SLCD-3 display settings, P and C parameters

What is the Maximum speed that can be set?

My current eBike the SSR Sandviper http://www.ssrmotorsports.com/store/ebicycle/sandviper.html
begins to cut the current to the motor when the speed approaches 20MPH and will reduce the current to zero as my speed exceeds 20MPH (pedaling very fast on flat ground). The local roads have a 25MPH speed limit so I would like my bike to travel up to 30MPH so that I can keep pace with traffic. I bike exclusively in urban areas without bike lanes and vehicles pass me very closely. The close proximity that the cars pass me is a safety concern. I would only be traveling this speed for a few hundred yards as I go over and under bridges where there is no alternative but to ride with cars.

I understand the limitations of traveling this speed such as gear ratios, wind resistance, excessive heat in the motor, excessive current flowing thru the wires, and so on so please keep the replies focused on how to achieve a speed over 20MPH, not reasons why I should not attempt such a thing.
 
IdleMind said:
The snow has almost all meted and I just rode my bike for the first time since last Oct. I would like to reset the odometer on the LCD display to zero to keep track of the miles for the year. Is there a way to do that. I couldn't find any info in the manual, perhaps restoring all the parameters to default setting would also reset the odometer, but then I'd have to re-enter the parameters.

The instrucitons for this are included in the manual here
https://bmsbattery.com/ebike-kit/670-s-lcd3-lcd-meter-for-s-series-controlers-ebike-kit.html

'5 seconds after the meter is powered on, at display 1, hold both the button (UP)
and the button (DOWN) simultaneously for about 2 seconds, the single trip time
(TM) and single trip distance (DST) flicker, then hold button shortly (SW), the
record contents of both will be cleared.'
 
Thanks for replying, but that's not exactly what I was looking for. I installed this system last summer and put about 1300 miles on it which shows up on one of the screens as total miles. I wanted to reset it to zero so I could track my total miles for just this year. It seems to be like a car odometer, you can reset the trip meter but can't tamper with the odometer.
 
thetimmy said:
What is the Maximum speed that can be set?

My current eBike the SSR Sandviper http://www.ssrmotorsports.com/store/ebicycle/sandviper.html
begins to cut the current to the motor when the speed approaches 20MPH and will reduce the current to zero as my speed exceeds 20MPH (pedaling very fast on flat ground). The local roads have a 25MPH speed limit so I would like my bike to travel up to 30MPH so that I can keep pace with traffic. I bike exclusively in urban areas without bike lanes and vehicles pass me very closely. The close proximity that the cars pass me is a safety concern. I would only be traveling this speed for a few hundred yards as I go over and under bridges where there is no alternative but to ride with cars.

I understand the limitations of traveling this speed such as gear ratios, wind resistance, excessive heat in the motor, excessive current flowing thru the wires, and so on so please keep the replies focused on how to achieve a speed over 20MPH, not reasons why I should not attempt such a thing.
It's not the LCD or controller that's limiting your current: It's the motor. As the motor speeds up, it generates a voltage called the back EMF that opposes (reduces) the voltage that's pushing the current through the motor. At 20 mph, the voltage generated is equal to your battery voltage, so no current can flow. To go faster, you need a different motor or a battery with more volts.
 
d8veh said:
It's not the LCD or controller that's limiting your current: It's the motor. As the motor speeds up, it generates a voltage called the back EMF that opposes (reduces) the voltage that's pushing the current through the motor. At 20 mph, the voltage generated is equal to your battery voltage, so no current can flow. To go faster, you need a different motor or a battery with more volts.

I'm fairly certain that there is a limit when I approach 32 km/h, so I performed the following test.
I start with a full battery and the PAS set to 1of5.
I begin pedaling and soon reached 15km/h.
I pull back the throttle and I can hear the motor whine and the current meter on my DMCH TC-480 LCD increases to 5of5 bars.
My speed increases to 33km/h and the current meter reads 2of5 bars, then 0of5 bars and the motor whine stops.
My speed increases to 37km/h and I stop pedaling but I have not let released the throttle.
My speed decreases to 31km/h and I hear the motor begin to whine and the current displays 5of5 bars.

