A forklift, to symbolize CANopen protocol

CANopen - What is it and how does it work?

A short introduction.

CANopen is a high-level protocol originally designed for motion-oriented machine control systems. While CANopen was initially designed for motion control, it is now used in a wide variety of applications. CANopen operates on a CANbus network.

CANbus (Controller Area Network) is a vehicle bus standard that allows devices such as motor controllers, sensors, and other ECUs (electronic control units) to communicate with each other. CANbus acts as the nervous system of the vehicle, and every vehicle today is equipped with CANbus.

The Advantages of CANopen

Standardized

CANopen is a standardized protocol (ISO 11898) that making implementation of new devices straightforward, and CANopen devices can easily be configured to fit the application-specific needs. The standardized format allows tools to configure and handle the CANopen devices properly. For example, units, resolution and filtering can be set on individual devices, and designers can use off-the-shelf tools, protocols, and reuse application software.

Robust

CANopen is a robust protocol with fail-safe measures such as the heartbeat protocol, boot-up protocol, and timeout monitoring with configurable settings. These features also enable error monitoring of the signal line, allowing electromagnetic interference or other disturbances on the cable to be detected. Compared to analog signals, where it’s impossible to detect failures when the signal is within its defined limits, diagnostics can be done more accurately during operation, reducing downtime.

Simplified

CANopen also reduces the amount of cable needed for auxiliary devices. A CANopen network uses a common twisted pair cable to transmit signals, and up to 127 devices (1 master and up to 126 slaves, called Nodes in CAN language) can connect to the same bus cable. A CANopen network is flexible and can be configured with modules for easy adaptation to different needs. For example, if a large number of sensors are used for data collection, the sensors can be daisy-chained with a single cable instead of using one cable per sensor.

Explore Further

Browse our CANopen products such as pressure transmitters, rotary sensors and electric drive systems.

If you want more information, don’t hesitate to contact us.