Corrective Measures Table 3; Corrective Measures Table 4 - Siemens SIPART PS2 Operating Instructions Manual

12.4.4

Corrective measures Table 3

Fault profile (symptoms)
● Actuator does not move.
● Piezo valve does not switch
(however, a gentle clicking sound
can be heard when the
button is pressed in "Manual" mode.)
● A piezo valve is switched constantly
in stationary automatic mode
(constant setpoint) and in "Manual"
mode.
Fault table 3
See also
Repair/Upgrading (Page 244)
12.4.5

Corrective measures Table 4

Fault profile (symptoms)
● In stationary automatic mode
(constant setpoint) and in "Manual"
mode, both piezo valves continually
switch alternately, and the actuator
oscillates around an average value.
● Positioner doesn't move control
valve to the stop (at 20 mA).
Error table 4
SIPART PS2 with PROFIBUS PA
Operating Instructions, 05/2019, A5E00127926-AC
Possible cause
● Compressed air < 1.4 bar
● Restrictor valve turned off (screw at
the right endstop)
or
● Dirt in the pneumatic block
● Pneumatic leakage in the positioner
- actuator system; start the leakage
test in "RUN 3" (initialization).
● Dirt in the pneumatic block
Possible cause(s)
● Stiction of the packing gland from
the control valve or actuator too large
● Looseness (play) in the positioner/
actuator/control valve system
● Actuator too fast
● Supply pressure too low. Load on
the feeding controller or system
output is too low.
Diagnostics and troubleshooting
12.4 Fault correction
Corrective measures
● Set pressure of supply air PZ to
> 1.4 bar.
● Open the restrictor screw by turning
it anticlockwise, see leaflet, Fig.
⑥
"Device view ".
● Repair or a new device; clean and/or
replace the built-in fine screens.
● Rectify leakage in the actuator
and/or feed line.
● In case of an intact actuator and tight
feed line: Repair or new device
● See above
Corrective measures
● Reduce stiction or increase
deadband of positioner (parameter
"dEbA") until the oscillation stops.
● Part-turn actuator: Check for firm
seating of set screw on coupling
wheel.
● Linear actuator: Check for firm
seating of lever on positioner shaft.
● Correct any other play between the
actuator and the control valve.
● Increase travel times using throttle
screws.
● If a quick travel time is needed,
increase the deadband (parameter
"dEbA") until the oscillation stops.
● Increase supply pressure, insert
ballast converter
● Select 3/4-wire mode
279