Based on these tests and the legal requirements that eBikes do not exceed 20MPH (32km/h) I'm fairly certain that my motor isn't the limiting factor. It could be possible that my motor has a maximum RPM that just happens to equate to 20MPH when attached to a 26in wheel, but I believe that there is another factor at play here.
 
d8veh -

I did some additional research into back EMF and I believe that I understand your answer, please let me know if I'm correct.
http://electronics.stackexchange.com/questions/159512/back-emf-of-dc-motor
The following conditions are applied, the PAS is set to off, the throttle at maximum, and that the bike is traveling 10kmh to start.
When the throttle is engaged the difference between the input voltage (36v) and back-EMF (maybe 6v @ 10kmh) is 30V so the maximum amount of current is flowing.
The speed increases to 30kmh causing an increase in back-EMF, the difference between the input voltage (36v) and back-EMF (maybe 30V @ 30kmh) is 6V so the current flow is reduced (as shown by 2of5 bars on my current LCD).
The speed increases to 38kmh (downhill) causing an increase in back-EMF, the difference between the input voltage (36V) and back-EMF (maybe 38V @ 38kmh) is negative voltage thus the flow is now zero (as shown by my motor turning off when traveling down a steep hill).
The speed decreases to 30kmh causing a decrease in back-EMF, the difference between the input voltage (36v) and back-EMF (maybe 30V @ 30kmh) is now a positive 6v so a small current begins to flow (as shown by 1of5 bars on my current LCD and the motor turning on)

Based on this information, replacing the battery with a 48V model would allow for faster speeds, but I have a feeling it wouldn't be that simple.
 
The easiest way to check if your bike is restticted: Fully charge the battery, lift the wheel off the ground and spin up to maximum with the throttle. Check the maximum speed. Go out for a ride to use up at least half the battery charge. Repeat the above test. If the speed is the same, it's restricted.

Unrestricted, the speed is proportional to the battery voltage. A 36v battery is 42v fully charged and 31v when empty, so the speed will be 75% with a flat battery compared with fully charged.
 
Did somebody using a S-LCD3 or S-LCD5 possibly observe the new serial data protocol sent out by those newer displays providing the new "C-Parameters" ? Or does sb have info about that?

If sb wants to try: Most probably the protocol sent out by the S-LCD3/5 is also just a periodic repetition of a simple data string containing all settings, using 5VTTL, 9600/8-n-1 baud, simple XOR checksum - but should be somewhat longer than just 7 bytes.
One data log on the yellow wire vs black/GND, and possibly after a variation of settings like C12 (LVC level), C2, and C13, which interest me most would probably already clarify things.

(I don't have a S-LCD3/5 with new protocol so far. just want to change a few C-Settings in the controller, which understands the new prot.)
 
C13 adjust the level of regenerative braking from 0-5. C14 is for pedal assist power tuning 1-3 weak assist to strong assist.

Does anyone know how to wire the temp sensor in the motor to the display? I turned C8 to 1 which enables the motor temp reading. The display shows 32f on the screen so I just need to figure out the wiring. Green and yellow wires to the display are data lines. The blue wire is a data line that outputs to the controller. So you must have to wire the temp sensor to the controller.
 
The temperature sensor is inside the display, so you'd have to open it up to hack it for an external temperature sensor.
 
x-speed said:
I don't have a S-LCD3/5 with new protocol so far. just want to change a few C-Settings in the controller, which understands the new prot.
does someone know if you can change a C-parameter with a S-LCD3/5 and then use a S-LCD-2 and still have the parameter changed?

(I have a '3 on the shelf but uses a '2 but would like to change C12-parameter)
 
Does anyone know if the kt kcd3 screens sold for sondors geared motors have the C13 and C14 parameters wiped? Or are they just hidden perhaps?
I understand that they don't need regen on geared hubs but I bought one as a replacement for my broken lcd3 and the C parameters only seem to go upto C12?
Am I gonna need to order a whole new Lcd3 screen just for those 2 parameters, or is there something I can do with this one?
 
ABritinNY, I think it depends on the version you have. If you look at the KT-LCD3 V1 manual it only went up to C12. V2 and V3 manuals show C13 and C14. I have V3 and it has C13 and C14.
 
There's lots of different versions of the software in the controllers and LCDs with different parameters and settings. I think it's important to buy them as a matched pair.
 
Hi,

I've bought a S-LCD3 display with a S06SC controller.

But the problem is that I'm using a 42 magnets motor and a 26x reduction gearbox.

How to set P1 because the product of 42 and 26 is much higher that 255 which is the maximum value?!

Any idea anyone.

Have a Nice Day.

Thierry
 
More informations.

