52
English 05/09
ACCURATE AX - AW - AD - AT - AF
Type
Rated voltage
Run time at
Control
50 Hz
signal
SSB81
AC 24 V
150 s
3-position
SSB61
AC/DC 24 V
75 s
DC 0...10 V
Description
This actuator with 3point or 0÷10V signal is adapt for 2 or 3
way valve with 5,5mm stroke
Function
When the actuator is driven by DC 0…10 V control voltage or by
a 3-position signal, it produces a stroke which is transmitted to
the valve stem. The description of operation in this document
applies to the valve versions which are fully closed when deener-
gized (NC).
3-position control signal SSB81
•
Voltage at Y1: Stem extends Valve opens
•
Voltage at Y2: Stem retracts Valve closes
•
No voltage at Y1 and Y2: Actuator maintains its current position.
DC 0...10 V control signal SSB61
•
The valve opens / closes in proportion to the control signal at Y.
•
At DC 0 V, the valve is fully closed (A ? AB).
•
When power supply is removed, the actuator maintains its cur-
rent position.
Operation
A 3 mm hexagonal socket wrench can be used to move the
actuator to any position between 0 and 1. If a control signal from
the controller is present, then this takes priority in determining
the position.
Manual override
Maintenance
The actuators are maintenance-free. When carrying out service
work on the plant, following must be noted:
•
If necessary, disconnect electrical connections from the termi-
nals!
•
The actuator must be commissioned only with a correctly
mounted valve in place!
Repair
SSB... actuators cannot be repaired; the complete unit must be
replaced.
B (Y,Y2)
(Y, Y1) A
3 mm
A
B
3 mm
0
1
4891Z13
Position indicator in
position 0:
Valve closed
3
m
m
0
1
4891Z14
Position indicator in
position 1:
Valve open
