With the increasing use of cooling fans, many people are interested in the details of cooling fans. Some people will ask whether the low voltage will affect the cooling fans. Low voltage has no effect on the fan, it will only make the fan rotate at low speed, which can prolong the service life of the fan, but low voltage for a long time may damage the motor.

Voltage includes starting voltage and operating voltage. Let's first understand what are starting voltage and working voltage:

Starting voltage: refers to the minimum voltage that can start the cooling fan when it is suddenly powered on.

Operating voltage: refers to the voltage that can make the fan operate normally after power on, that is, the rated voltage.

Test method of starting voltage and operating voltage: the starting voltage can be measured by multimeter and other testing tools. The working current of the fan can be observed by ammeter.

Generally, the rated voltage of DC cooling fan is 12V and the starting voltage is generally below 7V. Because the voltage provided by the system may be unstable, the lower the starting voltage, the greater the distance from the rated voltage of 12V, which means that the wider the voltage range that the DC fan can operate, which can ensure that the starting fan can be activated at low voltage in case of unstable voltage. The operating current of the fan is low, which not only reduces the power consumption, but also reduces the calorific value of the fan motor, which can increase the service life of the fan. For the sleeve bearing fan, it can also slow down the volatilization of lubricating oil. Therefore, the lower the current, the higher the reliability of the fan. When the conveying airflow and pressure are constant, the lower the fan current, the smaller the shaft power, while the actual power transmitted to the gas is constant, and the higher the fan efficiency.

The factors affecting the starting voltage of the cooling fan are:

a. Whether the winding design is appropriate;

b. Hysteresis loss of silicon steel sheet;

c. Minimum operating voltage of hall LC;

d. Transistor magnification;

e. Magnetization strength of rubber magnet;

f. Weight of fan blade;

g. Friction coefficient of bearing;

h. Transistor saturation voltage;

i. Whether there is reverse protection diode.

The starting voltage is the minimum operating voltage of the fan, which is a characteristic to compare the advantages and disadvantages of the fan. Generally, the brushless exhaust fan with low net friction coefficient and low operating voltage is good.