Functional safety for SIPART PS2 FF
34
A5E00489774-02, 10/2013
C.3.5
Remedial measures table 4
Symptoms
Possible cause(s)
Remedial measures
●
In stationary automatic mode
(constant setpoint) and in manual
mode, both piezo valves continually
switch alternately, and the actuator
oscillates around a mean value.
●
Sticking friction of the packing gland
from the control valve or actuator
too large
●
Reduce friction or increase dead
zone of positioner (parameter
"dEbA") until the oscillation stops.
●
Looseness (play) in the
positioner/actuator/control valve
system
●
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.
●
Actuator too fast
●
Increase actuating times using
throttle screws.
●
If a quick actuating time is needed,
increase the dead zone (parameter
"dEbA") until the oscillation stops.
●
Positioner doesn't move control
valve to the stop (at 20 mA).
●
Supply pressure too low. Load on
the feeding controller or system
output is too low.
●
Increase supply pressure, insert
ballast converter
●
Select 3/4-wire mode
Error table 4
C.3.6
Remedial measures table 5
Fault profile (symptoms)
Possible cause(s)
Remedial measures
●
Zero point displaces sporadically
(> 3%).
●
Impact or shock loads result in
accelerations so high that the
friction clutch moves, e.g. due to
"vapor shocks" in vapor lines.
●
Rectify the causes for shock loads.
●
Re-initialize the position controller.
●
The device function has completely
failed: No representation on the
display either.
●
Electrical auxiliary power supply is
not adequate.
●
Check the electrical auxiliary power
supply.
●
In case of very high continuous
loads due to vibrations
(oscillations):
●
Screws of the electrical connecting
terminals may be loosened.
●
Electrical connecting terminals
and/or electronic components may
be knocked out.
●
Tighten the screws firmly and
secure using sealing wax.
●
Repair
●
For prevention: Install the positioner
on the damping pads.
Fault table 5
C.4
Certificate
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Certificates (
http://www.siemens.com/processinstrumentation/certificates
)
