4ac
2c
2a
4
2
Hydraulics Bosch Rexroth AG
RE 30111/09.05
VT-VSPA1-1 and VT-VSPA1K-1
3/12
Ramp "up/down" OFF
VT-VSPA1-1
Ramp "up" OFF
Ramp "down" OFF
VT-VSPA1K-1
Ramp OFF
The output signal of ramp generator [4] is fed as current com-
mand value to the summing amplifier [5]. Here, a command val-
ue of 100 % corresponds to a voltage of +6 V.
Functional description (continued)
Summing amplifi er [5] adds the output signals of the char ac -
ter is tic curve generators [6 or 7] to the command value (can
be se lect ed by means of DIL switches
2)
depending on the
valve to be controlled). The current command value can also be
fi ltered through a low-pass fi lter that can be cut in. Current out-
put stage [9] is controlled via current regulator [8]. In addition,
the current regulator mod u lates the current command value
with clock-pulse encoder signal [10] (the frequency can be pro-
grammed with the help of DIL switches
2)
). The clocked actual
current value acts in the solenoid of the valve like a constant
current with overlaid dither signal. Type VT-VSPA1-1 is pro-
vid ed with measuring sockets for the internal command value
and the actual value.
The following is valid for the command value: +6 V 100 %
The following is valid for the actual value: 1 mV 1 mA
The signal "ready for operation" is output and LED "H2" on the
front panel (with VSPA1-1) or LED "H2" (with VSPA1K-1) is lit,
when:
– The solenoid cables are not short-circuited and the output
stage is not overloaded,
– a command value is applied (cable break detection),
– there is no cable break present on the solenoid cable.
1)
Reference potential for command value 1 is M0 (measuring
zero).
2)
For
DIL switch settings, see "adjustment elements" on page 8
[ ] … Cross-reference to block circuit diagrams on pages 4
and 5
To Next Page
Loading...
