User Manual

4/20 Bosch Rexroth AG
DRC Travel Drive Control
RE 95 320/06.06
Variants DRCA, DRCB and
DRCC
The electronic drive control is designed to actuate a variable
pump in a closed hydraulic circuit.
Control is based on the following hydraulic concept:
• An A4VG or A10VG variable pump with electro-proportional
EP control combined with one or more A2FM, A2FE, A4FM
or A10FM fi xed displacement motors.
The following diesel engine confi guration can be used:
• Diesel engine with or without CAN-bus interface
The travel drive control receives the actual speed value via a
speed sensor.
Functional description
The software is used for the realization of easily reversible
hydraulic drives. Figure 1 shows a typical confi guration for the
travel drive control.
Setpoint specifi cation
The desired vehicle speed and travel direction are specifi ed
via the setpoint specifi cation. This can be performed in three
different ways:
Figure 1: Typical configuration for the DRC travel drive control, variants A-C (DRCA to DRCC)
• Variant A: Joystick
If the drive is controlled via a joystick, the setpoint and travel
direction are specifi ed via this lever. The potentiometer of the
joystick is monitored for wire break and short circuit.
• Variant B: Acceleration pedal
If the drive is controlled via an acceleration pedal, two
direction switches (for forwards/backwards travel) must also
be connected. The setpoint is specifi ed via the pedal, the
travel direction via the direction switches. The potentiometer
connected to the acceleration pedal is monitored for wire
break and short circuit.
• Variant C: External control voltage
If the drive is controlled via an external voltage, for example
via a PLC, two direction switches (for forwards/backwards
travel direction ) can also be connected. The setpoint is
specifi ed via the external control voltage, the travel direction
via a control signal or the direction switches.
Where setpoint specifi cation occurs via an external control
voltage, no monitoring is carried out by the travel drive
control. Undefi ned states at the inputs can cause the drive to
start unintentionally.
Safety monitoring must be guaranteed by the connected
signal source (e.g. PLC).
Power
supply
Ignition lock
RC2-2
controller with
DRC software
Diagnostics
socket
CAN-bus
interface
Speed limiting
Start release
signal
for starter
HG joystick valve
Two optional
direction switches
Two optional
switches for
acceleration
behavior
Optional
speed sensor
Engine
Variable pump
A4VG...EP or
A10VG...EP
Fixed displacement motor
A2FM or
A2FE or
A4FM or
A10FM
BODEM
PC
software
RS232