VEGA VEGABAR 81 Profibus PA - Operating Instructions - Manual (Page 15)

15
4 Mounting
VEGABAR 81 • Profibus PA
45020-EN-131107
The filter element is mounted into the electronics housing. It has the
following functions:
•
Ventilation electronics housing
•
Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
The process assembly of instruments with Second Line of Defense
(gastight leadthrough) is completely encapsulated. An absolute pres-
sure measuring cell is used so that no ventilation is required.
1
1
Fig. 7: Position of the filter element - gastight leadthrough
1 Filter element
With relative pressure measuring ranges, the ambient pressure is
detected and compensated by a reference sensor in the electronics.
The filter element is mounted into the electronics housing. It has the
following functions:
•
Ventilation electronics housing
•
Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
1
Fig. 8: Position of the filter element - IP 69K version
1 Filter element
Instruments with absolute pressure have a blind plug mounted
instead of the filter element.
4.3 Process pressure measurement
Keep the following in mind when setting up the measuring system:
•
Mount the instrument above the measuring point
Possible condensation can then drain off into the process line.
Instruments with Second
Line of Defense
Instruments in IP 69K
version
Measurement setup in
gases