CAN / CANopen
CAN bus and CANopen are the dominant industrial fieldbus protocols for HVAC equipment, chillers, variable-speed drives, and elevator controllers — offering deterministic message delivery, robust error detection, and up to 127 nodes on a single segment. These guides cover the ISO 11898-2 physical layer, CANopen CiA 301 application layer, CiA 419 HVAC device profile, and practical gateway integration into KNX, BACnet, and Modbus building automation systems.
CAN Bus Fundamentals: Physical Layer, Frame Structure and Error Detection
ISO 11898-2 High-Speed CAN physical layer — differential signalling, 120Ω termination, bit rates from 1 Mbit/s at 40m to 125 kbit/s at 500m, frame structure (SOF, arbitration ID, DLC, CRC, ACK), five error detection mechanisms, mandatory linear bus topology, non-destructive ID arbitration, and CAN FD up to 8 Mbit/s with 64-byte payloads.
CANopen in Building Automation: Object Dictionary, PDO, SDO and CiA 417/419 Profiles
CANopen application layer on CAN bus — CiA 301 object dictionary with index/sub-index structure, TPDO/RPDO process data objects for cyclic and event-driven exchange, SDO parameter read/write for commissioning, NMT state machine, SYNC and EMCY objects, CiA 417 elevator profile, CiA 419 HVAC profile for temperature setpoint, fan speed and valve position, and CANopen-to-BACnet/Modbus/KNX gateways.
CANopen HVAC Chiller Integration: Carrier, York, Daikin via Ixxat Gateway
Reading chiller data via CANopen — Carrier 30XA, York Magnitude, Daikin Skyair with CiA 419 HVAC profile object mapping for supply/return water temperature, compressor status and alarm codes, CANopen to Modbus TCP gateway configuration with Ixxat CANopen Gateway, shielded twisted-pair wiring with 120Ω termination, commissioning with PCAN-View, and resolving termination errors, bit-rate mismatches and node ID conflicts.
Need CAN/CANopen integrated into your building automation system?
We integrate CANopen devices — chillers, AHUs, variable speed drives — into KNX, BACnet and Modbus building automation systems via protocol gateways.
Request a quote →