Mitsubishi Melsec-Q Series User Manual page 222

(3) A total of 24 VDC average power consumption of the output module
(power consumption for simultaneous ON points)
The average power of the external 24 VDC power is the total power consumption of each module.
W = I 24 Simultaneous ON rate (W)
24V 24V
(4) Average power consumption due to voltage drop in the output section of the
output module
(Power consumption for simultaneous ON points)
W = I
OUT OUT
I : Output current (Current in actual use) (A)
OUT
Vdrop : Voltage drop in each output module (V)
(5) Average power consumption of the input section of the input module
(Power consumption for simultaneous ON points)
W = I E Number of input points Simultaneous ON rate (W)
IN IN
I : Input current (Effective value for AC) (A)
IN
E : Input voltage (Voltage in actual use) (V)
(6) Power consumption of the external power supply section of the intelligent
function module
W = I 15+I
S +15V
The total of the power consumption values calculated for each block becomes the power consumption of the overall
sequencer system.
From this overall power consumption (W), calculate the heating value and a rise in ambient temperature inside the
panel.
The outline of the calculation formula for a rise in ambient temperature inside the panel is shown below.
W
T =
C
UA
W : Power consumption of overall sequencer system (value obtained above)
A : Surface area inside the panel
U : When the ambient temperature inside the panel is uniformed by a fan......6
When air inside the panel is not circulated..................................................4
If the temperature inside the panel has exceeded the specified range, it is recommended to install a heat exchanger to the
panel to lower the temperature.
If a normal ventilating fan is used, dust will be sucked into the programmable controller together with the external air, and it
may affect the performance of the programmable controller.
10 - 8
Vdrop Number of outputs Simultaneous ON rate (W)
15+I 24 (W)
-15V 24V
W = W +W +W
PW 5V
+W +W +W (W)
24V OUT IN S