DP transmitter calibration

DP transmitter Calibration is a procedure in which we ensure the linearity and response of a DPT.

Equipments required

1. 24 VDC power supply

2. Multimeter digital

3. Pneumatic hand pump

4. Low pressure hand pump

5. High precision digital test gauge

1:- Ask panel operator to put the controller in manual mode for control loop and to put it on MOS for ESD.

2:- Hook up HART Communicator and verify some parameters by refer to data sheet. Typical parameters are, tag number, PV, LRV and URV.

3:- Remove the differential pressure transmitter from the process

4:- Make sure the equalizing valve manifold is closed.

5:- Connect H.P. tapping of the transmitter with the calibration equipment’s and L.P. tapping open to atm as shown in fig

6:- Apply the LRV pressure with the hand held test pump and check the multimeter reading, if output is not 4mA adjust zero with button or HART

7:- Apply the URV pressure with the hand held test pump and check the multimeter reading, if output is not 20mA adjust span with button or HART

8:- Verify the linearity by increasing and decreasing the pressure (0%, 25%, 50%, 75%, 100%, 75%, 50%, 25% and 0% of range)

9:- Take the transmitter in line and ensure that there is no leak.

Read Also:-

Pressure Gauge Calibration.