How to calibrate a Hall Effect sensor?
Sep 26, 2025| 1. Zero Calibration
Disconnect the measured current: Ensure the sensor input current is 0A (e.g., disconnect the measured circuit or remove the magnetic field).
Measuring the output signal:
Analog output: Use a multimeter to measure the output voltage (e.g., 0A should be 0V or 2.5V; refer to the datasheet for details).
Digital output: Read the value from a controller (e.g., PLC) (e.g., 4-20mA corresponds to 4mA).
Adjusting the zero potentiometer: Turn the "ZERO" or "Null" potentiometer on the sensor until the output returns to zero.
Software Compensation: If the sensor is connected to a control system, you can use software to set an offset to correct for zero drift.
2. Span Calibration
Applying a standard current: Apply a known standard current (e.g., 50% or 100% of full scale). Adjust the Gain Potentiometer: Turn the "GAIN" or "SPAN" potentiometer to match the output to the standard value (e.g., 5V output for 5A input).
Verify Linearity: Test multiple current points (e.g., 0%, 25%, 50%, 75%, and 100%) to ensure the output linearity error is within the allowable range.
3. Eliminate Environmental Interference
Magnetic Field Interference: Move away from strong magnetic field sources such as motors and transformers, or install a ferromagnetic shield.
Residual Magnetism Treatment: If the sensor has been exposed to a strong magnetic field, use a degaussor or follow the instructions in the manual to demagnetize it.
Installation Check: Ensure the conductor is centered (for clamp-on sensors) or the magnetic circuit is closed (for closed-type sensors) to avoid errors caused by air gaps.
4. Power Supply and Signal Verification
Power Supply Stability: Check that the supply voltage is stable (e.g., ±12V) and that the ripple exceeds the standard (recommended <5%). Wiring Check: Verify that the power and signal cables are not loose or have voltage drops (wire diameter ≥ 0.5 mm²).
5. Special Scenario Handling
Robot Applications: If used in collaborative robots, ensure that the sensor output complies with human body force safety standards (e.g., IS/TS15066).
Digital Output Type: Use a multimeter with the diode setting to check for continuity (e.g., pins ① and ② should normally be 1408 mV).
