User`s guide

DeviceNet Physical Layer and Media
Adept SmartController User’s Guide, Rev. K 95
For the calculation of the maximum current at a specific length, use the following formula:
Where:
l= Length of the drop line in meters (m)
i= Maximum current in amps
This calculation applies to the sum of the currents of all the nodes on the selected drop
line. The length (l) is not the cumulative length of the drop line; it is the maximum
distance from any node on the dropline to the trunk line.
It is important to note that voltage differences between the V– and V+ conductors need to
be between 11 V and 25 V. The common-mode voltage between any two places on the V–
wire must not exceed 5 V.
Table B-5. Maximum Current on a Dropline Relative to its Length
Length of Dropline Maximum Current
1.5 m (5 ft.) 3 A
2.0 m (6.6 ft.) 2 A
3.3 m (10 ft.) 1 1.5 A
4.5 m (15 ft.) 1 A
6 m (20 ft.) 0.75 A
i
4.57
l
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