Samson 3767, Монтаж и эксплуатация

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14 EB 8355-2 EN
Mounting on control valves
3 Mounting on control valves
The positioner can be mounted either directly
to SAMSON Type 3277 Actuator or to con-
trol valves with cast yokes or rod-type yokes
according to IEC 60534-6 (NAMUR).
Combined with an intermediate piece, the
positioner can also be mounted on rotary
actuators. The standard positioner is deliv -
ered without accessories. Any additionally
required accessories are listed together with
their order numbers in the following tables.
Do not remove the protective cover on the
back of the positioner until you actually start
to attach the positioner.
Mounting position and operating direction
The operating direction of the positioner also
determines its mounting position on the actu
-
ator as illustrated in Fig. 3, Fig. 4 and Fig. 6.
The turnboard (7 in 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 <>). Similarly, as the ref-
erence variable decreases, the signal pres-
sure can either decrease (direct action >>) or
increase (reverse action <>).
On the turnboard (7), the operating direction
is indicated by symbols (direct >>, reverse
<>). Depending on the position of the turn-
board, the adjusted operating direction and
the associated symbol become visible.
If the required operating direction does not
correspond to the visible symbol, or if you
want to change the operating direction, re -
move the fastening screw at the turnboard,
turn the board by 180° and refasten the
turnboard. Make sure the three rubber gas-
kets inserted in the housing remain in posi -
tion.
NOTICE
When any subsequent changes are
made, e.g. reversing the operating
direction of the positioner control
loop or changing the actuator fail-
safe action from “actuator stem
extends” to “actuator stem retracts”
or vice versa, the positioner's
mounting position must be changed
accordingly.
3.1 Direct attachment to
Type 3277 Actuator
Note:
The required accessories are listed in
Table 1 to Table 4 on page 18.
The attachment of the positioner either on the
left or right side of the actuator (always look
-
ing onto the signal pressure connection or
switchover plate) is determined by the re-
quired operating direction of the positioner,
i.e. >> or <>.
