Pedal Sensors

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

Supported Pedal Sensor Types

Type Value	Sensor Type	Direction	Notes
0	Single Hall	Duty cycle directional	Greater than 50% duty cycle is forward
1	Single Hall	Non-directional	No direction detection
3	Quadrature Speed & Torque	PFS leads Cruise	Duty cycle 50:50
4	Quadrature Speed only	PFS leads Cruise	Duty cycle 50:50
5	Axle Torque	Non-directional	Simple torque only (legacy)
6	Single Hall Inverted	Duty cycle directional	Less than 50% duty cycle is forward
7	Single Hall and Torque	Logical input directional	Cruise input active is forward
8	Single Hall and Torque	Non-directional	Combined cadence + torque
9	Dyname Torque	Non-directional	Refined torque only

Wiring

Single-Output Pedal Cadence Sensor

Single output sensors typically have 3 wires:

Wire	Connection
Power	5V or 12V supply
GND	Ground
Signal	PFS/Digital input 2

Single-Output with Direction

Sensors with direction detection have 4 wires:

Wire	Connection
Power	5V or 12V supply
GND	Ground
Signal	PFS/Digital input 2
Direction	Cruise/Digital input 1

Two-Output Quadrature Sensor

Quadrature speed sensors have 4 wires:

Wire	Connection
Power	5V or 12V supply
GND	Ground
Sine Signal	PFS/Digital input 2
Cosine Signal	Cruise/Digital input 1

Axle Torque Legacy

The Axle torque (Type 5) is a legacy configuration that only supports the Throttle analog input as a source. All other pedal torque sensor inputs can use any available analog input (Throttle, Brake1, Brake2, ABMS, or remote throttle voltage).

Configuration

Safety Warning

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

Configuration Tips

Make backup copies of your parameter file often
Set Control command source to 0 / Serial stream to prevent motor from spinning while configuring

Cadence-Only Sensors (Types 0, 1, 4, 6)

Set Sensor Type

Set Pedal sensor type to the appropriate value (0, 1, 4, or 6).

Set Pulses Per Revolution

Enter your Pedal speed sensor pulses per revolution.

Note for Quadrature types:

Firmware 6.026 and earlier: Sum of both PFS/sine and Cruise/cosine pulses
Firmware 6.027+: Sum of PFS/Sine pulses only

Set Control Source

Set Control command source to:

2 / Pedal Sensor for pedal-only control
4 / Throttle OR Pedal Sensor for combined control

Test Operation

Verify:

No faults present
Pedaling forward spins the motor
Stopping pedals or pedaling backwards causes motor to coast

Verify with Average Pedal Speed Test

See the Average Pedal Speed Test section below.

Cadence with Torque Sensors (Types 3, 7, 8)

Set Sensor Type

Set Pedal sensor type to the appropriate value (3, 7, or 8).

Set Pulses Per Revolution

Enter your Pedal speed sensor pulses per revolution.

Set Control Source

Set Control command source to 2 / Pedal Sensor or 4 / Throttle OR Pedal Sensor.

Configure Torque Sensor

Set Torque sensor voltage source to your analog input
Set Torque sensor offset to the resting input voltage
Set Torque sensor gain using the actual sensitivity in Nm/V

Test Operation

Verify pedaling forward engages motor and stopping causes coast.

Verify with Average Pedal Speed Test

See the Average Pedal Speed Test section below.

Axle Torque Sensor (Type 5)

With the axle torque sensor connected to Throttle/Analog input 1:

Prevent Accidental Engagement

Set Control command source to 0 / Serial stream.

Enable E-Bike Flag

Enable eBike flag bit 10 under communications configuration vector.

Verify Wiring

Poll throttle voltage and apply load to verify voltage responds to torque input.

Set Sensor Type

Set Pedal sensor type to 5 / Axle torque.

Configure Gains

Set Axle torque sensor 1, Axle torque sensor 2, and Axle torque sensor 3 gains.

Set Power Gain

Set Pedalec power gain to 1 for 1:1 power gain initially.

Enable Control

Set Control command source to Pedal sensor or throttle OR pedal sensor.

Test Torque Response

Add resistance to the wheel (using trainer or brakes) and pedal at constant cadence. Verify average pedal torque increases/decreases with resistance.

Dyname Torque Sensor (Type 9)

Set Sensor Type

Set Pedal sensor type to 9 - Dyname torque sensor.

Set Voltage Source

Set Torque sensor voltage source to your input source.

Set Offset

Set Torque sensor offset to the resting sensor voltage.

Set Filter

Set Torque Sensor Voltage Filter bits (0-15):

Higher value = More filtering, slower response
Lower value = Less filtering, faster response
Averaged time = 2^value in milliseconds
Example: Value 7 = 2^7 = 128ms averaging

Set Gain

Set Torque sensor gain to calculate the torque.

Set Deadband

Set Pedalec deadband torque below which filtered torque is ignored.

Example: At 28 Nm/V gain, a 10Nm threshold = 10 Nm / 28Nm/V = 0.35V deadband.

