The CAN bus interface CAN1 of the PowerView4 connects the PowerView4 to a CANopen® network. Via this CANopen® network, you connect the PowerView4 to the following devices:
Observe the device restrictions in the section Adding a Device.
The PowerView4 functions as NMT manager in the CANopen® network.
The wiring of the CAN bus requires three conductors (CAN Hi, CAN Lo, and CAN Com). The conductors for CAN Hi and CAN Lo must be twisted wires. At a bit rate of 250 kbit/s, the bus may only have a maximum cable length of 250 m (820') and must be terminated at both ends by a terminating resistor of 120 Ω between the CAN Hi and CAN Lo conductors to prevent reflections. Only use shielded CAN cables in compliance with the standards ISO 11898-2 and CiA® 303-1. Connect the shields of the CAN cables of all devices in the CAN bus with each other.
CAN bus termination The PowerView4 has a built-in 120 Ω terminating resistor on CAN1. In the supplied CAN cable, the corresponding connections for CAN1 termination are bridged. If the PowerView4 is not to be the first or last device in the CAN bus on CAN1, you can cut the bridges of the respective connections (see section Wiring CAN Bus Interface) once. |
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First device |
Second-to-last device |
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Second device |
Last device |
Common mode voltage in CAN bus If the CAN bus contains devices with CAN bus interfaces that are not isolated from the power supply (e.g. the I/O communication module BPlus available from MOTORTECH), error-free communication of the devices in the CAN bus is only guaranteed if the voltage levels of the signal lines CAN Hi and CAN Lo are within the range of –2 V to +7 V. If this common mode voltage range is not maintained, use a CAN bus insulator (available from MOTORTECH as accessory) for potential isolation between the interfaces. |
CAN bus wiring Note the following when connecting the CAN bus:
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The PowerView4 is delivered with a bit rate set to 250 kbit/s.
Settings on the Devices
All connected devices are designated as nodes on the CAN bus. Each node is identified by a CANopen®‑node ID. These node numbers must be indicated both in the connected devices as well as in the configuration of the PowerView4. Refer to the operating manuals of the respective devices for instructions on how to set the node ID for each device and to determine if further settings must be made to communicate via the CAN bus.
A node ID can only be assigned once within a CAN bus and must be a number between 1 and 127. Note that some devices use several node numbers. The node numbers must be assigned in the configuration after start-up of the PowerView4. Observe that the node IDs of the BPlus I/O communication modules are firmly preset (see section Device Setup PowerView4).
Overview of the CAN bus Setting up the CAN bus in the CANopen® network requires the following settings:
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CANopen® protocol If you require information on the CANopen® protocol of your PowerView4, contact your MOTORTECH contact person (see section Customer Service Information). |
Direct Connection Between PowerView4 and a Device in the CANopen® Network
If the PowerView4 is only to be connected to one supported device in the CANopen® network, you can connect the PowerView4 directly to this device using the supplied CAN cable. To do so, you need to insert the connector into the CAN connection of the PowerView4. On the respective device, connect the color-coded conductors of the CAN cable to the corresponding connections, contacts, or conductors of the device's CAN interface.
CAN1 interface on the PowerView4 |
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CAN cable
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CAN interface of the device |
The connection or contact assignment can be found in the operating manual of the supported device. Regarding the I/O communication module BPlus, refer to the section CAN Bus Wiring, CAN Bus Termination for more information.
When connecting the CAN cable shield, observe the following with the devices listed below: