Skip to content

Usage and configuration of firmware version 0.17.x

Leon edited this page Jan 10, 2019 · 27 revisions

The following applies to firmware version 0.17.x only!

CAUTION: always use the same firmware version for both the motor controller and LCD unless otherwise specified!

NOTE: Before using the mid drive with new firmware, you must configure the options on the display correctly. For instance, you should configure your battery low voltage cut off so as to not over discharge the battery. Do set all other parameters also.

Table of Contents

KT-LCD3 information and configurations

1. Main screen

  • Main screen
    • Assist level: assist level sets the motor power as a factor of the power that rider is doing on the pedals. For instance, if current assist level is 3 and if this level is configured as a factor of 2.0, when rider is doing on the pedals a power of 100 watts, the motor power used will then be 200 watts.
      The assist level is changed by pressing UP and DOWN buttons.
    • Ebike wheel speed: the value of wheel speed in kms or mph.
    • Motor power: power used by the motor (in watts) that is being draw from the battery.
    • Battery state of charge: Battery state of charge based on battery voltage. There are 6 different levels. When battery is near empty, the battery symbol will be empty and blinking and the motor power will be reduced up to battery being totally empty.
      The battery voltage used to calculate the state of charge has in consideration the battery pack resistance to avoid floating when power is being draw from the battery (the battery pack resistance value is set on configurations menu).
    • Lights: enabled/disable with a long press of UP button (LCD back light will also be change, depending on the configurations) and the motor controller will enable/disable the ebike lights.
    • Brake: Brake symbol is enabled when user press the ebike brakes (good to check that sensor brakes are working).
    • Time Measurement: Time measurement functions. Switch between TM or TTM to get measured time either from trip or user last reset.
    • Walk assist: enabled/disable with a long press of DOWN button. Although it is implemented on LCD, it is not yet implemented on the motor controller.
    • Offroad mode: if you have enabled the offroad mode (see configuration section below) this can be activated with the ON/OFF and UP button combination and deactivated with the ON/OFF and DOWN button combination. When active, the assist symbol above the assist level will start blinking. Offroad mode is disabled and inactive by default. We do not recommend you to activate offroad mode on public roads. In many countries offroad mode may only be used on private property.
    • Motor temperature / battery state of charge in percentage: this field can show either the motor temperature (when the sensor is installed), the battery state in percentage or none (you can switch what is shown by pressing POWER and UP buttons simultaneously).
      • Motor temperature: motor temperature in degrees Celsius. When the power power is being limited due to over temperature, this field will blink (configure the temperature limits on configurations menu).
      • Battery state of charge in percentage: this percentage value is based on the accumulated battery power draw from your battery pack (set options on configurations menu).
    • Odometer field: this field can show a few variables that are logic grouped in sub fields. You can change between fields by pressing ON/OFF button and sub fields by quick pressing UP button followed a long press UP button (you will see temporary the field and sub field number blinking on wheel speed field).
      • 1. Distance
        • 1.0 Trip distance: can be reset by quickly pressing DOWN button followed by a long press DOWN button (you will see trip distance value blinking if you keep pressed DOWN button and after 3 seconds the value will reset).
        • 1.1 Distance since power on this value is automatically reset at power on. You can also reset by quick pressing DOWN button followed a long press DOWN button (you will see trip distance value blinking if you keep pressed DOWN button and after 3 seconds the value will reset).
        • 1.2 Odometer: can be set to a specific value on the configurations menu.
      • 2. Battery State of Charge (not shown if function is disabled in configuration menu)
        • 2.0 State of charge in percentage
        • 2.1 Consumed watt-hours
      • 3. Battery State
        • 3.0 Voltage: Voltage of battery.
        • 3.1 Current:: instantaneous current drawn from battery.
      • 4. Pedals
        • 4.0 Rider pedal power: in watts.
        • 4.1 Pedal cadence: in revolutions per minute.
        • 4.2 Pedal torque: in newton meter.
      • 5. Motor Temperature (not shown if function is disabled in configuration menu)
        • 5.0 Motor temperature: Temperature of motor.
      • 6. Time Measurement
        • 6.0 Time Measurement: Time measured since display is powered on.
        • 6.1 Total Time Measurement: Total time measured since last reset.

