8. Electric Panel Design
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In this case, the temperature has exceeded the limit of the equipment operation (60 °C), and must be
provided another way to remove excess heat. The limit of installed power for the internal temperature
of 60 degrees is:
Qs = k * A * (Ti – Te)
Qs = 5.5 * 3.96 * (60-30)
Qs = 653 W, 653 W limit, the remaining 347 W (1000 W - 653 W) must be removed, for example,
through an air conditioning equipment.
ATTENTION:
In previous calculations, note that the internal temperature is always a medium temperature, and if
there is no forced air circulation inside the panel, the temperature at the top of the panel will be
greater than the base, and there may be localized heat points. Proper safety margin should be given
in each case.
Figure 8-4. Examples of Heat Movement – Closed Installation
A much greater heat dissipation, comparing with previously obtained, can be reached if is allowed
the air exchange with the outside. Ventilation is normally performed with the ventilation louvers on
the sides, on the door or on the back cover. This will, of course, reduce the degree of protection (IP)
of the panel.
