Deltabar S PROFIBUS PA
Installation
Hauser
13
4.4.1 Vacuum application (FMD78)
For applications under vacuum, Hauser recommends mounting the pressure
transmitter underneath the lower diaphragm seal. A vacuum load of the diaphragm seal caused
by the presence of filling oil in the capillaries is hereby prevented.
When the pressure transmitter is mounted above the lower diaphragm seal, the maximum
height difference H1 in accordance with the illustration below on the left must not be exceeded.
The maximum height difference is dependent on the density of the filling oil and the smallest
ever pressure that is permitted to occur at the diaphragm seal on the positive side (empty
container), see illustration below, on the right.
4.5 Heat insulation
See Operating Instructions.
P01-FMD7xxxx-11-xx-xx-xx-001
Fig. 3: Installation above the lower diaphragm
seal
P01-FMD78xxx-05-xx-xx-xx-016
Fig. 4: Diagram of maximum installation height above the lower
diaphragm seal for vacuum applications dependent on the
pressure at the diaphragm seal on the positive side
+
–
+
–
H1
–
+
0.0
2.0
4.0
6.0
8.0
1
0.0
1
2.0
50
1
00
300
400
500
600
700
800
900
1
000
200
Inert oil
High temperature
oil
Vegetable oil
Silicone oil
Pressure, diaphragm seal positive side [mbarabs]
Height
dif
ference
H
1
[m]
Low temperature oil
