Samson 3767 Mounting And Operating Instructions page 17

Air purging of the spring chamber
If the spring chamber of the actuator is to be
purged with the exhaust air from the posi-
tioner, use piping (Table 3) to connect the
spring chamber (with "actuator stem ex-
tends" version) to the connection block. To
do so, remove the stopper from the connec-
tion block. For an actuator with fail-safe ac-
tion "actuator stem retracts" and in
Type 3277
15
240 cm²
350 cm²
355 cm²
700 cm²
Type 3277-5
120 cm²
Intermediate plate (15)
Signal pressure borehole
Fig. 4: Mounting the clamp
EB 8355-2 EN
Left attachment
View onto the signal pressure connection
Clamp (1.2)
Type 3277-5 Actuators with an effective dia-
phragm area of 120 cm², the exhaust air
from the positioner is connected to the spring
chamber over an internal hole.
NOTICE
When the valve is installed, the side
cover of the actuator must be mount-
ed such that the vent plug points
downward.
Vent plug
1.2
D2
D1
Cover
Right attachment
Switchover plate
Mounting on control valves
Vent plug must point
downward when the
valve is installed
17