34
EB 3135-1 EN
Start-up and operation
6.4.5 Adjusting actuators with
fail-safe action
Observe the relevant safety regulations on
mounting or removing the electric actuator.
The restriction in electric actuators with fail-
safe action is automatically closed when the
supply voltage is disconnected.
The actuator can be moved over the manual
override when no control signal is available.
In this case, remove the front housing cover,
place a 4 mm Allen key on the red actuating
shaft and turn it counterclockwise. Turn it on-
ly as far as the point at which the torque-de-
pendent limit switch in the actuator is activat-
ed.
Once the magnet has been released, the
spring mechanism pushes the actuator stem
back to the fail-safe position.
WARNING
!
1. Switch the control device to manual
mode and change the control signal to
retract the actuator stem all the way and
compress the spring mechanism.
2.
Use a suitable tool (Allen key, SW 4) to
turn the adjustment screw (8.3) or the set
point adjuster (8.2) clockwise (
) as far
as it will go.
3.
Refer to Fig. 6 or Fig. 7 to find out how
many turns are required to set the flow
rate.
4.
Use a suitable tool (Allen key, SW 4) to
turn the adjustment screw (8.3) or the set
point adjuster (8.2) by the required num-
ber of turns.
Turn it counterclockwise (
) to open the
restriction. The flow rate rises.
5.
Guide the wire through the lead-seal
hole and lead-seal it to fix the adjusted
flow rate.
The flow rate indicated in the diagram is re
-
duced by approximately 20 % for valves in
sizes
DN 32 to 50
which are combined with
Type 5821/5822
Actuators.
Note
