Introduction of condenser fan motor
Although the motor fan has a high reliability, but it is still a mechanical device, in long-term use, its speed may be reduced or even stopped, so it is best to real-time monitoring of the operation of the fan, to facilitate the timely detection of problems. The alarm signal can be given when the fan speed is lower than a threshold value, and the real-time monitoring of fan speed can be realized by the output of the speed signal. The alarm signals from the fan circuit can be divided into two states: high level and low level. The meaning of the two levels is generally in the positive logic system. High level means "fault" , and low level means "normal" . The output speed signal from the fan circuit is usually in pulse form. Each wave head indicates that the FAN has turned once. Such signal can be displayed directly to the host through the data bus. Some fan output speed signal is not the true speed of the fan, but a multiple of speed, such as every turn to produce 2,4 or 6 pulse, must be processed to form the true speed signal of the fan. If you want to tell whether the fan speed is a real speed or a multiple, you can use a tachometer to measure the actual speed and then compare it with the displayed data. Fan speed signal is usually output from the three-wire plug. The yellow and black of the three leads are + 12V power supply and ground respectively. The other color is the speed signal output wire. It should be noted that the third lead of some three-lead fans is not the speed signal output line, but the speed control signal line, through which to the fan motor speed control signal input.
