WIKA ISO 9001 Mode D'emploi page 14

5. Commissioning, operation
Maximum permissible height differences in mounting
■
For pressure measuring instruments above the measuring point (see example 1 and 2),
the following applies:
H1 ≤ 7 m for system fill fluid: Silicone, glycerine or paraffin oil
EN
H
≤ 4 m for system fill fluid: Halocarbon oil
1
For measurements of negative overpressure, the permissible height difference must be
reduced accordingly.
Example 1
With absolute pressure measurements (vacuum), the measuring instrument must at least
be mounted at the same height as the diaphragm seal or beneath it (see example 3 and 4).
Example 3
Vacuum
14
Example 2
Example 4
Vacuum
WIKA operating instructions, diaphragm seal systems