2 ventilation and pressure compensation – VEGA VEGABAR 86 Modbus and Levelmaster protocol - Operating Instructions User Manual
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4 Mounting
VEGABAR 86 • Modbus and Levelmaster protocol
46296-EN-131107
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1
Fig. 4: Temperature ranges
1 Process temperature
2 Ambient temperature
4.2 Ventilation and pressure compensation
Ventilation and pressure compensation are carried out with VE-
GABAR 86 via a filter element. It is air permeable and moisture-
blocking.
Caution:
The filter element causes a time-delayed pressure compensation.
When quickly opening/closing the housing cover, the measured value
can change for approx. 5 s by up to 15 mbar.
For effective ventilation, the filter element must always be free of
buildup.
Caution:
Do not use a high-pressure cleaner. The filter element could be dam-
aged, which would allow moisture into the housing.
The following paragraphs describe how the filter element is arranged
in the different instrument versions.
The filter element is integrated in the process assembly. It is located in
a rotatable metal ring and has the following function:
•
Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
Turn the metal ring in such a way that the filter element points down-
ward after installtion of the instrument. This provides better protection
against buildup.
Filter elements
Instruments in Ex-d ver-
sion