Endress+Hauser Cerabar M - 8.7 Differential Pressure Measurement (Deltabar M)

Cerabar M, Deltabar M, Deltapilot M Commissioning with an operating menu (onsite display/FieldCare)
Endress+Hauser 91
8.7 Differential pressure measurement (Deltabar M)
8.7.1 Preparatory steps
Before calibrating the device, the impulse piping must be cleaned and filled with medium.
 See the following table.
Valves Meaning Preferred installation
1Close 3.
A0030036
Above: preferred installation for gases
Below: preferred installation for liquids
I Deltabar M
II Three-valve manifold
III Separator
1, 5 Drain valves
2, 4 Inlet valves
3 Equalizing valve
6, 7 Vent valves on Deltabar M
A, B Shut-off valve
2 Fill measuring system with medium.
Open A, B, 2, 4. Medium flows in.
3 Clean impulse piping if necessary:
1)
– by blowing out with compressed air in the case of
gases
– by rinsing out in the case of liquids.
1) for arrangement with 5 valves
Close 2 and 4. Block off device.
Open 1 and 5.

Blow out/rinse out impulse
piping.
Close 1 and 5.

Close valves after cleaning.
4Vent device.
Open 2 and 4. Introduce medium.
Close 4. Close low-pressure side.
Open 3. Balance positive and low-
pressure side.
Open 6 and 7 briefly, then
close them again.
Fill device completely with
medium and remove air.
5 Set measuring point in operation.
Close 3. Shut off high-pressure side
from low-pressure side.
Open 4. Connect low-pressure side.
Now
–1

, 3, 5

, 6 and 7 are closed.
– 2 and 4 are open.
– A and B open (if present).
6 Carry out calibration if necessary.  See also page 92.
+–
A B
–
P2
+
P1
6
7
3
24
+–
A B
II
III
III
–
P2
+
P1
6
7
3
24
I
II
I
15