INST TECH

1. clarify job related risk and hazards and how to mitigate it                   according to the work steps,

2. Gather all information eg ILD  and DATA  sheet,

3. hand tools and test equipment must be in good condition and safe,

4. Obtain work permit with clear job steps,

5. Confirm from operation if the instrument alarm/interlock is been       buy passed for maintenance or if the control loop has been taken         in  to manual, 

CALIBRATION STEPS 

1. Connect hart communicator to check transmitter configuration e.g     calibration range ,damping are matching with data sheet also               confirm range in dcs,

2. Close process isolation valve and open drain valve, 

3.Confirm transmitter zero reading other wise adjust if required,

4.Connect pressure calibrator to transmitter port ,

5.Apply 5 point calibration method. inject pressure                                0%.25%.50%.75%.100%.  according to range check transmitter          reading in transmitter display and DCS, 

6.Repeat above same procedure for downscale reading,

7.Check the milliamp out put during calibration,

8.Zero and span calibration use hart communicator,

9.Take transmitter in service and confirm indication in DCS,

10.Do house keeping for the area, 

11.Close work permit,  

 

      The simplest example of a level measurement device is the dip stick the dip stick is long rod with a graduated scale. the dip sticks wetted portion of the scale. Indicate the height of liquid in the vessel, 
          a human operator is required to remove and read the dipstick this method can only used in small and shallow vessels, also it is used in  car and bike engine oil level measurement,