1. Zero Calibration Procedure

1. Prepare for Calibration

   • Close the isolating valve completely.
   • Open the drain & test plug to release any residual pressure.
   • 

2. Check the Output Current

   • Use a multi-meter to measure the loop current of the pressure transmitter.
   • The output should be 4mA under atmospheric conditions.

3. Adjust Zero Setting

   • If the reading is not 4mA (±0.02mA), adjust the zero potentiometer on the PCB using a minus (-) screwdriver.
   • Do not adjust the span potentiometer at this stage.

4. Special Consideration for KFDO Barrier

   • If a KFDO-type barrier is installed on the manifold line, adjust the zero potentiometer to 3.80mA instead of 4mA to compensate for current consumption.
   • 

2. Span Calibration Procedure

1. Confirm System Readiness

   • Ensure that the I.S. valve for the manifold line is closed before proceeding.

2. Connect Calibration Equipment

   • Loosen the test plug and connect a 3-way valve calibration jig to the sensor.
   • Use a urethane tube to connect the pressure calibrator to the connector.

3. Apply Test Pressure

   • If the sensor range is 0–20 Bar, supply 20 Bar pressure using the calibrator.
   • Use an ammeter to monitor the output current.

4. Adjust Span Setting

   • Adjust the span potentiometer on the amplifier PCB until the output current reaches 20.00mA.
   • For systems with a KFDO barrier, adjust the span setting to 19.90mA instead of 20.00mA.

5. Fine-Tuning

   • If 20mA cannot be precisely set, compare the actual pressure reading with the local display and fine-tune the span potentiometer accordingly.

3. Final Verification

• Ensure all adjustments are correct before restoring normal operation.
• Close the drain & test plug securely after calibration.
• Verify that the transmitter displays accurate pressure values under normal conditions.