It is usually the most difficult information to obtain. We suggest the following methods:
In some cases it is possible to obtain from the manufacturer information of the component electrical yield. It is important to note the uncertainties introduced by the simultaneousness of the enclosure elements functioning.
With this method the heat load is calculated with a reasonable precision as long as the procedure is followed carefully.
The enclosure is put to work without any climate control and the internal and external temperatures are recorded.
When the equilibrium (final) temperature is achieved it is verified that:
Q = U x A x (Ti – Ta) where
Q = Heat Generation in the enclosure (W)
U = Heat Transmission Coefficient (W / oC x m2). Typical values are:
Carbon Steel: 5,5 W / °C x m2
Stainless Steel: 3,6 W / °C x m2
Aluminum: 6,5 W / °C x m2
(In all cases, powder coating 80 micron thickness)
A = Heat Transference Area. Its value depends on the enclosure's dimensions and its assembly lay out.
