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Accelnet & Stepnet Plus Panels User Guide
16-01339 Rev 07
CAN
OPEN
A
RCHITECTURE
As shown below, in a CANopen motion control system, control loops are closed in the individual drives, not
across the network. A master application coordinates multiple devices, using the network to transmit
commands and receive status information. Each device can transmit to the master or any other device on the
network. CANopen provides the protocol for mapping device and master internal commands to messages that
can be shared across the network.
CAN
A
DDRESSING
A CANopen network can support up to 127 nodes. Each node must have a unique and valid seven-bit address
(Node ID) in the range of 1-127. Address 0 is reserved for the CAN master and should only be used when the
drive is serving as a CME serial port multi-drop gateway.
The graphic above is an example of addressing for two Copley drives as the first two devices on a network
that also contains other CAN devices.
There are several methods for setting the CAN address, as described below. These method can be used in
any combination, producing a CAN address equal to the sum of the settings.
Addressing Method
Description
Address switches
If the address number <= 127, CAN address can be set using the CAN ADDR switches
only.
Digital inputs
Use the drive’s programmable digital inputs (user selects how many (1-7) and which
inputs are used).
Programmed value in
flash memory
Program the address into flash only.
For more information on CAN addressing, see the CME User Guide.
For more information on CANopen operations, see the following Copley Controls documents:
•
•
CML Reference Manual
•