Mounting The Positioner; Mounting Sequence; Lever And Pin Position - Samson 3725 Mounting And Operating Instructions

Mounting the positioner

4 Mounting the positioner
The Type 3725 Positioner is suitable for the
following types of attachment:
− Direct attachment to SAMSON
Type 3277 and Type 2780-2 Actuators
− Attachment to actuators according to
IEC 60534-6 (NAMUR)
− Attachment to Type 3372 Actuator
(Series V2001 Valves)
− Attachment to rotary actuators according
to VDI/VDE 3845
Applies to all types of attachment:
Î Do not mount the positioner with the
vent opening (Fig. 2) facing upward.
Î Do not seal the vent opening.

4.1 Mounting sequence

Mount the positioner, keeping the following
sequence:
1. Use correct lever and pin position. Refer
to section 4.2.
2. Mount the positioner on the control
valve. Refer to section 4.3 ff.
3. Connect the supply air. Refer to sec-
tion 5.1.
4. Connect the electric reference variable.
Refer to section 5.2.
5. Perform start-up. Refer to section 7.

4.2 Lever and pin position

The positioner is adapted to the actuator and
to the rated travel by the lever on the back of
12
the positioner and the pin inserted into the
lever.
The travel tables on page 13 show the as-
signment between the required lever and pin
position.
The positioner is equipped with the M lever
(pin position 35) as standard.
Removing the lever and changing the pin
position:
NOTICE
Incorrect removal of the lever will
damage the positioner.
Only remove the lever when it is po-
sitioned at the bottom mechanical
stop.
1. Hold the lever in place. Undo the nut us-
ing a wrench (width across flats SW 10).
2. Remove the lever from the shaft.
3. Insert pin in position as listed in the trav-
el table.
4. Fasten the lever.
Top stop
Bottom
stop
Fig. 2: Mechanical stops and vent opening
Vent opening
EB 8394 EN