Siemens SITRANS P DS III - Calibrating the Sensor

Operator control functions via PROFIBUS
7.11 Calibrating the sensor
SITRANS P DS III with PROFIBUS PA
126 Operating Instructions, 06/2013, A5E00053276-07
Procedure
To simulate the sensor and electronics temperature, make the following settings:
1. Select the simulation of sensor or of the electronics temperature.
2. Set the simulation mode and the parameters:
– Simulation mode "Fixed" and parameter pressure value
– Simulation mode "Ramp" and ramp parameters
3. Transmit the settings from the program into the transmitter.
The behavior of the measured value (primary variable), the secondary variables 1, 2, and 3,
and of the output, can be observed in SIMATIC PDM.
To return to normal operation afterwards, you must turn off the simulation.
7.11
Calibrating the sensor
Sensor calibration enables you to calibrate the transmitter. Analogous to modes 19 and 20
for local operation, you can change the slope of the characteristic curve of the transmitter.
Using a lower and an upper calibration point, you can determine the course of the
characteristic curve.
Change the slope of the characteristic to a minimum of 0.9 and a maximum of 1.1. Any
larger variation from a slope of 1.0 will prevent the calibration point from being stored.
The lower calibration point must be far enough from the upper calibration point so that the
smallest calibration span is included.
The smallest calibration span is displayed in the sensor calibration dialog and depends on
the measurement range. If the calibration is smaller than the smallest span, the following
status code accompanies the measured value:
"Bad, configuration error"
In this case, recalibration the lower or the upper calibration point with a sufficiently large
calibration span.
Calibrating the lower point
To calibrate the lower point, proceed as follows:
1. Call up the dialog "Sensor calibration".
2. Apply the reference pressure for the lower calibration point.
3. Enter the value of the reference pressure in the field "lower calibration point".
4. Click on "Transmit".
In the field "Pressure cleaned raw value", observe the effect of the calibration. In the "Lower
calibration point" box, you can see whether the new calibration point was accepted.