Yaskawa DeviceNet Option Card CM05x - Manual (Page 25)

DeviceNet Network Wiring 4-2
DeviceNet Network Topology
The DeviceNet media has a linear bus topology. Terminating resistors are required on each end of the trunkline.
Droplines as long as 6 meters (20 feet) each are permitted, allowing one or more nodes to be attached.
DeviceNet allows branching structures only on the dropline. Figure 4.1 shows an example DeviceNet network.
The thick lines in Figure 4.1 indicate a trunkline. The thin lines in Figure 4.1 indicate a dropline.
Figure 4.1 DeviceNet Topology
Maximum Cable Distance
The total amount of trunkline allowable on the network depends upon the baud rate and the type of cable (thick or
thin) used. The cable distance between any two points in the cable system must not exceed the Maximum Cable
Distance allowed for the baud rate. For trunklines constructed of only one type of cable, refer to the following
table to determine the Maximum Cable Distance based on the baud rate and the type of cable used. Cable
distance between two points includes both trunkline cable and dropline cable length that exists between the two
points.
Baud Rate
Maximum Cable Distance for
100% Thick Cable
Maximum Cable Distance for
100% Thin Cable
125 KBaud 500 meters (1640 feet)
250 KBaud 250 meters (820 feet)
500 KBaud 100 meters (328 feet)
100 meters (328 feet)
Zero Length
Dropline
Node
Node
Node
Node
Node
Tap
Tap
Tap
Multi-Port
Tap
Node
Node
Node
Node
Node
Multi-Port
Tap
Node
Terminating
Resistor
Terminating
Resistor
Multiple Node
Daisy Chain
Dropline
Multiple Node
Branching
Dropline