Siemens MASS 2100 Operating Instructions Manual page 49

Penetration of humidity, liquids, or particles into the sensor must be avoided as it may influence
the measurement and, in worst case, affect the measuring function. Influence, however, can
be avoided using the following:
1. Place the sensor in a dry, clean place and leave it to acclimatize until it reaches ambient
temperature, preferred 20°C (68°F).
2. Carefully remove the plug and mount the pressure guard. Use replacement soft metal
sealing rings for proper sealing.
3. Check that the pressure guard has been correctly mounted and thoroughly tightened so
that the sealing ring fits tightly. After each dismantling, the sealing ring must always be
replaced by a new one.
Principle
Pressure guard selection
Siemens does not supply the components of the pressure guard solution because the
arrangement and components are closely related to individual safety and protection practices
in each place.
The selection of pressure guard solution is the responsibility of the user, however Siemens
recommends the following forms of pressure guard:
● A pressure switch screwed directly or piped into one of the purge ports and connected to
an automatic shut-off valve will disable pressurized supply to the meter.
● A relief valve or bursting disc screwed directly or piped to one of the purge ports to carry
any spilt fluid to drain after opening.
The pressure switch and relief valve set point should be 2-3 bar gauge. The pressure switch
should be rated to withstand the full process pressure and temperature for a short time without
rupture.
Drain flow
Ensure the drain flow is safely contained away from personnel and other plant or equipment.
MASS 2100 & FC300 (FCT030)
Operating Instructions, 06/2017, A5E39789040-AA
CAUTION
Installing/mounting
4.2 Installation instructions
49