Vega VEGABAR 87 Operating Instructions Manual page 16

4 Mounting
Filter element - Position
Second Line of Defense
16
Fig. 8: Position of the filter element - Ex-d version
1 Rotatable metal ring
2 Filter element
With absolute pressure measuring ranges, a blind plug is used
instead of the filter element.
The Second Line of Defense (SLOD) is a second level of the process
separation in form of a gas-tight leadthrough in the housing neck,
preventing products from penetrating into the housing.
With these instruments, the process assembly is completely en-
capsulated. An absolute pressure measuring cell is used so that no
ventilation is required.
With relative pressure measuring ranges, the ambient pressure is
detected and compensated by a reference sensor in the electronics.
Fig. 9: Position of the filter element - gastight leadthrough
1 Filter element
2 Gas-tight leadthrough
1
2
1
1
2
2
VEGABAR 87 • 4 ... 20 mA