Mitsubishi Electric CNC 700 Series Connection Manual page 34

3. General Specifications (Environment Conditions)
The following shows an example of calculation applied to heat radiation countermeasures for the operation
panel. Because heat will accumulate in the upper portions of the unit, install an agitating fan as required.
<Calculation example of heating value in operation panel>
(1) Calculation of unit heating value
Heating value (W)
Total heating value of units (W):
27W (= display unit + operation panel I/O unit)
Total heating value (W) by machine input (D1):
5.6W (= 24V;
... 24V; current consumption per point of the operation panel I/O unit DI ÷ 3.3kΩ ≒ 7.3mA
Total heating value W = 32.6W (27 + 5.6)
Display unit
260 140
600
total heating value when the 32 points are simultaneously turned ON
15
3.5 Heat Radiation Countermeasures
(Agitating fan)
120
× 7.3mA × 32)