Optional Dyname Settings

Rolling Start Enable:

Enable Features bit 9 rolling start enable
Torque will be disabled below Rolling start speed
Configure Dyname rolling start ignore torque as a threshold to bypass rolling start

Static/Stuck Torque Signal Fault Protection:

Set Throttle deadband threshold to prevent static voltage faults
Set Torque sensor static voltage fault threshold for reset voltage change
Set negative value to disable static faults entirely
Set Torque sensor static voltage fault time for fault trigger duration

Tuning Parameters

Cadence Sensor Tuning

Parameter	Effect	Recommendation
Pedalec positive motoring torque ramp	Controls assist buildup speed	Increase for softer feel
Pedalec negative motoring torque ramp	Controls assist decay speed	Application-dependent
Pedal speed map end	RPM for 100% assist	Increase for softer feel
Pedal speed map offset	Assist at 0 RPM	0 for no assist at standstill
Pedal sense delay	Pulses before assist starts	Increase to reduce sensitivity
Assist cut out distance	Distance-based timeout calculation	For speed-dependent cutout
Pedalec minimum timeout	Minimum time before negative ramp	Prevents too-quick cutout
Pedalec maximum timeout	Maximum time before negative ramp	Limits coast time

Softening bike feel: Increase Pedal speed map end and Pedalec positive motoring torque ramp from defaults (64 RPM and 200 ms).

More responsive feel: Decrease these values.

Pedal Speed Map Offset

Value > 0: Provides assist at 0 RPM when pedals are active
Value < 0: Requires positive RPM before assist begins
Value > 1: Assist request becomes 0% above Pedal speed map end

Torque Sensor Tuning

Parameter	Effect	Recommendation
Pedalec power gain	Master feel adjustment	Higher = brisker assist arrival
Pedalec torque symmetry	Torque averaging method	0 for smoothest (single-sided sensors)
Pedalec deadband torque	Minimum torque before assist	Reduce sensitivity to noise
Pedalec initial torque	Initial power on pedal start	Start at 0, increase if needed

Pedalec Power Gain Calculation

Torque assist request [%] = 100% × Average pedal torque [Nm] × Pedalec power gain / 64 Nm

Pedalec Power Gain	Full Assist (100%) at
0.5	128 Nm
1.0	64 Nm
2.0	32 Nm

Pedalec Torque Symmetry Options

Value	Mode	Best For
0	One cycle	Smoothest, single-sided sensors
1	Half cycle	Moderate responsiveness
2	Quarter cycle	Faster response
3	Instantaneous	Throttle-like feel

Average Pedal Speed Test

To verify pedal sensor configuration:

Operate pedals in the forward direction
Examine average pedal speed parameter value

Result	Meaning	Action
Positive when forward, negative when backward	Correct wiring	Configuration complete
Values reversed	Wires swapped	Swap PFS/Digital input 2 and Cruise/Digital input 1 wires
Erratic at constant cadence	Wiring issue	Check all connections

Troubleshooting

No Motor Assist When Pedaling

Check Wiring:

Single output: Power + GND + PFS/Digital input 2
Dual output: Add Cruise/Digital input 1 for cosine signal

Check Input Signals:

Single output: Verify digital inputs bit 3 (Pedal First input) toggles 0↔1
Dual output: Verify both bit 3 and bit 4 (Cruise) toggle independently

Check Signal Voltage:

Scope the sensor signals
Compare against input specifications in Connector Interface
Example issue: 1.3V/3.7V output when BAC 855 requires 4V digital low threshold

Check Motor Power Settings:

Rated motor power (Race mode PAS power) must be filled in
Rated motor power (Street mode PAS power) if using alternate power mode

Check Brake/Cutout:

eBike flags bit 1 (Cutout enabled) prevents motor engagement
Usually coupled with eBike flags bit 0 (Brake enabled)

Solutions:

Disconnect brakes if pulling voltage out of range
Set Cutoff brake sensor source out of range
Verify chosen source voltage is above Analogue brake full voltage

Motor Engages When Pedaling Backwards Only

The controller may be interpreting forward cadence as reverse direction.

Solution: Switch pedal sensor type:

From Single Hall (0) to Single Hall Reverse (6)
Or vice versa

E-Bike Flag Not Set

Enable communications configuration vector bit 10 (Enable Ebike) to enable pedal sensors.

Key Parameters Reference

Address	Parameter	Function
175	Pedal sensor type	Sensor type selection (0-9)
176	Pedal speed sensor pulses per revolution	Pulses per pedal rotation
177	Pedal sense delay	Pulses before assist starts
178	Pedal speed map end	RPM for 100% assist
179	Pedal speed map offset	Assist at 0 RPM
180	Pedalec positive motoring torque ramp	Assist ramp-up time (ms)
181	Pedalec negative motoring torque ramp	Assist ramp-down time (ms)
182	Torque sensor voltage source	Analog input selection
183	Torque sensor offset	Resting voltage (V)
184	Torque sensor gain	Sensitivity (Nm/V)
185	Pedalec power gain	Master torque multiplier
186	Pedalec torque symmetry	Averaging mode (0-3)
187	Pedalec deadband torque	Minimum torque threshold (Nm)
188	Pedalec initial torque	Initial assist boost
189	Assist cut out distance	Distance-based timeout
190	Pedalec minimum timeout	Minimum cutout delay (ms)
191	Pedalec maximum timeout	Maximum cutout delay (ms)

Next Steps

Configure Features for assist levels
Review Motor Setup for proper motor configuration
Set up Protection Systems for safe operation

Pedal Sensors

Axle Torque Legacy

Safety Warning

Configuration Tips

Set Sensor Type

Set Pulses Per Revolution

Set Control Source

Test Operation

Verify with Average Pedal Speed Test

Set Sensor Type

Set Pulses Per Revolution

Set Control Source

Configure Torque Sensor

Test Operation

Verify with Average Pedal Speed Test

Prevent Accidental Engagement

Enable E-Bike Flag

Verify Wiring

Set Sensor Type

Configure Gains

Set Power Gain

Enable Control

Test Torque Response

Set Sensor Type

Set Voltage Source

Set Offset

Set Filter

Set Gain

Set Deadband

Pedal Speed Map Offset

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