Download  Print this page

Advertisement

I
6. LOADING AND INSTALLATION
MELSEC-A
(3)
Power consumption of output circuits (with an average number of points
switched on)
WOUT = lout x Vdrop x average number of outputs on at one time
(W)
where, lout
= output current (actual operating current) (A)
Vdrop = voltage dropped across each output load
(V)
(4)
Power consumption of input circuits (with an average number of points
switched on)
WIN = liN
X
E x average number of inputs on at one time
(W)
Where, liN
~
input current (effective value for AC) (A)
E = input voltage (actual operating voltage) (V)
(5)
Power consumption of the special function unit power supply is ex-
pressed as:
Ws = 124v x 24
+
1100V x 100 (W)
The sum of the above values is the power consumption of the entire PC
system.
W=Wpw
+
W24V
+
WOUT
+
WIN
+
Ws (W)
Further calculations are necessary to work out the power dissipated by
the other equipment in the panel.
Generally temperature rise in the panel is expressed as;
where, W : power consumption of the entire PC system
(obtained as above)
A
panel inside surface area (m 2)
U
6
if the panel temperature is controlled by a fan, etc.
4
if panel: air is not circulated.
POINTI
Fans, heat exchangers of cooling units must be installed if the panel
temperature is likely to exceed 55°C.
Fans should be fitted with suitable filters and guards.
6-3

Advertisement

Table of Contents

   Also See for Mitsubishi Electric MELSEC-A Series

   Related Manuals for Mitsubishi Electric MELSEC-A Series

Comments to this Manuals

Symbols: 0
Latest comments: