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Specifications subject to change without notice
Edition: August 2017
Maintenance EB 31a-01_EN
4.10 Function and direction of rotation:
The actuator is a pneumatic component for remote actuation
of valves. For the actuation (90°, 120° or 180° rotation), there
are different actuator versions:
•
Direct mounting of a solenoid valve (5/2 or 5/3-way for
double acting, 3/2-way for single acting) for connecting to
ports 2 and 4.
•
Hook-up (to ports 2 and 4) with a separate control unit.
•
The standard direction of rotation is the clockwise
direction to close a mounted valve. The counterclockwise
direction for double-acting actuators is achieved by
applying air pressure to port 2.
•
For actuators marked “CCW”, the direction of rotation to
close the valve is counterclockwise, the clockwise
direction of rotation (CW) is achieved by applying air
pressure to port 2.
4.11 Fail-safe position:
•
Fail-close:
clockwise (SRP only)
Fig. 3 - CW direction
The standard version of the Series 31a Actuators is mounted
in the direction of the media flow.
When pressure is applied to port 2, the shaft turns from the
start position CLOSED to the end position OPEN in the
counterclockwise direction.
In case of pressure loss at port 2, the shaft turns clockwise to
the start position CLOSED (SRP only). The actuator is
delivered in the start position.
Note:
If mounted diagonal to the media flow, make
sure that the position indicator is set correctly (turn
90°, see mounting instructions
•
Fail-open:
counterclockwise (SRP only)
Fig. 4 - CCW direction
If the shaft of the actuator is to turn in a clockwise direction
when the valve opens, the pistons must be installed in the
opposite way to the standard version (see Fig. 4).
The shaft turns from the start position OPEN to the end
position CLOSED in clockwise direction (SRP only). The
actuator is delivered in the start position.
5. Actuator design und mounting instructions
The BR 31a Actuator operates with a 90° (optionally 120° or
180°) angle of rotation to open and close different types of
valves
Note:
All the necessary technical information to
correctly mount the actuator onto a valve, e.g.
dimensions, output torque, air volume, travel
adjustment, response time, operating temperature, and
direction of rotation are clearly stated on the nameplate, in
the catalog and/or data sheets.
Read the technical information carefully before proceeding
with mounting the actuator.
5.1
Principle of operation:
•
Double-acting actuator (
standard direction of rotation)
Fig. 5
Fig. 6
