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WARNING
Hot, toxic or corrosive process media
Risk of injury during maintenance work.
When working on the process connection, hot, toxic or corrosive process media could be
released.
● As long as the device is under pressure, do not loosen process connections and do not
remove any parts that are pressurized.
● Before opening or removing the device ensure that process media cannot be released.
WARNING
Improper connection after maintenance
Risk of explosion in areas subject to explosion hazard.
● Connect the device correctly after maintenance.
● Close the device after maintenance work.
Refer to Technical data (Page 191).
11.3.2
Checking the gaskets
Inspect the seals at regular intervals
Note
Incorrect seal changes
Incorrect measured values will be displayed. Changing the seals in a process flange of a
differential pressure measuring cell can alter the start-of-scale value.
● Changing seals in devices with differential pressure measuring cells may only be carried
out by personnel authorized by Siemens.
Note
Using the wrong seals
Using the wrong seals with flush-mounted process connections can cause measuring errors
and/or damage the diaphragm.
● Always use seals which comply with the process connection standards or are
recommended by Siemens.
1. Clean the enclosure and seals.
2. Check the enclosure and the seals for cracks and damage.
3. If necessary, lubricate the seals or replace them.
Service and maintenance
11.3 Maintenance and repair work
SITRANS P320/P420 (mA/HART)
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Operating Instructions, 06/2018, A5E44852162-AA