Pressure Transmitter Calibration and Troubleshooting Guide
Regular calibration ensures pressure transmitters provide accurate measurements for process control and safety applications.
I. Calibration Procedure
- Isolate the transmitter from the process using the manifold valves
- Connect a pressure calibrator or deadweight tester to the high pressure side
- Vent the low pressure side to atmosphere (for gauge pressure calibration)
- Apply pressure at calibration points from zero to one hundred percent in twenty-five percent steps
- Record the output at each point for both increasing and decreasing pressure
- Calculate errors and adjust trim if the error exceeds specifications
II. Troubleshooting
Output Stuck at Zero or Minimum: Check for reversed impulse lines. Verify that the transmitter is not in simulation mode.
Output Above Range: Check for overpressure condition. Verify the range configuration matches the actual process pressure. Check for sensor damage.
Drifting Output: Check for temperature changes beyond compensation limits. Verify power supply stability. Check for moisture in the electronics housing.
Noisy Output: Check for process pulsations. Increase damping. Verify that impulse lines are not partially plugged.
