LS Industrial Systems MASTER-K80S, Руководство пользователя

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Chapter 9 Installation and Wiring
9-
２
The following shows the procedure for calculating the PLC system power consumption.
1) PLC system power consumption block diagram
2) Power consumption of each part
(1)Power consumption of a power supply part
Approximately 70% of the power supply module current is converted into power 35% of that
65% dissipated as heat, i.e., 3.5/6.5 of the output power is actually used.
•
Wpw = 3.5 / 6.5 {(I
5V
x 5) + (I
24V
x 24)} (W)
where, l5v:
5VDC
circuit current consumption of each part
l24v:
24VDC
circuit average current consumption of output part (with points simultaneously
switched ON). Not for
24VDC
power supplied from external or power supply part that has
no
24VDC
output.
(2) Total 5VDC power consumption
The total power consumption of all modules is the power of the
5VDC
output circuit of the power
supply part.
•
W
5V
= I
5V
×
5 (W)
(3) Average DC24V power consumption (with points simultaneously switched ON)
The total power consumption of all modules is the average power of the DC24V output circuit of the power
supply part.
•
W
24V
= I
24V
×
24 (W)
(4) Average power consumption by voltage drop of output part (with points simultaneously switched ON)
•
W
out
= I
out
×
V
drop
×
output points
×
the rate of points switched on simultaneously (W)
I
out
: output current (actual operating current) (A)
V
drop
: voltage dropped across each output load (V)
Base Unit
power
supply
part
AC power
Supply
CPU part
input part output part
(transistor)
special
module
Expansion
module
I
5V
External
24VDC
power
Supply
I
24V
5VDC line
24VDC line
Load
Load
Output Current.
(IOUT)
×
Vdrop
Input Current
(
I
IN
)
×
V
drop
Input part
Output part
(Transistor)
Output
Current
(
I
OUT
)
Input
Current
(
I
OUT
)
Input
Output Current.
(
I
OUT
)
×
V
drop
Input Current
(
I
IN
)
×
V
drop
Output
Current
(
I
OUT
)
Input
Current
(
I
OUT
)