Toshiba V Series Manual page 53

• Thin cable trunk line: 3 A maximum
Cable length
Maximum current
(A)
• Drop line: 0.75 to 3.0 A
I: Maximum current for drop line (A)
L: Drop line length (0 to 6 m)
(2) How to determine the most appropriate arrangement of network power units
Follow the procedures below to determine the most appropriate arrangement of
network power units.
(a) Total the network currents consumed by the individual nodes on the network. For
the nodes operating on the network power, use the sum of both currents.
(b) Measure the overall length of the network.
(c) Based on the cable type (thick cable, thin cable) used for the trunk line and the
overall length of the network measured in Step b) above, obtain the maximum
current that can be supplied to the cables, referring to Figure 3-9 and Figure 3-
10.
(d) When the total current consumed by the network (obtained in Step a) is smaller
than the maximum current that can be supplied to the cables (obtained in Step c),
the network power unit installed at the network end can be used to supply the
power to all the nodes (Single power unit terminal connection).
(e) When the total current consumed by the network (obtained in Step a) is greater
than the maximum current that can be supplied to the cables (obtained in Step c),
install a network power unit near the center of the network and check whether it
can supply the power to all the nodes (Single power unit central connection).
(f) If the single power central connection is insufficient to supply the network power
to all the nodes, install additional network power units.
(3) Single Power Unit Terminal Connection
Shown below is an example of configuration where a network power unit is installed at
the end of a trunk line (thick cable) 200 meters in overall length. The current
consumption of each node is shown in the figure below.
6F8C0903
0m 10m 20m
3.00 3.00 3.00
Maximum current for thick
3.00
2.50
2.00
1.50
1.00
0.50
0.00
Figure 3-10 Trunk Line (Thin Cable) Current
Formula: I = 4.57/L (however, I<3 A)
30m 40m 50m 60m
2.06 1.57 1.26 1.06
細ケーブル最大電流
Cable lengthcable
ケーブル長
3.5 Network Power/Grounding
70m 80m 90m 100m
0.91 0.80 0.71 0.64
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