Siemens SITRANS FC430, Руководство по эксплуатации

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high pressure or corrosive fluids and precautions must be taken in applications where vibrating
tube failure is probable and may cause damage.
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. Ensure the drain flow is safely contained away from
personnel and other plant or equipment.
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.
Mounting of pressure guard
All sensors are filled with argon to avoid condensation. Avoid ingress of moisture, liquids or
particles into the sensor; it may influence the measurement and in worst case inhibit the
measuring function.
Install a pressure guard as follows:
1. Place the sensor in a dry, clean place and leave it to acclimatize.
2. Orient the sensor with the purge ports uppermost.
3. Carefully remove the plug and mount the pressure guard.
4. Replace the soft metal sealing rings with new ones to obtain proper hemetic sealing.
5. Make sure that the pressure guard does NOT touch any of the parts inside the sensor.
6. Check that the pressure guard has been correctly mounted and thoroughly tightened
(torque: 80 Nm).
4.3 Disassembly
DANGER
Pressure applications
Danger to personnel, system and environment will result from improper disassembly.
● Never attempt to loosen, remove, or disassemble process connection while vessel
contents are under pressure.
Installing/mounting
4.3 Disassembly
FC430 (From firmware 4.0)
Operating Instructions, 06/2017, A5E39789392-AA
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