Fagor CNC 8070 - 4.1 Calculation of the surface needed for heat dissipation.

Hardware configuration.
CNC 8070
CENTRAL UNIT (CPU) ENCLOSURE (Q7-A PLATFORM).
4.
Calculation of the surface needed for heat dissipation.
·45·
(REF: 1911)
4.1 Calculation of the surface needed for heat dissipation.
To calculate the total surface required for the enclosure, in order to dissipate the heat
generated in it, the following data must be considered.
Heat dissipation example for an enclosure with the
recommended minimum surface.
The dissipation coefficient corresponds to an enclosure made of painted sheet metal.
In this case, for an inside temperature of 45 ºC (113 ºF), the enclosure must be larger or an
inside fan must be installed to improve heat dissipation by making the air flow inside.
Data Units Meaning
TO (m²) Total required surface (The entire surface of the enclosure except the
bottom one is considered useful).
P (W) Total power dissipated by all the elements that generate heat inside the
enclosure, including the power supply and the fan, if there is one.
Ta (ºC) Ambient temperature (outside the enclosure).
Ts (ºC) Internal CNC temperature.
Cf (m²) Dissipation coefficient of the material used for the enclosure.
Heat dissipation by natural convection. Heat dissipation by forced convection with
internal fan (flow Q = 13.6 m³/h).
C70-10K
C70-15.
C70-15AT
Ambient (room) temperature (Ta). 45 ºC (113 ºF)
Dissipated power. 24 W
Dissipating surface. 0.33 m² (3.,55 ft²)
Fan. Yes No
Air flow of the fan. 13.6
m³/h
- - -
Dissipation coefficient. 6.2 4.2
Internal CNC temperature. 56.5 ºC
133.7 ºF
62.1 ºC
143.8 ºF
Ts
A
P
Ta
A =
P
Cf · (Ts-Ta)
Ts
Ta
A
P
A
P
4,2 Ts Ta–
------------------------------=
Ts
Ta
A
P
A
P
6,2 Ts Ta–
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