Modbus to CANopen Gateways
Connecting Modbus Networks and CANopen Field Devices
CANopen is a fieldbus protocol built on the CAN bus
physical layer widely used for connecting sensors,
actuators, motor drives, encoders, and embedded
controllers in factory automation, machine building,
medical equipment, and mobile machinery. Modbus TCP
and RTU are the standard for supervisory systems,
PLCs, SCADA, and HMI that need to read and write
data from field devices.
When a Modbus-based control system needs to reach
CANopen field devices sending commands to CANopen
drives, reading data from CANopen sensors, or
integrating a CANopen machine network into a
Modbus TCP infrastructure a Modbus to CANopen
gateway provides the correct translation layer.
The gateway operates as a CANopen master on the
CAN bus on behalf of the Modbus host, polling
connected CANopen slave devices and mapping
their object dictionary data into Modbus TCP
registers that the controller can read and write
directly.
Understanding CANopen Configuration
CANopen integration requires more preparation than
standard Modbus deployments. Each CANopen slave device
has an Electronic Data Sheet (EDS) file that describes
its object dictionary the structured list of data
points, parameters, and control objects available on
the device. Before a CANopen master gateway can
communicate with a slave, the EDS file must be imported
and the correct Process Data Objects (PDOs) configured
for cyclic data exchange. Gateways with built-in EDS
import and auto-scan functions significantly reduce
the time required to set up a CANopen network,
particularly when multiple slave devices with different
EDS profiles are involved.
Key parameters to verify include CANopen node IDs for
each slave device, PDO communication parameters and
mapping, CANopen bus baud rate (typically 125 kbps to
1 Mbps), and CAN bus termination at both ends of the
network to prevent signal reflections.
Typical Use Cases
Modbus to CANopen gateways are deployed in machine
building and OEM applications where CANopen servo
drives, encoders, and I/O modules must be monitored
from a Modbus TCP SCADA or HMI system, in factory
automation lines where CANopen-based safety modules
and motion controllers need to exchange data with
a Modbus PLC, in material handling systems integrating
CANopen conveyor drives and positioning sensors into
a Modbus-based warehouse control system, and in
industrial vehicles and mobile machinery where
CANopen is the native fieldbus and Modbus TCP
connectivity is required for remote monitoring
or fleet management systems.
Engineering Support from Archonwell
CANopen integration requires correct EDS file
management, node ID assignment, PDO mapping, and
bus termination verification before the network
can operate reliably. Archonwell's engineering team
assists with gateway selection, CANopen network
design, EDS configuration, and Modbus register
mapping with on-site commissioning support
available for factory automation and machine
integration projects across Thailand.