Samson 4785, Монтаж и эксплуатация

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2.3Attachment to rotary actuators
For selection of the required mounting
parts, refer to Table 6 on page 23.
The positioner can also be attached to rot-
ary actuators according to VDI/VDE 3845
by using the mounting parts and acces-
sories listed in Table 6. In this arrange-
ment, the actuator’s rotary motion is con-
verted via the cam disk on the actuator
shaft and the follower roll of the positioner
lever into a linear motion required by the
positioner’s inductive displacement sensor
system.
Each cam disk is suitable for two curves: for
angles of rotation from 0 to 90° and for
0 to 120°.
For double-acting, springless rotary actua-
tors, it is necessary that a reversing ampli-
fier be attached to the connected side of the
positioner (see section 2.3.4).
If the positioner is attached to s SAMSON
Type 3278 Rotary Actuator, the air ex-
hausted from the positioner is transferred to
the inside of the actuator and the chamber
behind the diaphragm. No additional tub-
ing is required.
If the positioner is attached to actuators by
other manufacturers (NAMUR), the air is ap-
plied to the chamber behind the diaphragm
through a tube assembly with tee, con-
nected between actuator and intermediate
piece.
2.3.1 Mounting the cam follower
roll lever
1. Place lever with the attached roll (35)
on the transmission lever (37) and se-
cure it with the enclosed screws (38)
and washers.
2.3.2 Mounting the intermediate piece
SAMSON Type 3278 Actuator:
1. Screw adapter (36) to the free end of
the rotary actuator shaft using two
screws.
2. Position intermediate piece (34) on the
actuator case and secure it with two
screws. Align the positioner’s intermedi-
ate piece so that the air connections of
the positioner face towards the dia-
phragm case side.
Actuators by other manufacturers:
1. Position complete intermediate piece
(34, 42 and 44) on fixing level 1 of the
bracket (VDI/VDE 3845) delivered with
the actuator and fasten with screws.
2. Align cam disk (40) and scale as de-
scribed in section 2.3.3. Fasten with
screws.
With springless actuators, the reversing
amplifier (45) must be screwed to the
side of the positioner case. See sec-
tion 2.3.4 for more details.
20
EB 8382-2 EN
Attaching the positioner