Samson Type 3766, Монтаж и эксплуатация

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2 Attachment to control valve
The positioner can be attached either di-
rectly to a SAMSON Type 3277 Actuator
or to valves with cast yokes or rod-type
yokes according to IEC 60534-6 (NAMUR).
When combined with an intermediate
piece, the device can also be attached to
rotary actuators as a rotary positioner.
As the positioner is also available as a
basic unit without accessory equipment,
refer to the tables on the following pages
for both the required mounting parts and
their associated order numbers.
Do not remove the protective cover on the
positioner’s rear side before actually start-
ing to attach the positioner.
Mounting position and operating direction
The operating direction of the positioner
also determines its mounting position on the
actuator as illustrated in Figs. 3, 4, and 6.
The turnboard (7, Fig. 2) at the positioner
must be mounted correspondingly.
For an increasing input signal (reference
variable), the signal pressure p
st
can either
be increasing (direct action >>) or decreas-
ing (reverse action <>).
This also applies when the reference vari-
able decreases: direct action >> causes the
signal pressure to decrease, reverse ac-
tion <> causes the signal pressure to in-
crease.
On the turnboard (7), the operating direc-
tion is indicated by symbols (direct >>,
reverse <>).
Depending on the position of the turnboard,
the adjusted operating direction and the as-
sociated symbol become visible.
If the required operating direction does not
correspond to the visible symbol, or if you
want to change the operating direction,
remove the fastening screw at the turn-
board, turn the board by 180°, and re-
fasten the turnboard with the screw. Make
sure the three rubber gaskets inserted in the
housing remain in position.
Important!
When any subsequent changes are made,
e.g. reversing the operating direction of the
positioner control loop or changing the actu-
ator from “Actuator stem extends” to “Actu-
ator stem retracts” or vice versa, the posi-
tioner’s mounting position must be changed
accordingly.
2.1 Direct attachment to
Type 3277 Actuator
Required accessories are listed in Tables 1
to 4 on page 14.
The attachment of the positioner either on
the left or right side of the actuator (always
looking at the signal pressure connection or
switchover plate) is determined by the re-
quired operating direction of the positioner,
i.e. >> or <> .
10
EB 8355-1 EN
Attachment to control valve