2. Motor maximum power screen

In the maximum motor power sub menu you can set a limit to maximum motor power. This can be useful for various reasons, like controlling the battery range for long travels.

Access this screen by long pressing ON/OFF and UP buttons. Press UP and DOWN buttons to increase/decrease the value. Exit this screen by long pressing the ON/OFF button.

How it works: the motor controller will automatically limit current and therefore limit maximum motor power. As the battery discharges and the voltage decreases the motor controller will adapt and adjust the current to maintain the set limit.

NOTES:

  • This function cannot be used when offroad mode is enabled. Disable offroad mode first.
  • It is not possible to set a higher motor power than the maximum allowed battery current set by user.

Configuration menu

  • To enter configuration menu: long press UP and DOWN buttons.
  • To enter sub menus: press UP or DOWN button
  • To move to next subscreen: press ON/OFF button
  • To exit: long press the ON/OFF button

0: General Setup

Submenu number Configuration name Default value Description
0 Unit Metric Set (0) for metric units (km/h and kilometers) or (1) for imperial units (mph and miles)
1 Maximum wheel speed 50 Enter your speed limit (by law) to run legal on public roads. The motor will fade out from -0.5 km/h to +2,0 km/h. Tip: Europe has generally a speed limit of 25 km/h for E-Bikes.
2 Wheel circumference 2050 Enter your wheel circumference so that speed and distance is correctly calculated.

Tip: Search on Google how to measure wheel circumference. But for a quick setup with ball park values use: 26 wheel = 2050; 27 wheel = 2150; 27.5 wheel =2215; 28 wheel = 2250; 29 wheel = 2300

1: Battery

Submenu number Configuration name Default value Description
0 Maximum current from battery 16 ampere Set maximum allowable current to be pulled from the battery. This value is limited internally by the firmware to the safe value of 18 ampere.
1 Battery low-cut-off voltage 39 volt The controller will reduce power to stay over this limit! Calculate the limit by multiplying amount of cells in series with the safe cut-off-voltage per cell, which is usually between 2.8 - 3.0 volts. Example: 39.0 volts for: 13 cells in series * 3.0 volts = 39.0 volts.

Tip: The standard Samsung cells allow down to 2.75 V but you need some safety margin because not all cells have exactly the same capacity. But setting a too large value you loose range and power. I like to use the value of 29 V for a 36 V battery pack (= 10 cells in series).
2 Number of cells in series 13 Set this value so the battery state indicator works properly. This value can be any integer from 7 to 14

Example values: 7 for 24 V battery; 10 for 36 V battery; 13 for 48 V battery; 14 for 52 V battery.
3 Battery internal resistance 130 milliohms Set this value so the battery state indicator does not display a lower state of charge when pulling a lot of power from battery and the voltage sags.

Explanation: If you set the value to 0, you will see the battery state indicator fluctuating whenever the motor draws current from the battery. This is due to the internal resistance in the battery. The fluctuation will disappear and be filtered out with a correct value.

How to calculate the battery pack resistance:
1. Limit the battery current to a known value, e.g. 10 amps
2. Read the voltage drop when motor is pulling the 10 amps
3. Calculate the resistance value

Example for 10 amps current, R = U / I, R = 1.2 volts drop / 10 amps, R = 0.120 = 120 milliohms.
4 Battery voltage (SOC) - Measured and continuously updated battery voltage State Of Charge (SOC). This value is filtered using the battery pack resistance.

Tip: Here you can evaluate and test how the set internal resistance of the battery affects the voltage reading.

2: Battery Capacity Setup

Under this configuration menu you can set parameters to display the state of charge of your E-Bike battery. If this function is enabled it will display how many watt-hours have been consumed since last charge and what percentage remains of the battery. Depending on preferences it is possible to set so that percentage of consumed charge is displayed instead of percentage of remaining charge.

Tip: If this function is enabled you will be able to see percentage of charge in the temperature field on your display. To enable or disable just click the ON/OFF-button together with the DOWN-button at the same time. Do not forget to enable and set up the function below.

Submenu number Configuration name Default value Description
0 Enable and set State of Charge function 0 Set (1) to enable function. It will display watt-hours consumed and percentage of charge remaining, i.e., display percentage value from 100 % to 0 %.

Set (2) to enable function. It will display watt-hours consumed and percentage of charge consumed, i.e., display percentage value from 0 % to 100 %.

Set (0) to disable the function.
1 Threshold voltage to reset watt-hour meter 54.2 volt When powering on the display this value is compared to the battery voltage. If it is lower, the battery is expected to be fully charged and the watt-hour meter is reset.

Tip: To find a suitable value, fully charge the battery and measure the voltage on the KT-LCD3, use a slightly lower value for the threshold voltage.

Example: my 48 V battery charges up to 54.6 volts, so I set the threshold to 54.2 volts.
2 Total watt-hours of battery 0 Set the total capacity in watt-hours your battery has.

Tip: fully charge the battery and then discharge it completely and use the measured value to input here.

Tip: the capacities stated from suppliers are often too high, expect a value of around 80 % - 90 % of stated value. I use 350 Wh for my 386 Wh battery.

Tip: roughly calculate the capacity by multiplying the nominal voltage with the nominal ampere hours. Example: a 48 volt, 14.5 Ah battery has a nominal watt-hour capacity of 696 Wh.
3 Consumed watt-hours - This value represents consumed watt-hours since last reset. It is reset automatically when you power on the LCD and the battery is fully charged, i.e., above the set threshold voltage.

3: Assist Levels

Here you can configure how many assist levels you wish to be able to select and also their respective multipliers. The defaults should already work for most people.

The assist level sets the motor power as a factor of the power the rider is generating on the crankshaft. For instance, if assist level 3 is chosen and configured with a multiplier of 2.0, when the rider is generating a power of 100 watts, the motor power will assist another 200 watts.

Submenu number Configuration name Default value Description
0 Number of assist levels 5 Select the desired number of assist levels from a minimum of 1 to a maximum of 9.
1 Assist level 1 multiplier 0.5 The value with which the human pedaling power is multiplied with.

Example: 0.5 * 200 W (human power) = 100 W assist power. This results in 300 W total power.
2 Assist level X multiplier .... The desired multiplier for assist level X.

4: Startup BOOST function

Here you can enable, disable and configure the BOOST feature. This feature helps from standstills where you might need greater assistance. It gives more power during a set time and then fades the power back to normal assistance. To configure the function for you likening please set appropriate values.

Submenu number Configuration name Default value Description
0 BOOST feature 0 Set (1) to enable or (0) to disable.
1 On startup only / everytime 1 Set (1) to enable BOOST feature every time pedal cadence or torque sensor value are zero. Set (0) to enable BOOST feature only when startup and bicycle wheel speed is equal to zero;
2 Limit BOOST power to max battery power 0 Set (1) to enable BOOST power limit to the maximum battery power value. Set (0) to disable.
3 BOOST time 2.0 seconds Set time limit of BOOST.
4 Fade out BOOST 3.5 seconds Set time limit to transition of power from BOOST to regular power.
5 Assist level 1 BOOST multiplier 4 Set the BOOST multipler corresponding to assist level 1.

Tip: See assist levels for more information about multipliers.
6 Assist level X BOOST multiplier - Set the BOOST multipler corresponding to assist level X.

Tip: See assist levels for more information about multipliers.

