CANopen fieldbus network - technology overview

Controller Area Network

CANopen is a development of the CIA (CAN-in-Automation) international user and manufacturers group and is standardized in the European standard EN 50325-4. CANopen is a very popular industrial communication system. CANopen was originally designed for motion-oriented machine control networks, such as handling systems. By now it is used in many more industries, such as medical equipment, off-road vehicles, maritime electronics, public transportation and building automation. CANopen products are certified by the CIA user organization, guaranteeing worldwide compatibility

CANopen provides standardized communication objects for real-time data (Process Data Objects, PDO), configuration data (Service Data Objects, SDO), and special functions (Time Stamp, Sync message, and Emergency message) as well as network management data (Boot-up message, NMT message, and Error Control). All communication objects are listed in the Object Dictionary.

The Object Dictionary describes the complete functionality of a device by way of communication objects and is the interface between the communication interface and the application program.

CANopen supports both cyclic and acyclic event driven communication. This makes it possible to reduce the bus load to a minimum and maintain short reaction times. CANopen achieves high communication performance at low baud rates, thus reducing EMC problems and minimizing cable cost.

Corresponding to the CANopen specifications also device and application profiles have been published.
Generic device profiles describe just the interface of a single device. Application profiles describe all the device interfaces that are part of an application. Popular examples are the device profiles for I/O devices, electric drives, encoders or transducer and closed loop controllers.

CANOPEN FACTS
Network Type:	Multi-Master/Slave Communication system
Topology:	Line with Trunkline, Dropline structure and Termination at both Ends Line length depending on baudrate 25 - 500m
Installation :	2 wire shielded twisted pair cable Alternatively 4 wire with 24 Volt power over the bus
Data Rate :	10 kbit/s - 1 Mbit/s (selectable) kBit/s
max. Stations:	Up to 127 stations per network
Data :	Each node:        - 8 Byte unsegmented cyclic I/O Data                              - additional segmented acyclic data Total:                   - several kbyte
Network Features :	Fast and efficient communication system permitting Master/Slave, Master-Master, Multicast and Broadcast communication services.
User Organization:	CAN in Automation (CIA)

HMS is an active member of the CANopen User Organization and offers a broad range of certified CANopen products.

See Anybus products supporting the CANopen network