In order to create an accurate offset curve you will need to apply a fixed value to the sensor and then record the fixed value (actual value) and the value indicated on the field unit LCD display (indicated value). This will need to be done for at least 2 points and to a maximum of 22 points. As the Sensor Offset curve is configurable only from Accutech Manager and not from the LCD display on the field unit you will need to record the sensor offset points in the field and then enter them using Accutech Manager.
Step 1: Using Accutech Manager confirm that the Disable Sensor Offset Curve option is selected, and written to, the field unit to be configured.
Step 2: Record the RF channel number on the field unit and then set the RF channel to 0 to take the field unit offline.
Step 3: Perform a P ZERO on the field unit. See the Zeroing the Sensor topic for the field unit for the procedure to do this.
Step 4: Apply a sensor input using the calibration equipment and record the applied value (actual value) and the value seen on the field unit LCD display (indicated value).
Step 5: Repeat Step 4 for each point (pair of Indicated and Actual values) you wish to include in the offset curve.
- The Actual Value is the actual value that should be reported at the input level.
- The Indicated Value is the value reported by the sensor for a particular input level.
For example the recorded actual value and indicated value for a sensor with a range of 0 - 100 and with points at 0, 25, 50, 75 and 100 percent might look as follows:
Step 6: Reconnect the process and set the RF Channel to the value recorded in Step 2.
Step 7: Using Accutech Manager select the Enable Sensor Offset Curve option and set the Number of Pairs of Values to the number of points you recorded in STEP 5.
Step 8: Enter the pairs of actual values and indicated values you recorded in Step 5 in the Curve Parameters table.
Step 9: Select the Write button to write the Sensor Offset parameters to the field unit.