Samson 4785, Mounting And Operating Instructions

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2. Attaching the positioner
The positioner can be attached either di-
rectly to the SAMSON Type 3277 Actuator,
or according to NAMUR (IEC 60534-6) to
control valves with casted or rod-type yokes.
In combination with an intermediate piece,
the device can also be attached to rotary ac-
tuators as rotary positioner.
As the positioner unit is delivered without
accessories, refer to the appropriate tables
for the order numbers of the required
mounting parts.
Note!
The positioner does not have its own vent
plug. The air is exhausted via vent plugs lo-
cated on the accessories (also see Figs. 3, 5
and 7).
Each positioner comes with a filter check
valve for the exhaust air located below the
transparent protective cap on the back of
the positioner. The standard vent plug avail-
able as an accessory must be replaced with
this filter check valve to achieve degree of
protection IP 65 protecting the device
against dirt and moisture.
2.1 Direct attachment to
Type 3277 Actuator
For selection of the required mounting
parts, refer to Tables 1, 2 and 3 on
page 15.
When looking onto the signal pressure con-
nection or the switchover plate (120 cm 2
ac-
tuator) from the top, the positioner is to be
attached to the left side of the actuator.
The arrow on the black case cover (Fig. 11)
must point towards the diaphragm cham-
ber .
Exception: Control valves in which the plug
only closes the seat area when the actuator
stem retracts. In this case, the positioner has
to be attached to the right side of the yoke
with the arrow pointing away from the dia-
phragm chamber.
1. Screw the clamp (1.2) to the actuator
stem, ensuring that the fastening screw
is located in the groove of the actuator
stem.
2. Screw associated lever D1 or D2 (for
700 cm 2 actuator) to the transmission
lever of the positioner.
3. Attach distance plate (15) with the seal
pointing towards the actuator yoke.
4. Place positioner onto the plate so that
the lever D1 or D2 slides centrically
over the pin of the clamp (1.2). Screw
positioner to distance plate (15).
5. Mount the cover (16).
240, 350 and 700 cm
2
actuators
6. Align the lateral switch plate at the con-
nection block (Fog. 3) with the arrow
12
EB 8382-2 EN
Attaching the positioner