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Talking About Micro-Fans
The
function of these fans is the cooling of plates and components that generate heat. These
plates are generally part of a sofisticated equipment where high temperatures are not
allowed.
We recommend that the micro-fan always be installed in order to blow the air, because this will increase it’s efficiency.
To determine the correct dimensions of a the micro-fan it is necessary to know the degree of heat generated by the equipment that needs cooling.
The calculation of the necessary output is made by means of the following formula:
| V = 0,83 x | Wdiss | (l/s) | sendo: |
V | = | output |
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0,83 | = | coeficient | |||
| Wdiss | = | Dissipated Power | ||||
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= | difference of temperature |
Dissipated Watt: (Wdiss)
Normally
this information is obtained by the power of the heat generating component.
To examplify, a tension stabilizing source contains a heat generating transformer, which is the cause of the necessity of cooling the equipment(withdrawing hot air).
The transformer has 1,000 Watts of power. The dissipated power is approximately 10% of the device’s power. In our example the dissipated power is 100 Watts.
Difference of temperature: ()
The
difference of temperature is the difference between the internal and the external (room)
parts of the equipment. The function of the fan is to maintain the internal temperature at
maximum 5% higher than the room temperature.
Normally ,
electronic equipment is installed in rooms with air conditioning that maintains the room
temperature compatible with the equipment’s demands near to 25 ° .
Regarding the example of the stabilizing source we have
| V = 0,83 x | 100 | = 16,6 l/s |
| 5 |
With an
output of 16 l/s, the equipment type E7ALCD applies for this duty.
Installation
Whenever
possible the fan should blow directly on the heat generating source avoiding all kinds of
obstructions to the air current on it’s way out.
The output area should always be 10% larger than the input area.
| Input Area | Output Area |
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| A-Fan Area | A-Area of the Blades |
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