Samson 3730 Series - Emergency action

9-4 EB 8384-3 EN
Malfunctions
9.2 Emergency action
Fail-safeactionistriggeredbythei/pcon-
verter or solenoid valve and upon supply air
failure. The positioner fully discharges its
pneumatic output to the atmosphere, causing
the pneumatic actuator to be vented. As a
result, the valve moves to the fail-safe posi-
tion. The fail-safe position depends on how
the springs are arranged in the pneumatic
actuator (air-to-close or air-to-open).
Whenthesupplyairfails,theoptionalsole-
noid valve or forced venting is triggered and
after reaching the shutdown signal, all posi-
tionerfunctions,exceptopen/closedloop
control, remain active (including diagnostics
as well as position and status feedback).
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.
Tip