Siemens Sinumerik 840D Series Function Manual page 81

02.99
10.03
 Siemens AG, 2003. All rights reserved
SINUMERIK 840D/SIMODRIVE 611 digital, HLA Module (FBHLA) - 10.03 Edition
0.100
Fig. 3-32 Timing of disturbance step change, integral branch of velocity controller
deactivated
Trace 1: valve spool setpoint
Trace 2: Actual velocity value
90.000
Ampl.
[dB]
10.000
1.000
180.000
Phase
[degrees]
-180.000
1.000
Fig. 3-33 Oscillogram showing velocity controlled system v
Note: Phase crossover -90 degrees essentially characterizes the
cylinder natural frequency
3.11 Start-up functions
t [ms]
log [Hz]
log [Hz]
act
3 Startup
100.000
1000.000
1000.000
/Q
act
3-81