Samson 5857 - Indication with Leds; Direction of Action Switch

EB 5857 EN 6-3
Operation
6.1.2.1 Indication with LEDs
The actuator with positioner has a red and a yellow LED which indicate the operating state of
the actuator through a blinking pattern. The LEDs are located underneath the cover on top of
theactuator(seeFig.6-2).
6.1.2.2 Direction of action switch
The position of the direction of action switch determines the actuator's direction of action.
Î SeeFig.6-2.
− Switch position A: Direction of action increasing/increasing (>>)
The actuator stem retracts as the input signal increases.
− Switch position B: Direction of action increasing/decreasing (<>)
The actuator stem extends as the input signal increases.
Actuator stem extended
− For globe valves: Valve closed
− For three-way mixing valves: Port A à AB open, B à AB closed
− For three-way diverting valves: Port AB à A closed, AB à B open
Actuator stem retracted
− For globe valves: Valve open
− For three-way mixing valves: Port A à AB closed, B à AB open
− For three-way diverting valves: Port AB à A open, AB à B closed
A
B
AB
AB
A
B
A
AB
B
AB
A
B
Mixing valve for mixing service
Diverting valve for mixing service
For diverting service
For diverting service
Flow pipe
Flow pipe
Flow pipe
Flow pipe
Returnowpipe
Returnowpipe
Returnowpipe
Returnowpipe
Fig.6-3: Operating principle of three-way mixing and diverting valves