6 Installation
6.2.2 Thermal Design of Control Panel
6-8
(2) Air Temperature Rise inside Control Panel (Average Temperature Rise)
Design the control panel so that the internal air temperature will be no more than 10
°
C higher than the refer-
ence value. If the rise in air temperature in the control panel exceeds 10
°
C, a cooling system must be installed.
For details, refer to
6.2.2 (3) Cooling System Installation
.
The calculation formula for internal temperature rise for a control panel made of metal sheets is as follows:
∆
T =
=
•
∆
T: Temperature rise in the control panel
(
°
C)
• P: Calorific value in the control panel
(W)
• qe: Heat flow through ratio of the control panel (W/
°
C)
• k: Heat pass through ratio of a metal plate
(W/m
2
°
C)
With a stirring fan: 6 W/m
2
°
C
Without a stirring fan: 4 W/m
2
°
C
• A: Effective radiation area of the control panel (m
2
)
*
∗
Radiation available area of the control panel surface area (Exclude the surface which contacts other object)
<Example>
Allowable Watt Data Loss for a Control Panel with a Stirring Fan
• Effective radiation area of the control panel: A=1.0155 (m
2
)
(Exclude the base area because control panel is type of putting on the floor.)
• Calorific value in the control panel: P=60 (W)
• Temperature rise value in the control panel:
∆
T=
=
=
=9.8 (
°
C)
This example is correct design because
∆
T is equal to 9.8 (
°
C).
P
qe
P
k
Ȇ
A
450 mm
150 mm
790 mm
P
qe
P
k
Ȇ
A
60
6
×
1.0155