YASKAWA DX200 Instructions Manual page 63

165626-1CD
JARCR-XFB01B Board
for DeviceNet
7 Connections for DeviceNet Communications
7.1 Location of Communication Power Supply
Example 1: Where the power supply is at the end of the
trunk line
The following diagram shows an example where the thick cable with the
total length of 210 m is used and the power supply is connected at the
end of the trunk line.
Terminator
Node
0.2A
Communications
Power Supply
Total length of the power supply cable = 210 m
Total current consumption of the nodes = 0.2A + 0.1A + 0.05A + 0.2A +
0.15A
= 0.7A
Max. current obtained from the graph = 1.5A
As A (total current consumption) < B (max. current), sufficient
communications power can be supplied to all nodes.
Example 2: Where the power supply is in the middle of the
trunk line
The following diagram shows an example where the thick cable with the
total length of 240m is used and the power supply is connected in the
middle of the trunk line.
Trunk Line
Terminator
Node Node
0.2A 0.3A
120m
Total length of the power supply cable on the left of the power supply=
Total length of the power supply cable on the right of the power supply
= 120m
Total current consumption of the nodes on the left of the power supply=
0.2A + 0.3A + 0.1A = 0.6A
Total current consumption of the nodes on the right of the power supply=
0.25A + 0.15A + 0.1A = 0.5A
The maximum current on the left obtained from the graph = approx. 2.5A
The maximum current on the right obtained from the graph = approx. 2.5A
As A (total current consumption on the left) < B (maximum current on the
left) and A (total current consumption on the right) < B (maximum current
on the right), sufficient power can be supplied to all nodes.
7-6
Trunk Line
Node Node Node
0.1A 0.05A 0.2A
210m
Trunk Line
Node Node
0.1A 0.25A
Communications
Power Supply
120m
HW1481973
Terminator
Node
0.15A
: Trunk Line
: Power Supply Cable
Terminator
Node
Node
0.15A 0.1A
: Trunk Line
: Power Supply Cable
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