Mitsubishi Electric Q26UD(E)HCPU User Manual page 677

(4) Average power consumption due to voltage drop in the output section of the
output module
(power consumption for simultaneous ON points)
W = I × Vdrop × Number of output points × Simultaneous ON rate (W)
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 × 15 + I
S +15V -15V
The total of the power consumption values calculated for each block is the power consumption of the entire
programmable controller system.
W = W
According to the calculated 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 the entire programmable controller system (value obtained above)
A : Surface area inside the control panel [m
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 control panel is expected to exceed 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.
× 24 (W)
24V
+ W + W + W + W
PW 5V 24V OUT
2
]
+ W (W)
IN S
APPENDICES
A
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