Type 3277 Actuator - Samson Series 3730 Mounting And Operating Instructions

4.1.2 Type 3277 Actuator
− Required mounting parts and accesso-
ries: Table 2 on page 53
− Observe the travel table on page 22.
Actuators with 175 to 750 cm² effective ar-
eas (see Fig. 4)
Mount the positioner on the yoke. The signal
pressure is routed to the actuator over the
connection block (12), for actuators with fail-
safe action "actuator stem extends" internal-
ly through a hole in the valve yoke and for
"actuator stem retracts" through an external
pipe.
1. Place follower clamp (3) on the actuator
stem, align it and screw tight so that the
mounting screw is located in the groove
of the actuator stem.
2. Mount cover plate (10) with narrow side
of the cut-out (Fig. 4, on the left) pointing
towards the signal pressure connection.
Make sure that the gasket (14) points to-
wards the actuator yoke.
3. For actuators with 355, 700 or 750 cm²,
remove the follower pin (2) on the M le-
ver (1) on the back of the positioner from
pin position 35, reposition it in the hole
for pin position 50 and screw tight.
For actuators 175, 240 and 350 cm²
with 15 mm travel, keep the follower pin
(2) in pin position 35.
4. Insert formed seal (15) into the groove of
the positioner housing.
5. Place positioner on the cover plate in
such a manner that the follower pin (2)
rests on the top of the follower clamp (3).
EB 8384-6 EN
Attachment to the control valve – Mounting parts and accessories
Adjust the lever (1) correspondingly and
open the positioner cover to hold the po-
sitioner shaft in position at the cap or ro-
tary pushbutton. The lever (1) must rest
on the follower clamp with spring force.
Mount the positioner on the cover plate
(10) using the two fixing screws.
6. Make sure that the tip of the gasket (16)
projecting from the side of the connec-
tion block is positioned to match the ac-
tuator symbol for the actuator's fail-safe
action "actuator stem extends" or "actu-
ator stem retracts". If this is not the case,
unscrew the three fastening screws and
lift off the cover. Turn the gasket (16) by
180° and re-insert it.
The old connection block version (Fig. 4,
bottom) requires the switch plate (13) to
be turned to align the actuator symbol
with the arrow marking.
7. Place the connection block (12) with the
associated seals against the positioner
and the actuator yoke and fasten using
the screw (12.1). For actuators with fail-
safe action "actuator stem retracts", ad-
ditionally remove the stopper (12.2) and
mount the external signal pressure pipe.
8. Mount cover (11) on the other side.
Make sure that the vent plug is located at
the bottom when the control valve is in-
stalled to allow any condensed water
that collects to drain off.
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