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Bosch Rexroth AG
VT-MSFA1 | RE 30260-B/07.12
Information on this product
5.2 Product description
The booster amplifier is snapped onto carrier rails according to DIN 50022. The
electrical connection is established via individually removable plug-in screw con-
nectors. The module is operated with 24 V direct voltage.
The internal power supply unit supplies all internally required positive and nega-
tive supply voltages and the boost voltage for the actuator overexcitation. Thus, no
additional external voltage has to be fed in. As soon as the power supply unit is in
operation, the green LED ("Ready for operation") lights up. In case of cable break,
short circuit and internal errors, it will go out.
The booster amplifier comprises reversed polarity and short-circuit protection of
the load circuit (output stage) and reversed polarity protection of the voltage sup-
ply terminals.
A 24 V status output "Ready for operation" is available for analysis, e.g. in a PLC.
Two equivalent switching inputs (AND linked) are provided for the control of the
booster amplifier.
The booster amplifier has an integrated fast shut-down.
5.2.1 Block diagram /pin assignment
´
U
I
0 V
&
error
ok
n.c.
ok
&
1
2
3
5
6
4
IN 1
IN 2
U
B
U
Boost
U
B
U
int
error
U
Boost
U
B
U
int
DC
DC
ok
DC
DC
+U
B
3
4
1
2
7
8
5
6
Fig. 1: Block diagram VT-MSFA1
1
Power supply unit
2
Switching inputs
3
Voltage and current profile generator
4
Output stage
5
Fault recognition
6
On/off valve
5.2.2 Description of the individual components of the booster amplifier
The figures specified in brackets refer to the item numbers indicated in the
block diagram.
The internal power supply unit provides all internally required supply voltages.
If voltage is applied to one of the two switching inputs "IN1" or "IN2" (
2
), which is
less than / equal to the switch-off threshold , the output stage is switched off,
irrespective of the current phase (boost, pull-in or holding phase) and the current
actual current value. Then, there is a fast shut-down of the valve.
Power supply unit (1)
Switching inputs (2)
