
1.CONNECTING THE DeviceNet CONNECTION B-64044EN/01
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1.7.3 Verification Using Rough Calculation by the Graph
A voltage drop occurs when a current passes through a
communication cable. The longer a communication cable is or the
larger the amount of current is, the larger a voltage drop becomes.
In addition, the voltage of the power supply for communication on
each node must be 11 VDC or higher.
The following shows, for various cable lengths, the maximum current
values for supplying a sufficient voltage to the power supply for
communication even when a voltage drop occurs.
- For thick-wire cables
Distance (m)
0 25 50 100 150 200 250 300 350 400 450 500
Max. current (A)
8.00 8.00 5.42 2.93 2.01 1.53 1.23 1.03 0.89 0.78 0.69 0.63
0
1
2
3
4
5
6
7
8
0 50 100 150 200 250 300 350 400 450 500
Distance (m)
Max. current (A)
- For thin-wire cables
Distance (m)
0 10 20 30 40 50 60 70 80 90 100
Max. current (A)
3.00 3.00 3.00 2.06 1.57 1.26 1.06 0.91 0.80 0.71 0.64
0
1
2
3
0 102030405060708090100
Distance (m)
Max. current (A)