Siemens PROFIBUS PA SIPART PS2 Manual page 119

Fault description (symp-
toms)
CPU test blinks in the
•
display of the SIPART
PS2 (ca. every 2 secs)
Piezo valve(s) do not
•
switch
Actuator cannot be
•
moved in manual or
automatic mode, or
only in one direction
Piezo valve(s) do not
•
switch (no soft clicking
can be heard when the
+ or -- keys are
pressed in manual
mode)
Table 2
Fault description (symp-
toms)
Actuator does not
•
move
Piezo valve(s) do not
•
switch (although a
soft clicking can be
heard when the + or --
keys are pressed in
manual mode)
One piezo valve
•
constantly switches in
stationary automatic
mode (constant set-
point) and in manual
mode
Table 3
SIPART PS2 PA Manual
A5E00127926-03
Possible cause(s)
Water in the valve manifold
•
(from wet compressed air)
Dampness in the valve manifold
•
Screw between cover hood and
•
the valve manifold is not tight or
the hood is jammed
Dirt (swarf, particles) in the
•
valve manifold
Deposits on the contact(s) be-
•
tween the electronics board and
the valve manifold can occur
from abrasion through continu-
ous stresses from strong vibra-
tions
Possible cause(s)
Compressed air < 1.4 bar
•
Restrictor(s) closed down
•
(screw(s) at the right end stop)
Dirt in the valve manifold
•
Pneumatic leak in the positio-
•
ner, actuator system, start leak
test in RUN 3 (Initialization) !!!
Dirt in the valve manifold (see
•
above)
Corrective actions
At the early stages the fault can be
•
corrected by subsequent operation
with dry air (when necessary, in a
temperature cupboard at 50 to
70 °C) 70 C)
Otherwise: Repair at CSC (see
•
page 118)
Tighten screw, or release cause of
•
jamming when necessary
1)
Repair at CSC or new device with
•
integrated fine filter which can be
replaced and cleaned
Clean all contact surfaces with al-
•
cohol: when necessary bend the
valve manifold contact springs
back into place
Corrective actions
Set inlet air pressure to > 1.4 bar
•
Open restrictor screw(s) (see leaf-
•
let, Figure "View of device (6)") by
turning to the left
1)
Repair at CSC or new device
•
with integrated fine filter which
can be replaced and cleaned
Fix leak in the actuator and/or
•
supply line
If the actuator and supply line are
•
intact:
Repair of SIPART PS 2 at CSC
or new device
See above
•
Operation
1)
117