
B–64193EN/01
3. INSTALLATION
19
With a small cabinet like the operator’s panel, the heat dissipating
capacity of the cabinet is as shown below, assuming that there is sufficient
mixing of the air inside the cabinet.
Coated metal surfaces: 8 W/m
2
°C
Plastic surfaces: 3.7 W/m
2
°C
An example of the thermal design for the cabinet shown in Fig. 3.4.3 is
shown below.
Air guide
chamber
120–mm square fan
motor (for air mixing)
Machine operator’s panel
Fig. 3.4.3
Assume the following.
Thermal exchange rates : Coated metal surfaces 8 W/m
2
°C
: Plastic surfaces 3.7 W/m
2
°C
: Allowable temperature rise:
13°C higher than the exteriortemperature
Also, assume the following.
Dimensions of pendant type cabinet shown in Fig. 3.4.3:
560(W) × 470(H) × 150(D) mm
Surface area of metallic sections : 0.5722 m
2
Surface area of plastic sections : 0.2632 m
2
In this case, the allowable total heat dissipation for the cabinet is:
8 × 0.5722 × 13 + 3.7 × 0.2632 × 13 = 72 W.
In consequence, it can be concluded that the units shown in Table 3.4.3
on the next page can be installed in this cabinet.
3.4.3
Thermal Design of
Operator’s Panel