Samson 3767 Mounting And Operating Instructions page 16

Mounting on control valves
1. Fasten the clamp (1.2) to the actuator
stem, making sure that the fastening
screw rests in the groove of the actuator
stem.
2. Fasten the associated pick-up lever D1 or
D2 (with 355/700 cm² actuators) to the
feedback lever of the positioner.
3. Secure the intermediate plate (15) with
the gasket facing towards the actuator
yoke.
4. Position the positioner such that the pick-
up lever slides in line over the pin (1.1)
of the clamp (1.2). Fasten the positioner
to the intermediate plate (15).
5. Mount cover (16).
6. Check whether the correct range spring
has been installed as listed in Table 4.
Range spring 1 is installed as standard.
If necessary, replace it with range spring
2 included in the accessories and fix it at
the outer hook-in holes.
Actuators with 240, 350, 355, and
700 cm² diaphragm areas
7. Make sure that the tip of the gasket (16)
projecting from the side of the connec-
tion block (Fig. 3, middle) is positioned
to match the actuator symbol for the ac-
tuator's fail-safe action "actuator stem
extends" or "actuator 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-in-
sert it.
The old connection block version requires
the switch plate (13) to be turned to align
16
the actuator symbol with the arrow mark-
ing.
8. Place the connection block with the asso-
ciated gaskets against the positioner and
the actuator yoke. Fasten it using the
screw.
For actuators with fail-safe action "actua-
tor stem retracts", additionally mount the
external signal pressure pipe.
Actuator with 120 cm² diaphragm area
The signal pressure is transmitted to the dia-
phragm chamber over the switchover plate
(Fig. 3 and Fig. 4, bottom).
7. Remove screw plug on the back of the
positioner (Fig. 5) and seal the side sig-
nal pressure output with the stopper in-
cluded in the accessories.
8. Mount the positioner so that the hole in
the intermediate plate (15) covers the
seal in the hole of the actuator yoke.
9. Align the switchover plate with the corre-
sponding actuator symbol. Fasten it to
the actuator yoke.
NOTICE
If a solenoid valve or a similar device
is additionally mounted onto a
120 cm² actuator, do not remove the
M3 screw plug at the back of posi-
tioner. In this case, the signal pres-
sure must be transmitted from the sig-
nal pressure output to the actuator
over an additional connecting plate
(Table 2). The switchover plate is not
used in this case.
EB 8355-2 EN