Samson 4763, Mounting And Operating Instruction

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EB 8359-2 EN 9-1
Malfunction
8 Malfunction
Risk of fatal injury due to the ignition of an
explosive atmosphere.
Î
Installation, operation or maintenance of
the positioner must only be performed by
personnel who has undergone special
training or instructions or who is autho
-
rized to work on explosion-protected de -
vices in hazardous areas.
Crush hazard arising from moving parts on
the valve.
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Do not touch any moving valve parts
while the control valve is in operation.
Î
Before performing any mounting or in -
stallation work on the positioner, put the
control valve out of operation by discon
-
necting and locking the supply air and
control signal.
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Do not impede the movement of the actu -
ator and plug stem by inserting objects
into the yoke.
8.1 Troubleshooting
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See Table 8-1
Contact SAMSON's After-sales Service for
malfunctions not listed in the table.
8.2 Emergency action
Upon failure of the air supply or electric sig-
nal, the positioner vents the actuator, causing
the valve to move to the fail-safe position de-
termined by the actuator.
Emergency action in the event of valve or ac-
tuator failure is described in the associated
valve and actuator documentation.
Î
Plant operators are responsible for emer-
gency action to be taken in the plant.
DANGER !
WARNING !
Note
Tip