What problems should be paid attention to when using the hand dryer?

Hand dryer is a kind of sanitary ware appliance for drying hands or drying hands in bathroom. It is divided into induction automatic hand dryer and manual hand dryer. It is mainly used in hotels, restaurants, scientific research institutions, hospitals, public entertainment venues and toilets of every family. The hand dryer overcomes the shortcomings of the existing hand dryer that cannot blow air in multiple directions and easily cause the skin temperature of the hand to be too high. There is a wind guide device on the wind guide device. The wind guide device has a wind guide sheet. Through the rotation of the wind guide device or the swing of the wind guide sheet, the hand dryer is not directed to the wind. The working principle of the hand dryer is generally that the sensor detects a signal (hand), this signal depends on the control to open the heating circuit relay and the blower circuit relay, and start heating and blowing. When the signal detected by the sensor disappears, the contact is released, the heating circuit and the blower circuit relay are disconnected, and the heating and blowing are stopped. Symptom 1: Put the hand into the hot air outlet, no hot air blows out, only cold wind blows out. The cold wind blows out, indicating that the blower motor is working and the infrared detection and control circuit is normal. Only cold air means the heater is open or the wiring is loose. After inspection, the heater wiring is loose. After reconnecting, hot air blows out and the fault is eliminated. Symptom 2: After power on. The hand has not been placed at the hot air outlet. The hot air blows out of control. Analysis and maintenance: After investigation, there is no breakdown of the thyristor. It is suspected that the photocoupler ③ and ④ have leaking breakdown of the photosensitive tube inside the foot. After the photocoupler is replaced, the work returns to normal and the fault is eliminated. Symptom 3: Put the hand in the hot air outlet, no hot air blows out. Analysis and maintenance: check that the fan and heater are normal, measure the thyristor grid without trigger voltage, measure the c-pole of the control transistor Ⅵ has a rectangular wave signal output, suspect that the photocoupler is bad e, use a multimeter Rxl0 to block the photocoupler , ④ The forward and reverse resistances between the feet are infinite. Normally, the forward resistance should be several m, and the reverse resistance should be infinite. Can not be turned on. After replacing the photocoupler, the fault is eliminated. When choosing a hand dryer, consumers should decide which type of hand dryer to buy based on their needs and circumstances. PTC type hand dryers are different from electric wire type hand dryers. Consumers can also choose air volume type hand dryers with wind as the main heat supplement, or hot air type hand dryers with heat as the main requirement. When selecting electromagnetic induction hand dryers, it should be noted that such hand dryers are easily affected by the environment and objects. When selecting infrared sensor-type hand dryers, it is important to note that infrared sensor-type hand dryers are also susceptible to light interference. Consumers should conduct a trial machine when purchasing and choose a hand dryer that is not easily interfered with. When choosing a hand dryer, you should also pay attention to which type of motor the hand dryer uses. There are many types of motors for hand dryers, including capacitor asynchronous motors, shaded pole motors, series excited motors, DC motors, and permanent magnet motors. Hand dryers driven by capacitive asynchronous motors, shaded pole motors, and DC motors have the advantage of low noise, while hand dryers driven by series motors and permanent magnet motors have the advantage of large air volume. The latest brushless DC motors are now combined In view of the above characteristics, low noise and large air volume have become the best choice for hand dryers. Hand dryers with fast drying speed, environmental protection and energy saving are mainly wind-driven and heat-assisted. This hand dryer is characterized by high wind speed, which quickly blows off the water on the hand, and the heating function is only to maintain the comfort of the hand. The wind temperature is usually between 35-40 degrees. While drying hands quickly, there will be no burning sensation.