Type 3277 Actuator - Samson 3730-6 Mounting And Operating Instructions

Attachment to the control valve – Mounting parts and accessories

4.1.2 Type 3277 Actuator

Refer to Table 3 on page 42 or the required
mounting parts and the accessories.
Note the travel table on page 21!
Actuators with 240 to 700 cm²
Mount the positioner on the yoke as shown
in Fig. 5. The signal pressure is routed to the
actuator over the connection block (12), for
actuators with fail-safe action "Actuator
stem extends" internally through a bore in
the valve yoke and for "Actuator stem re-
tracts" through external piping.
1. Place follower clamp (3) on the actua-
tor stem, align 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 opening (Fig. 5, on
the left) pointing towards the signal
pressure connection. Make sure that the
bonded gasket (14) points towards the
actuator yoke.
3. For actuators with 355/700 cm², re-
move the follower pin (2) at lever M (1)
on the back of the positioner from pin
position 35, reposition it in the bore for
pin position 50 and screw tight.
For actuators 240 and 350 cm² with
15 mm travel, the follower pin (2) re-
mains in pin position 35.
4. Insert formed seal (15) in 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). Adjust the lever (1) correspond-
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EB 8384-6 EN
ingly and open the positioner cover to
hold the positioner shaft in position at
the cap or the switch (Fig. 21 on page
53).
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
connection block (12) is positioned
above the actuator symbol that corre-
sponds with the actuator with fail-safe
action "Actuator stem extends" or "Ac-
tuator stem retracts." If necessary, re-
move the three fixing screws and the
cover. Then reposition the gasket (16)
turned by 180°. The previous version of
the connection block (Fig. 5, bottom)
requires the switch plate (13) to be
turned such that the corresponding ac-
tuator symbol points to the marking.
7. Place the connection block (12) with the
associated seal rings against the
positioner and the actuator yoke. Screw
it tight using the fixing screw (12.1).
For actuators with fail-safe action "Ac-
tuator stem retracts", additionally re-
move the stopper (12.2) and fit on the
external signal pressure piping.
8. Mount cover (11) on the other side.
Make sure that the vent plug points
downwards when the control valve is
installed to allow any condensed water
that collects to drain off.