Microsensor MDM7000 Operation Manual page 22

When the process medium is liquid, the pressure port shall be installed
horizontally or within 45° below the horizontal.
When the process medium is gas, the pressure port should be
installed vertically upwards or within 45°of the vertical upward.
When the process medium is steam, the pressure port shall be
installed horizontally or within 45°above the horizontal.
Engineering
pipeline
Liquid medium
Vent tube shall be arranged vertically or at an inclined angle. Even in
horizontal arrangements, there shall be a moderate inclination to
prevent process medium from being retained in the tube.
(2) Transmitter position
When the process medium is liquid or steam, in principle, the position
of the transmitter is lower than the pressure valve;
When the process medium is gas, in principle, the position of the
transmitter is higher than the pressure valve.
(3) Temperature difference, condensation, antifreeze, windproof
When piping, try to ensure that there is no temperature difference
between the two vent tubes, because the temperature difference may
cause changes in the density of the medium and lead to measurement
Vent tube
Gas medium
Figure 33 Pressure port
Steam medium
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