Filter
Top Products
6 F 3 B 0 3 6 4
51
(2) How to Know the Optimal Arrangement of Network Power Units
Use the following procedure to know optimal arrangement of network power units.
a) Obtain the sum of the network currents consumed by individual nodes on the network. For the
nodes which use the network power to operate, uses the sum of both currents.
b) Measure the full length of the network.
c) Based on the cable type (thick cable, thin cable) used for the trunk line and the full length of the
network obtained through procedure b), get the maximum current value available on the cable
by using Figure 3.10 and Figure 3.11
d) When the sum of the currents consumed on the network (procedure a) is smaller than the
maximum current available on the cable (procedure c), a network power unit installed at the
network end can be used to supply the power to all nodes ( = single power unit terminal
connection).
e) When the sum of the currents consumed on the network (procedure a) is larger than the
maximum current available on the cable (procedure c), install a network power unit near the
center of the network and examine whether it can supply the power to all nodes (= single power
unit central connection).
f) If the single power central connection is insufficient to supply the network power to all nodes,
install additional network power units.
Usage Recommendation
3. Use a network power whose capacity is much larger than the total current
consumption necessary for the network.
(3) Single Power Unit Terminal Connection
Below is an example of a network power unit installed at the end of the trunk line (thick cable) with
a total extension of 200 meters. The current consumption by the node is shown below.
Network
power-supply
unit
Node 1Node 1Node 1Node 1Node 1Power tap
200 m
V
+−
V
−
0.1A 0.15A 0.05A 0.25A 0.1A
a) Sum of current consumption = 0.1A + 0.15A + 0.05A + 0.25A + 0.1A = 0.65 A
b) Total of power cable length extended = 200 m
c) Maximum current = 1.53 A available on the cable, based on Figure 3.10
d)
Since the sum of current consumption < maximum current, a single power-supply
terminal connection can supply the power to all nodes.
e) Install a network power-supply unit with a rated current of 0.65 A or more.
(Select one with ample current in considering usage conditions.)
3.12 Example of Single Power Terminal Connection