Bosch Rexroth Rho 4.0, Описание системы

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Electric Drives
and Controls 5−35 Bosch Rexroth AG RhoMotion 1070072367 / 04
CAN-Bus peripheral equipment
5.7 Analog In-/Outputs of the SR-CAN module
The SR-CAN modules has also 4 analog inputs besides the 8 digital in-
puts and 8 digital outputs. The analog inputs can be read by the rho4 and
processed in BAPS programs.
This description shows the possibilities of how to use the analog inputs of
the SR-CAN modules and the particularities and differences from the
analog inputs of the B~IO modules. It is to be considered as a comple-
ment to the of description ’Analog I/O with CAN B~IO modules’. The des-
cribed facts such as the setting of machine parameters for analog inputs
will form the basis.
5.7.1 CAN-bus switching
The SR-CAN module can be driven :
D
CANopen protocole
D
CANrho protocole
The protocole is selected by the setting of the machine parameter P30.
For the setting of the baud rate, the CAN knot address and the protocole,
a 8fold DIP switch is integrated on the SR-CAN module.
.
The analog ínputs of the SR-CAN modules will then be transferred
trouble-free even if the digital outputs of the module are transferred
from the rho4. (See page 5−16, CAN-I/O parameter, Machine para-
meter P30..P32).
5.7.2 Measuring ranges and data formats
The input voltage range is from −10 volts to +10 volts. The measured va-
lue read is digitally represented in a 16 bit word in the 2 complement with
sign bit doubling. In this point, the SR-CAN module differs from all B~IO
modules.
The doubling of the sign bit leads to the fact that the measuring value is
converted into a decimal number corresponding to only the half of the
real value. This particularity must be corrected by doubling the nominal
value in the machine parameter P407 (assignment of the analog input
channel).