Omron OMNUC W R88A-NCW152-DRT, Manual

Page: 49 / 292

4 Connectors
4.5.3 DeviceNet Network Configuration Restrictions
4-18
4
Note
There are no restrictions in the number of nodes that can be connected to a single drop line, but a
maximum of 64 nodes total can be connected to a single network, including the DeviceNet Master
Unit.
When a DeviceNet Configurator is not used to allocate Remote I/O with SYSMAC CS/CJ series or
C200HX/HG/HE PC, a maximum of 51 nodes total can be connected to a single network, includ-
ing the DeviceNet Master Unit. When a DeviceNet Configurator is not used to allocate Remote I/
O with C200HS series PC, the maximum is 33 nodes, including the DeviceNet Master Unit.
4.5.3 DeviceNet Network Configuration Restrictions
To enable the widest possible application of DeviceNet communications, the baud rate can
be selected and the connection methods can be freely combined using both T-branch and
multi-drop connections.
This section describes the restrictions required in DeviceNet communications to achieve this
wide range of application.
„ Baud Rate and Communications Distance
The maximum length of the DeviceNet communications lines depends on the baud rate and
the type of cable that is used.
The DeviceNet communications lines are restricted in the following three ways.
• Maximum network length
• Drop line length
• Total drop line length
Design and install the DeviceNet network to meet all of these restrictions to ensure reliabil-
ity in communications.
Trunk line
Trunk line
Trunk line
Trunk line
Drop
line
Drop line
Drop line
Node Node Node
Node
Node
Node
Node
Node
Node
Node
24 VDC
Communications
power supply
Power Supply
Tap or T-branch Tap
With
terminating
resistor
With
terminating
resistor