Siemens SIPART PS2 PA 6DR55 Series, Руководство по эксплуатации

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Alarm, fault and system messages
12.4 Fault correction
SIPART PS2 with PROFIBUS communication
238
Operating Instructions, 09/2007, A5E00127926-07
12.4.4 Remedial measures table 3
Fault profile (symptoms) Possible cause Remedial measures
• Actuator does not move. • Compressed air < 1.4 bar • Set the supply air pressure to
> 1.4 bar.
• Restrictor valve turned off (screw at
the right end stop)
• Open the restrictor screw by turning
it anticlockwise, see leaflet, "Device
view (6)".
• Piezo valve does not activate (a
gentle click sound is however
audible when the "+" or "-" buttons
are pressed in the manual mode.)
• Dirt in the pneumatic block • Repair
1)
or a new device; clean
and/or replace the built-in fine
screens.
• Pneumatic leakage in the positioner
- actuator system; start the leakage
test in "RUN 3" (initialization).
• Rectify leakage in the actuator
and/or feed line.
• In case of an intact actuator and
tight feed line: repair
1)
or a new
device
• A piezo valve activates constantly in
the stationary automatic mode
(constant setpoint) and the manual
mode.
•
Dirt in the pneumatic block, see
above
•
See above
Fault table 3
1)
More information is given under the also-see link.
12.4.5 Remedial measures table 4
Fault profile (symptoms) Possible cause(s) Remedial measures
•
Static friction of the packing gland
of the control valve and the actuator
is too high
•
Reduce the static friction or
increase the dead zone of SIPART
PS2 ("dEbA" parameter) until the
oscillatory movement stops.
• Gap (play) in the positioner -
actuator - control valve system
• Part-turn actuator: Check for the
firmness of the grub screw of the
coupling wheel.
• Linear actuator: check for the
firmness of the lever on the
positioning shaft.
•
Remove any play between the
actuator and the control valve.
•
In the stationary automatic mode
(constant setpoint) and in the
manual mode, both piezo valves
are continuously activated
alternately and the actuator
oscillates to a mean value.
•
Actuator is too fast
•
Increase the actuating times using
the restrictor screws.
•
If a fast actuating time is required,
increase the dead zone ("dEBA"
parameter) until the oscillatory
movement stops.
Fault table 4