21
PW20i
HBM
A1269-2.0 en/de/fr
The max. cable length is the total line length, calculated from the length of all
the spur lines per node (bus nodes) and the line length between the nodes.
The length of the spur lines per node is limited and depends on the baud rate
being used (see secondary CAN bus documentation: CiA DS102 V2.0). When
using the PW20i’s CAN wiring with CAN_In and CAN_Out lines, the length of
the spur line to the PW20i is equal to zero. If only one connection pair (CAN_In
or CAN_Out) is used, the cable length of the PW20i counts as the spur line.
Setting the address
The address is set via the bus:
CAN Bus: 1...127 (default on delivery: 63)
Setting the bit rate
The bit rate is set with the field bus configuration tool via the bus; the factory
default is 125 Kbits.
Explanations for CANopen communication can be found in the help file,
description of CANopen communication
7.3
DeviceNet interface
The interface is designed to the DeviceNet specification Release 2.0 ODVA.
Bus configuration
The DeviceNet bus is configured as a 2-wire CAN bus (CanH and CanL) (see
ISO11898). It is essential for bus termination resistors (each 120
W
) to be
connected at the start and end of the bus. The PW20i does not contain a
bus termination resistor (line termination). The structure of the bus wiring was
chosen to minimize the length of the spur lines.
Fig. 7.5:
DeviceNet bus wiring
