Network length, Line length with thin or thick cable – Yaskawa SmartTrac DeviceNet Card User Manual

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SMART TRAC DeviceNet Card

Technical Manual 3554-0070 DeviceNet Basics

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Node

Terminating
Resistor

Multi-Port

Tap

Node

Multi-Port

Tap

Terminating
Resistor

Tap

Node

Multiple Node
Daisy Chain
Drop Line

Multiple Node
Branching
Drop Line

Zero Length
Drop Line

Node

Tap

Figure 3. Typical DeviceNet Topology.

In a DeviceNet network, end-to-end network (and point-to-point) distance varies
with network transmission speed (baud rate). You may use a combination of
thick and thin cable to construct trunk lines.

For trunk lines constructed of only one type of cable (either thick OR thin), refer
to Table 1. Remember that "network length" includes the combined length of
trunk line cable and drop line cable between the points.

Table 1. DeviceNet Network Length

DeviceNet Network Length

Speed
(Baud
Rate)

Maximum Length Allowed

(Thick Trunk Length)

Maximum Length Allowed

(Thin Trunk Length)

125 Kbps

1, 640 ft. (500m)

328 ft (100m)

250 Kbps

820 ft (250 m)

328 ft (100m)

500 Kbps

328 ft. (100m)

328 ft (100m)

Maximum Drop Length 20 ft (6m) (Drop line length is the longest cable
distance measured from the tap on the trunk line to each of the
transceivers of the nodes on the drop line).

Cumulative Drop Length 512 ft (156 m) at 125 Kpbs; 256 ft (78m) at
250 Kbps; or 128 ft (39m) at 500 Kbps

Data Packets: 0-8 bytes

Bus Topology: Linear (trunkline/dropline) with power and signal on the
same network cable.

Bus Addressing: Peer-to-Peer with Multi-Cast (one-to-many) or Multi-
Master and Master/Slave special case; polled or change-of-state
(exception-based)

Network Length

Line Length with Thin
or Thick Cable