4.7 DeviceNet System Configuration
4.7.3 Precautions for Connecting DeviceNet Communications Cables
4-42
Branching from a Drop Line
There are three methods that you can use to branch from a drop line.
4.7.3
Precautions for Connecting DeviceNet Communications
Cables
Observe the following precautions when you connect the DeviceNet communications cables.
Maximum Network Length
The maximum network length is either the length of the line between the two nodes located the
farthest from each other or the length of the line between the terminating resistance on the
ends of the trunk line, whichever is longer.
DeviceNet communications cables are available as either thick cables or thin cables. The fol-
lowing table lists the characteristics of each type of cable.
One Branch Line The Maximum of Three Branch Lines
Connecting Nodes
Directly
Drop
line
Drop
line
T-branch
adapter
SERVOPACK
Drop line
Drop
line
Drop
line
T-branch
adapter
Drop line
SERVOPACK SERVOPACK SERVOPACK
Multi-drop connection
Drop
line
Drop
line
SERVOPACK
Item
Cable Type
Thick Cable Thin Cable
Signal decay Small Large
Communications distance Long Short
Flexibility Rigid (difficult to bend) Pliable (bends easily)
Node Node Node
Node Node
Node
Node Node
T (with terminating resistance)
TT
T
T
T
Terminating resistance
: Trunk line
: Drop line
: T-branch adapter
The longer distance is the maximum network length.
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