Servo Solenoid Valve; Valve Amplifier; Shutoff Valve - Siemens SINAMICS S120 System Manual

2.1.3

Servo solenoid valve

Task
The servo solenoid valve is the final controlling element in the control loop and forms the
electro-hydraulic converter.
Function
The valve continuously converts electrical signals into hydraulic flow.
Its quality is defined by static and dynamic parameters, such as:
● Zero overlap
● Hysteresis
● Frequency limit
2.1.4

Valve amplifier

The valve amplifier contains the power electronics for the solenoids in the servo solenoid
valve, which the valve spool moves.
The position controller in the valve amplifier (onboard electronics – OBE) controls the
position of the valve spool proportionally to the manipulated variable (U = -10 ... +10 V).
2.1.5

Shutoff valve

Shutoff valves are used to add safety functions to a valve control with servo solenoid valve.
Shutoff valves can prevent uncontrolled motion of the cylinder.
Special designs include a sensor for the mechanical position of the valve spool (monitoring
for increased safety).
Hydraulic Drive
System Manual, 04/2015, 6SL3097-4BA00-0BP1
System overview
2.1 Structure of a hydraulic drive
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