ABB NCAN-02, Installation And Startup Manual

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NCAN-02 Installation and Start-up Guide 2-1
Chapter 2 – Overview
Overview
This chapter contains a short description of the CANopen protocol and
the NCAN-02 Adapter Module, a delivery checklist, and warranty
information.
CANopen CANopen is a higher-layer protocol based on the CAN (Control Area
Network) serial bus system and the CAL (CAN Application Layer).
CANopen assumes that the hardware of the connected device has a
CAN transceiver and a CAN controller as specified in ISO 11898.
The CANopen Communication Profile, CiA DS-301, includes both
cyclic and event-driven communication, which makes it possible to
reduce the bus load to minimum while still maintaining extremely short
reaction times. High communication performance can be achieved at
relatively low baud rates, thus reducing EMC problems and cable
costs.
CANopen device profiles define both direct access to drive parameter
and time-critical process data communication. The NCAN-02 fulfils CiA
(CAN in Automation) standard DSP-402 (Drives and Motion Control),
supporting the ‘Manufacturer Specific’ operating mode only.
The physical medium of CANopen is a differentially-driven two-wire
bus line with common return according to ISO 11898. The maximum
length of the bus is limited by the communication speed as follows:
The maximum theoretical number of nodes is 127. However, in
practice, the maximum number depends on the capabilities of the CAN
transceivers used.
Further information can be obtained from the CAN in Automation
International Users and Manufacturers Group (
www.can-cia.de ).
Baud Rate
Max. Bus
Length
Baud Rate
Max. Bus
Length
1 Mbit/s 25 m 125 kbit/s 500 m
800 kbit/s 50 m 50 kbit/s 1000 m
500 kbit/s 100 m 20 kbit/s 2500 m
250 kbit/s 250 m 10 kbit/s 5000 m