5: Motor Temperature Protection

This function protects your motor from overheating resulting in permanent damage/loss of torque. See: TSDZ2 motor demagnetized due to overheating. You can only use and enable this feature if you have installed the motor temperature sensor.

How it works

If you have installed the motor temperature sensor and you enable the function, you will be able to see the motor temperature in the temperature field of the display. When the set minimum motor temperature threshold is reached, the motor current will start to be limited. If the temperature keeps rising this will result in even more current, and therefore overall power, limitations. If the maximum motor temperature is reached the current will be completely limited.

The temperature value on the display will blink if the motor current is being limited. As the function limits the current more it will blink faster corresponding to higher limitations on current. Finally, if the current is completely limited, the blink rate will be very fast.

Submenu number Configuration name Default value Description
0 Motor temperature protection 0 Set (1) to enable the motor temperature control or set (0) to disable.

NOTE: if you do not have the motor temperature sensor installed, you should disable this option and ignore the immediate configurations below.
1 Minimum temperature 75 °C Set the minimum motor temperature at which the motor current will start to be limited.
2 Maximum temperature 85 °C Set the maximum motor temperature at which the motor current will be completely blocked, i.e., motor shutoff.

6: Display

Submenu number Configuration name Default value Description
0 LCD brightness when backlight is off 5 Percentage of brightness when backlight is turned off, e.g., 5 %
1 LCD brightness when backlight is on 80 Percentage of brightness when backlight is turned on, e.g., 80 %
2 LCD auto power off 15 Automatic power off after set amount of minutes.
3 Reset to factory defaults 0
  1. Increase the value to 10
  2. The display will turn off
  3. Turn it on again
  4. Factory default settings will be restored

7: Offroad Mode

This function enables user to limit speed and power when using bike on road. When using the bike off road where laws may be different it is possible to toggle Offroad mode and unlock a higher speed or power limit. Set parameters suitable for your specific laws and preferences.

Submenu number Configuration name Default value Description
0 Feature toggle 0 Select (1) to enable or (0) to disable.
1 Active on system startup 0 Determines whether offroad mode should be active on system startup. Select (1) to enable or select (0) to disable.
2 Speed limit 25 km/h This speed limit is used when offroad mode is not active. Configure your speed which is legal for using on public roads. The motor will fade out power from -0.5 km/h to +2,0 km/h.
3 Limit power 0 Determines whether power should be limited when offroad mode is not active. Select (1) to enable or (0) to disable.
4 Power limit 250 W The power limit in watts. For most countries in Europe the legal power limit is 250 W.

8: Various

Submenu number Configuration name Default value Description
0 Motor voltage type 0 Depending on type of motor, select appropriate value so that FOC calculations are correctly executed. The voltage of the battery does not matter, this value should always be set depending on type of motor.

  • Set 0 for 48 V brushless motor (TSDZ2 52 V version has a 48 V brushless motor).
  • Set 1 for 36 V brushless motor.
  • Set 2 (EXPERIMENTAL) for the 36 V brushless motor, high cadence mode. Maybe not good for the motor, use at your own risk. Probably only suitable for the 36 V motor.
1 Motor assistance startup without pedal rotation 0 Select (1) to enable or select (0) to disable. Recommended to keep at disabled (0) if you do not have brake sensors installed.
2 Set odometer 0 Set the odometer to preferred value. Increase the value by pressing UP button or press and hold to have the value increment automatically. Decrease the value by pressing the DOWN button or press and hold to have the value decrement automatically.

9: Advanced Technical Data

Submenu number Configuration name Description
0 ADC throttle See the current value
1 Throttle See the current value
2 ADC pedal torque sensor See the current value
3 Pedal torque sensor See the current value
4 Pedal cadence See the current value
5 Pedal human power See the current value
6 PWM duty cycle See the current value
7 Motor speed in ERPs See the current value
8 FOC angle See the current value. This value must be multiplied by 1.4 to get angle value in degrees.
Clone this wiki locally