
B-63404EN/03 CONNECTION 1.CONNECTING DeviceNet FUNCTIONS
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When nodes are located to one side of the power supply (configuration example 1)
The voltage drop is calculated for each group.
Group 1 : (1×0.015+1×0.005) × 0.25=0.005V
Group 2 : (30×0.015+2×0.005) × 0.24=0.1104V
Group 3 : (50×0.015+3×0.005) × 0.50=0.3825V
Total voltage drop = 0.005 + 0.1104 + 0.3825 = 0.4979V ≥ 4.65V
So, in this configuration example, the conditional expression is not
satisfied.
When nodes are located both sides of the power supply (configuration example 2)
The voltage drop of each group is calculated for each path.
Group 1 of path 1 : (20 × 0.015+1 × 0.005) × 0.25=0.07625V
Group 2 of path 2 : (10 × 0.015+1 × 0.005) × 0.24=0.0372V
Group 3 of path 2 : (30 × 0.015+2 × 0.005) × 0.50=0.23V
Voltage drop on path 1 =0.07625V<4.65V
40mA
TerminatorTerminator
Node
Power
supply tap
50mA
Node
5 units
Node
40mA
Node
30mA
Node
8 units
Node
30mA
30mA
Node
50mA
Node
10 units
Node
50mA
50mA
30m
50m
<Group 1>
50mA+40mA×5=250mA
<Group 2>
30mA×8=240mA
<Group 3>
Communications
power supplies
Branch: thin cable
Trunk line: thick cable
power supply
40mA
Terminator
Terminator
Node
Power supply tap
50mA
Node
5 units
Node
40mA
Node
30mA
Node
8 units
Node
30mA
30mA
Node
50mA
Node
10 units
Node
50mA
50mA
20m 10m
30m
<Group 1>
<Group 2>
<Group 3>
50mA×10=500mA
Communications
power supplies
Branch: thin cable
Trunk line: thick cable
Path 1 Path 2
Communications
power supply