Siemens SINAMICS S120 System Manual page 40

Configuration
3.3 Configuring the hydraulics
Flow rate characteristic, linear/with transition point
Valves with either a linear characteristic or with transition point characteristic can be
selected. Valves with a characteristic with a transition point are suitable for obtaining a
higher resolution in the low signal range (machining) and sufficient flow rate in the high
signal range (rapid traverse).
The definition of the transition point position as 40 % or 60 % means that only 10% of the
nominal opening cross-section (nominal flow rate) is released for 40 % or 60 % of the
nominal control signal (i.e. at U=4 V or 6 V).
The valve characteristic with transition point must be linearized in the HLA module to adapt it
to the closed-loop control of the entire drive (cylinder).
Figure 3-2
Note
Recommended selection
Servo solenoid valves are generally recommended for applications where there is a clear
separation between machining operation and rapid traverse.
40
Diagram of a servo solenoid valve characteristic with transition point and its
compensation in the HLA module
System Manual, 04/2015, 6SL3097-4BA00-0BP1
Hydraulic Drive