Endress+Hauser Deltabar S PMD75 - Parameter Description (FF Configuration Program); Block Models: Cerabar S;Deltabar S;Deltapilot S

Commissioning Deltabar S FOUNDATION Fieldbus
38 Endress+Hauser
7.6 Flow measurement
7.6.1 Preparatory steps
• The Deltabar S PMD75 is usually used for flow measurement.
• Before calibrating the Deltabar S, the pressure piping must be cleaned and the device filled
with fluid. See the following table.
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 (0.032 psi)
– 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
Input
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 (0.0073 psi)
– For the POS. INPUT VALUE parameter, specify the desired set point for the
MEASURED VALUE, e.g. 2.0 mbar (0.029 psi).
(The following applies: MEASURED VALUE
new
= POS. INPUT VALUE)
– MEASURED VALUE (after entry for POS. INPUT VALUE) = 2.0 mbar (0.029 psi)
– 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 (0.0073 psi) – 2.0 mbar (0.029 psi) = – 1.5 mbar
(0.022 psi)
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 (0.032 psi)
– 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