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Installation
4.3.5
Spring-Return Actuators
The operating principle, as explained here, is applicable for actuators with assembly code
CW (direct acting).
•
Applying supply pressure to port A will move the pistons outwards to the "Open"
position of the valve.
•
Venting the supply pressure from port A will cause the springs to move the pistons
inwards to the "Close" position of the valve.
•
For assembly codes CC, the operating principle is reversed (reverse acting):
Figure 9
Single-Acting Operation
Outward Stoke
A-port
B-port
Ps
Pilot
valve 1
3/2 Spool valve
Ra
Option: LMC
Option: Throttle 1
1.
Send control signal “Open” to the Control Module.
2.
Pilot valve 1 will be activated and the 3/2 spool valve will pressurize the central
air chamber.
3.
The piston will move outwards to the “Open” position.
4.
The Control Module indicates the “Open” position and activates feedback
signal “Open”.
16
April 2019
Installation, Operation and Maintenance Manual
DOC.IOM.BQ.E Rev. 3
Section 4: Installation