Siemens 7MF4033 series, Руководство пользователя

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Calibration and Maintenance UMSITRPSD3-1
November 2010
7-4
7.2.3 Transmitter Enclosure Interior Inspection
Remove the two enclosure caps periodically to inspect the interior of the transmitter enclosure.
WARNING
Explosion can cause death or serious injury.
In a Division 1 area, where an explosion-proof rating is
required, remove power from the transmitter before
removing either enclosure cap.
IMPORTANT
Do not remove a transmitter enclosure cap in an area where the environmental
substances can contaminate the transmitter interior.
•
No accumulation of dust, dirt, or water (condensate) should be present inside the enclosure. If
condensate is present, either install a conduit drain or repair the installed drain (see Figure 4-16).
•
Check that all wire connections are tight.
7.2.4 Transmitter Calibration
An annual calibration check should be performed to ensure that the transmitter is within specifications.
Refer to Section 7.1 for details.
7.2.5 Impulse Piping
To ensure accuracy and continued satisfactory performance, impulse piping must be kept clean and
inspected for damage.
Sediment or other particles must not clog or collect in piping or the pressure chamber of the process
manifold’s process connection blocks. A build up of residue can cause faulty measurement.
1. Inspect impulse piping for loose, bent, or cracked piping. Replace damaged piping.
2. At regular intervals, blow down the piping without passing line fluids containing suspended solids
through the process manifold’s process connection blocks.
The time interval between blowdowns is determined by the user’s previous experience with such
systems or determined by evaluating system performance only after the transmitter has been in
operation for a period.