Samson 5825 Mounting And Operating Instructions - Design and Principle of
1
Design and principle of
operation
The electric actuators basically consist of a
reversible synchronous motor and a mainte-
nance-free gear in a plastic housing. A cou-
pling nut (4) provides a force-locking con-
nection between the actuator and the plug
stem of the valve. For form-fit attachment, a
stem connector is used.
Type 5824 without fail-safe action
The rotary motion of the actuator motor is
transmitted to the actuator stem (3) and the
plug stem of the connected valve over a
crank disk.
When the final positions are reached or in
case of overload, the motor is switched off
by torque-dependent switches (10).
When the actuator stem retracts in actuators
with force-locking connection, the plug stem
follows the movement of the spring installed
in the valve, causing it to retract.
The valve can be manually moved to the re-
quired position with the handwheel (2).
Type 5825 with fail-safe action
The actuators with fail-safe action largely
comply with the Type 5824 illustrated in
Fig. 2. In addition, they contain a spring
mechanism (8) and an electromagnet.
When the control voltage at the electromag-
net is interrupted, the actuator moves to
fail-safe position because the electromagnet
voltage drops, causing the coupling be-
tween gear and actuator motor to
disengage. The actuator stem is completely
moved in the direction OUT or IN by the
spring mechanism.
4
EB 5824 EN
Design and principle of operation
Fig. 2 · Type 5824/5825 Actuator (front cover open), with force-locking attachment to the valve
Caution!
Do not open the back housing cover!
1
Housing
1.1 Front cover
1.2 Cable entry
2
Handwheel,
Type 5824 only
2.1 Actuating shaft
3
Actuator stem
4
Coupling nut
5
Cam disk
6
Limit switch
7.1 Adjuster for limit contact
7.2 Adjuster for limit contact
8
Spring mechanism,
Type 5825 only
9
Scale for travel indication
9.1 Driving pin
10
Torque switch
OUT
IN