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Pedal Sensors

Introduction

Pedal sensors form part of the PAS (Pedal Assist System) of eBikes. Pedal sensors read the pedal cadence speed and/or torque to determine when and how much motor assistance to provide.

Supported Pedal Sensors

There are 4 pedal sensor archetypes:

  • Single output dual hall sensors produce an output only in the forward direction.
  • Single output single hall sensors produce a different length pulse in one direction or the other.
  • Two output pedal sensors where the direction is encoded as a quadrature signal.
    • Usually, this type is used with pedal-torque sensors.
  • Pulse and direction sensors (not yet supported)

The following pedal cadence sensor types are supported:

  • Single Hall digital pedal cadence
  • Single output, dual Hall digital pedal cadence
  • Single Hall reverse digital pedal cadence
  • Quadrature speed (Sine/Cosine) digital pedal cadence
  • Quadrature torque with (Sine/Cosine) digital pedal cadence
  • Single Hall torque sensor (e.g.: Methode)
  • Single Hall reverse torque sensor (e.g.: LDS)

Wiring

Single output single or dual Hall pedal sensors typically have 3 wires: 5V or 12V, GND and signal. The signal wire must be wired to PFS/Digital input 2.

Two signal pedal speed sensors typically have 4 wires: 5V or 12V, GND, Sine signal and Cosine Signal. The Sine signal must be wired to PFS/Digital input 2 and the Cosine signal to Cruise/Digital input 1.

Configuration

Danger

Ensure vehicle is secured in case the motor engages unexpectedly while manually configuring your pedal sensor.

TIP

Make a backup copy of the parameter file often by saving it to file as shown before. It can be sent to ASI for support or you can revert if strange behaviour occurs.

Tip

Set Control command source to 0 / Serial stream to prevent the motor from accidentally spinning while manually setting the pedal sensor.

  1. Set Pedal sensor type as appropriate based on this table

    Pedal Sesnor type value Pedal Sensor type
    0 Single Hall
    1 Dual Hall
    3 Quadrature Torque
    4 Quadrature Speed
    5 Axle Torque
    6 Single Hall Reverse

  2. Enter your Pedal speed sensor pulses per revolution and press enter. a. Note: Quadrature pedal types Pedal speed sensor pulses per revolution is the sum of both sine and cosine pulses.

  3. Set Control command source to 2 / Pedal Sensor or 4 / throttle OR pedal sensor based on configuration,and press enter. This step will enable your pedal sensor.
  4. Ensure you do not have any faults, and test that when rotating the pedals in the forward direction, the motor spins up, and when no longer rotating or spinning the pedals backwards the motor coasts to a stop. If not see troubleshooting.
  5. Press Write to write the changes to the controller.
  6. In the Parameter drop-down menu, press Save to flash to save the parameters to the controller.
  7. Perform the Average pedal speed test to ensure the pedal sensor is set up correctly.

Average pedal speed test

To check if the pedal output is configured and is working properly. Operating the pedals in the forward direction and examining the value of the average pedal speed parameter. If the value is positive when pedalling forward and negative when pedalling backwards, the wiring is correct. If the average pedal speed values are reversed, then the wires connected to the PFS/Digital input 2 and Cruise/Digital input 1 inputs need to be reversed. If the average pedal speed value is erratic at a constant pedal cadence then there is likely an issue with the wiring.