the P settings on my display and compared with your suggestions, three settings differed on my display P1-80..P2-1.. and P5-15.. against your P1-100..P2-6.. and P5-13, so i will change those, also all the C settings apart from C1 which is -2 on my display are the same as your suggestions. If you can help with the C1 setting, I will enter into the display and fingers crossed all will be well. I will post back once I have tried.

 

[Nealh]

The PAS working backwards LHS is an easy fix for there for also on the RHS, one simply flips the magnet disc face. Magnets a have a N or S pole, so if the sensor reads the wrong pole it ill work backwards.

The P1 relates to motor speed syncing 100 should be correct as it is internal ratio 1:5 x motor winding magnets 20, this setting should give an accurate 15.5mph cut off which can be verified by gps.
P2 should be 6 as your hub has 6 speed magnets.
P5 is the battery gauge voltage damping 12 - 15 will roughly show the battery status but it is best ignored and one should use the voltage readout for accuracy as a fuel gauge, 41v is the lowest one really wants to go and is a final limp home voltage with in a few miles of home. Generally 54.6v to 44v is the main range and near 44v one should be on the way back home.

 

[overlander]

The PAS working backwards LHS is an easy fix for there for also on the RHS, one simply flips the magnet disc face. Magnets a have a N or S pole, so if the sensor reads the wrong pole it ill work backwards.

The P1 relates to motor speed syncing 100 should be correct as it is internal ratio 1:5 x motor winding magnets 20, this setting should give an accurate 15.5mph cut off which cab be verified by gps.
P2 should be 6 as your hub has 6 speed magnets.
P5 is the battery gauge voltage damping 12 - 15 will roughly show the battery status but it is best ignored and one should use the voltage readout for accuracy as a fuel gauge, 41v is the lowest one really wants to go and is a final limp home voltage with in a few miles of home. Generally 54.6v to 44v is the main range and near 44v one should be on the way back home.

You certainly are very knowledgeable nealh, an asset to the forum

 

[michaelgordon_1]

Hi, so its just the C1 value I need to set the PAS correctly and then a trial ride to test all is good. I also agree with the above post by Overlander, I appreciate the fact that you will share your knowledge with fellow members.

 

[Nealh]

Yes C1 is dependant on PAS used, the V12L type on LHS is double hall and the value will be 5, 6 or 7 also maybe the 12 pole double hall sensor, all other two part sensors with 5 - 10 poles are 1, 2 or 3 .
C14 can also help if the pick up is a bit poor 1 ,2 or 3 are PAS signal strength weak, medium or high. One suspects it is more down to with gap between the two if a bit more then 1mm use value 3.

 

[Nealh]

If you verify P1 with gps and it is out (to fast) go down the scale one or two values at a time, 84 will be the min to go. Or if the reading is low, up the value.

 

[michaelgordon_1]

Thank you, I will post the results over the weekend.

 

[michaelgordon_1]

Hi all, just a update on how I got on after entering the values suggested by Nealh today. I am pleased to say that all is good, I have PAS working. throttle working, and the bike rides well. I am going to check the P1 values against GPS and make a adjustment if needed, but just glad to have the bike up and running for now. Thanks again to Nealh for his help on this, and I look forward to enjoying my new e-bike with a few rides out in my local area ( north wales coast ).

 

[Nealh]

Hi all, just a update on how I got on after entering the values suggested by Nealh today. I am pleased to say that all is good, I have PAS working. throttle working, and the bike rides well. I am going to check the P1 values against GPS and make a adjustment if needed, but just glad to have the bike up and running for now. Thanks again to Nealh for his help on this, and I look forward to enjoying my new e-bike with a few rides out in my local area ( north wales coast ).

Another happy customer we I have helped out .
I also had to like the post as my name was mentioned , now my hat doesn't fit.