The WiCAN bridge connects the physical CAN-bus via a 802.11b/g/n Wi-Fi radio network. Such a network runs at layer-2 level consist of multiple bridges in order to join two or more CAN-bus segments to each other. Additionally these devices can operate in TCP/IP mode. This allows for bridging of two devices over existing network infrastructure using an encrypted TCP tunnel.
- Wireless bridge for CAN-bus data
- Operates as CANopen® device with device monitoring & configuration and SYNC regeneration
- Transparent for J1939 or other 29-bit CAN applications
- Transparent for CAN-FD
- Supports up to 8 clients in the wireless domain in Layer-2 mode
- Supports encrypted point-to-point link in TCP/IP mode
- Configuration via CANopen or using PC application via (internal) micro-USB port
- Internal button activates radio association; if no 'coordinator' is found, then it becomes the coordinator. Otherwise it pairs when the found coordinator.
- Possibility for branding or custom firmware with specific behavior
Network functions (via our gateway)
- Stream status & power level via JSON
- View status directly via HTML, no cloud needed
- Node-ID assigned via serial number
- Remote configuration & firmware update
Each of the bridge devices contains a CANopen implementation for the purpose of settings and monitoring of the remote CAN-bus segment. This function can be disabled for non-CANopen applications.
- 802.11b/g/n protocol (Wi-Fi)
- Globally approved 2.4GHz ISM band
- CANopen® interface profile wireless transmission (CiA 457 + custom)
- Large FIFO buffers allow for buffering of bursts on either side
- Separate priority FIFO helps in preserving timing of messages with ID ≤ 0x100
- Supports LSS node-ID assignment and Fastscan (CiA 305)
- Supports automatic bit-rate detection between 10kbps and 1Mbps (CiA 801)
- Up-to-date EDS file generated by and downloadable from the device
- Supports firmware update via wired or wireless CAN interface as well as via micro-USB
- Supports power management & monitoring features (CiA 302-9 + custom for monitoring of bus voltage, input current, CPU voltage and CPU temperature)
- Supports custom heartbeat messages, using additional bytes for status
- 120Ω current-limited switchable CAN-bus termination
- 6-Pin 3.81mm pluggable screw terminal for CAN-bus, ground, power, shield and earth
- Bus powered Um 12-48VDC, power <1W
- Ground and shield individually terminated to enclosure/earth via 1nF Y1 capacitors
- 6kV Surge rated; 1.2/50µs 2Ω on DC-input, 12Ω to earth, 10/700µs 25Ω on CAN-bus
- Voltage to earth clamped with 510Vrms/5kA varistor
- Capacitively isolated RP-SMA antenna connection
- Optional second antenna to provide diversity in station mode
- Conformally coated circuit board 66mm × 60mm, 4mm oblong mounting holes pitch 56-60mm
- Available with various enclosures; antistatic glass-reinforced polyester (GRP) 80×75×55mm, polycarbonate, ABS or aluminium
- ATEX increased safety 'ec' (IEC 60079-7), dust ignition protection 'tc' (IEC 60079-31)
- Customisable with industrial (M12) connection or cable assembly
Plug & Play configuration
Out of the box, the device is configured to switch to OPERATIONAL state autonomously. Wifi mode is set to L2-automatic; this means that it will start with trying to connect as station with an existing WICAN access-point. If it cannot, then it will switch mode and become a WICAN access-point itself. Their bit-rate is preset to 250kbps. The automatic bit-rate detection kicks in when bus errors occur before any valid messages have been received. After listening for all known bit-rates with no success, it reverts to the preset value and stays there.
- Bit-rate predefined to 250kbps
- Automatic switch to NMT state OPERATIONAL
- All defaults can be changed using SDO or LSS configuration
Wireless performance & limitations
Connecting CANopen devices over a wireless link strips some of the reliability and ruggedness features of the CAN bus protocol. Additionally, there are bandwidth limitations that are less easily defined than with a wire-line approach.
Use of more than 2 bridge devices in a network results in multicast transmissions, which decreases effective bandwidth proportionally to the number of bridges. When the wire-line feed bit-rate and message rate exceed the available RF bandwidth, increased message latency may occur and ultimately message loss.