Result
● The device displays the pressure measurement 0 in the set unit.
● The effective measuring range is reduced by the amount of the upstream pressure.
Example: With an upstream pressure of 100 mbar, the effective measuring range of a 1-
bar pressure transmitter is reduced to a point between 0 and 0.9 bar.
9.2.6.2
Adjusting the zero point (differential pressure)
Requirement
The pressure measurement is stable.
Procedure
1. Make sure there is identical pressure in the two process connections.
2. Navigate into the parameter view.
Navigating in the views (Page 71)
3. In the parameter view, select the "Zero point adjustment" parameter [07].
4. Press the button.
5. Set the zero point to 0.
6. Change to the measurement view with the button.
Note
Depending on the damping setting, a settling time elapses until the pressure measurement 0
is displayed.
● Make sure there is identical pressure in the two process connections until the end of the
operation.
Result
● The device displays pressure measurement 0 in the set unit.
● The effective measuring range is reduced by the amount of the upstream pressure.
Example: At a pre-load pressure of 25 mbar, the upper measuring range limit of a 250 mbar
pressure transmitter is reduced to 225 mbar.
9.2.6.3
Adjusting zero point (absolute pressure)
Requirement
You have created a reference pressure that is within the measurement limits.
Parameter assignment
9.2 Parameter assignment over device with display
SITRANS P320/P420 (mA/HART)
Operating Instructions, 06/2018, A5E44852162-AA
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