Omron C200HW-CORT21-V1, Руководство по эксплуатации

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Setting up a network
Section 3-3
36
CPU Unit models Max. number of
Special I/O Units
C200HE,
C200HG-CPU3
❏
-E/CPU4
❏
-E,
C200HX-CPU3
❏
-E/CPU4
❏
-E
10
C200HG-CPU5
❏
-E/CPU6
❏
-E,
C200HX-CPU5
❏
-E/CPU6
❏
-E/CPU8
❏
-ZE
CS1-series
16
3-3 Setting up a network
3-3-1 Network cabling
The wiring topology of a CAN network should be as close as possible to a
single line structure in order to avoid signal reflections from cable branches.
Stub-lines should be kept as short as possible and must be less than 30 cm
at the highest baud rate (1 Mbit/s).
Termination
ISO 11898
The bus must be terminated at both ends of the line. The cables, connectors,
and termination resistors used in CANopen networks must meet the
requirements defined in ISO 11898.
The following tables list the electrical characteristics of a CAN cable and of
the terminator according ISO 11898.
Value Cable Parameters
Minimum Nominal Maximum
Impedance [
Ω
]
108 120 132
Length-related resistance [m
Ω
/m]
70
Specific line delay [ns/m] 5
Value Terminator Parameter
Minimum Nominal Maximum
Resistance [
Ω
]
118 120 130
Cable length The maximum permissible length of the cable depends on the transmission
speed. Refer to section 1-3-7 for more details.
The market offers cables which, apart from the two data signal lines, also
provide power supply lines and shielding (CAN_GND, CAN_SHLD,
CAN_V+). This type of cable allows a central location of the network power
supply and improves protection against electromagnetic disturbances.
For industrial CAN applications, OMRON recommends the use of DeviceNet
cable, e.g. OMRON DCA1-5C10.