Endress+Hauser Cerabar S PMC71 - Page 24

Commissioning Cerabar S FOUNDATION Fieldbus
24 Endress+Hauser
5.3.1 Performing position adjustment via the onsite display or FieldCare
The parameters listed in the following table can be found in the POSITION ADJUSTMENT
group
(menu path: OPERATING MENU → SETTINGS → POSITION ADJUSTMENT).
Parameter name Description
POS. ZERO ADJUST
Entry
Position adjustment – the pressure difference between zero (set point) and the measured pressure
need not be known.
Example:
– MEASURED VALUE = 2.2 mbar
– Correct the MEASURED VALUE via the POS. ZERO ADJUST parameter with the "Confirm" option.
This means that you are assigning the value 0.0 to the pressure present.
– MEASURED VALUE (after pos. zero adjust) = 0.0 mbar
The CALIB. OFFSET parameter displays the resulting pressure difference (offset) by which the
MEASURED VALUE was corrected.
Factory setting:
0.0
POS. INPUT VALUE
Entry
Position adjustment – the pressure difference between zero (set point) and the measured pressure
need not be known. To correct the pressure difference, you need a reference measurement value (e. g.
from a reference device).
Example:
– MEASURED VALUE = 0.5 mbar
– For the POS. INPUT VALUE parameter, specify the desired set point for the MEASURED VALUE,
e.g. 2 mbar.
(The following applies: MEASURED VALUE
new
= POS. INPUT VALUE)
– MEASURED VALUE (after entry for POS. INPUT VALUE) = 2.0 mbar
– The CALIB. OFFSET parameter displays the resulting pressure difference (offset) by which the
MEASURED VALUE was corrected.
The following applies: CALIB. OFFSET = MEASURED VALUE
old
– POS. INPUT VALUE,
here: CALIB. OFFSET = 0.5 mbar – 2.0 mbar = – 1.5 mbar)
Factory setting:
0.0
CALIB. OFFSET
Entry
Position adjustment – the pressure difference between zero (set point) and the measured pressure is
known. (A reference pressure is not present at the device.)
Example:
– MEASURED VALUE = 2.2 mbar
– Via the CALIB. OFFSET parameter, enter the value by which the MEASURED VALUE should be
corrected. To correct the MEASURED VALUE to 0.0 mbar, you must enter the value 2.2 here.
(The following applies: MEASURED VALUE
new
= MEASURED VALUE
old
– CALIB. OFFSET)
– MEASURED VALUE (after entry for calib. offset) = 0.0 mbar
Factory setting:
0.0