A guy has posted a review of the Q75 motor and said:
"I have the 201 rpm in a 700C wheel. It has surprisingly good torque for it's size, so is good for a roadbike conversion where assistance for hill-climbing is needed.
If you use a S06P controller, set P1 to 160 to get the correct syncronisation, otherwise, you lose sync and get a squealing noise with high power at low speed."

So it seems that the calculated value P1 = 13 x 16 = 208 doesn't give the best results.

Any ideas of possible response to my question just posted before.

Have A Nice Day.

Thierry
 
What is your total gear setup and math from magnets to road?

After all, the product of P1 (~ magnets * effective-gear) and wheelsize setting (~wheel-circumference) only tells/determines how many pole changes do we have per meter. This mainly enables speed calculation/display in the controller, and thus correct manifestation of a nominal speed limit.
Note, effective-gear should include (magnitude of) external gearing - e.g. for chain/middle motors.

Thus you can reduce P1 (<256) consistently when you increase the set wheelsize by the same factor for compensation.
Well, if "nominal" speed limit and display is not an issue, or when an external speed sensor in on, then you can even bypass consistency and set "anything" - what ever works.
However when the total pole change rate (pole changes per meters * max-speed) becomes very high, even the fast ("high speed sine controller") S06S may be too slow for you. Or it may fall back from sine to rect wave mode at some speed...
 
Thanks for your explanation x-speed.

That's the first time I understand the "reason why" of the P1 parameter!

And yes it's a homemade middle motor, U8 T Motor + 12:1 Neugart reducer + about 2:1 chain reducer to the Bottom Bracket, after I have 2 rings 44 & 32 and a 11-27 cassette to the 26" wheel. It's designed to have a good torque at 60-70rpm. But it's just to help me, definitely not a motorcycle!

I will have trials as soon as I receive the order and gives you the results.

Have A Nice Day.

Thierry
 
Hi guys.

I'm working on a trike that a local bike shop delivered for troubleshooting... it has a front wheel 20" DD motor, running 36v, thumb throttle, pedal sensor, and LCD3 display

Problem is this, when the display is powered up, the motor has massive coging, like if regen was enabled or parking brake feature or whatever.. as soon as i power off the display, the motor spins fine by hand.

Throttle will not activate, got the P settings set to zero start so it should but it does not.

disconnected the ebrakes, pedal sensor ( the sensor is mounted but the magnet ring is MIA .. ) i would like to disable the pedal sensor in the display settings, but seems like no option for it.

Used this pdf, will link here for ref.
http://wiki.memslist.com/pdfs/K-LCD3.pdf

anyone have any ideas ?
 
You need to set P1 to the right value = number of magnets in the motor x motor reduction ratio. If that doesn't work, try multiples of that number. If that doesn't work, try random numbers until you find something that works.
 
i wish it was that simple... :cry:

After much probing, a few observations...

1- with the display disconnected, Blue/Red and Black/Yellow bridged to run without the display, the motor behaves the same, severe magnetic lockup

2- with display hooked up, pressing the middle button a few times to flip displays, the Voltage shows as 26v ( from a 36v pack fully charged to 42v ) .. put a volt meter on the pins between the display and controller, confirmed 26v.... checking battery + and - at the controller from the battery pack shows 42v

whatever circuit the power is going thru, to the display via the controller, is giving a 10v drop somehow.

At this point, i'm pointing to a controller failure somehow.... but usually when a fet blows, you get coging even if the controller is not even powered up, in this case it only cogs while powered up.
 
Connecting yellow to black is wrong. It should be yellow to white (Tx to Rx, not Tx to ground).

Some of these KT sine wave controllers have regen, which might be why you have the cogging.
 
Hello, and thanks for this informative information.
One thing I was curious about, was the settings for 'real-time voltage monitoring' etc..
I was wondering how I can setup my display's battery meter, to show 0% at 40V, and be relative in between.
Because as of now, it just shows full up until my LVC kicks in (which has only been one time) and then I get the big battery flash icon and I'm cutoff and out of juice.

It would be nice not having to watch the voltage reading on the 3rd page,, and just stay on the first page of my display. Because when I'm watching the numbers of my battery voltage change I tend to get too anal and worried about my battery health etc. Thus having the battery meter liberate me of this.

Anyone know how to calibrate this battery meter?
Thanks

(I also have 2 battery packs installed, but I run them separately. So I'm going to play around with the presets options, I'll let you guys know how that all goes.)
 
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