Siemens Sinumerik 840D Series - Page 241

10.03
A.1 Servo solenoid valves
A-241
 Siemens AG, 2003. All rights reserved
SINUMERIK 840D/SIMODRIVE 611 digital, HLA Module (FBHLA) - 10.03 Edition
The symbol also illustrates the principle of position control applied to the valve
spool.
Reset spring
OB
PT
Actuating solenoid
Position sensor
Valve amplifier
with position
control
Setpoint
U
E
=0..."10 V
OB
PT
OB
PT
Fail-safe closed Fail-safe open
Fig. A-3 Graphical symbol
A Hydraulics