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Anonymous users2024-02-121 The capacitor is reversed.
2 This phenomenon is called poor beating. The condition for this to occur is that the imagery is discontinuous; Objects have markings on the circumference. When looking at the blades of an electric fan under a fluorescent lamp, if the fan that you shoot "every frame" rotates exactly to the same position as the previous frame, you will feel that the fan is not rotating when you look at it.
If the fan is turned a little more in the same position, you will feel that the fan has only rotated a little bit when you look at it. Similarly, if the fan is turned to the same position a little less, you will feel that the *child is inverted when you look at it.
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Anonymous users2024-02-11The utility model discloses a flue-cured tobacco fan reversal alarm device, comprises two semi-circular annular bodies with the same structure, the inside of the two semi-circular annular bodies all have hollow chambers, the two semi-circular annular bodies together form a closed ring for setting and fixing on the bearing of the fan motor disc, the semi-circular annular body is horizontally arranged, the top surface of the semi-circular annular body is provided with at least one hole that communicates with the hollow chamber, and the position of the semi-circular annular body corresponds to the position of the hole and is integrally connected and upturned by the top face of the semicircular annular body, And supply the warping piece that produces alarm sound when the fan is reversed, the outer side wall of the semi-circular annular body is concave with the semicircular groove structure that extends along the radian direction of the semi-circular annular body, and the semicircular groove structure of two semicircular annular bodies on the closed ring is connected. Compared with the prior art, the utility model discloses a flue-cured tobacco fan reversal alarm device, it can not only provide whistle alarm effect when the fan is affected by three-phase electricity and appears cycle reversal phenomenon, but also can make tobacco farmers reduce the risk of flue-cured tobacco leaf bad tobacco.
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Anonymous users2024-02-10There are two reasons for this situation, one is that the range hood rotates without starting, such as outdoor wind backflow; The second is that the range hood is activated, forming a counter-rotation. It may be that in the case of the range hood starting, the reverse rotation may be the range hood air outlet check valve.
It is stuck to the oil stain and forms a reversal, etc. 1. The range hood does not start. It is caused by the backflow of outdoor wind, and a check valve is added to the exhaust pipe of the range hood to block the entry of outside air. If it is two, it is a natural phenomenon.
2. The range hood is also reversed. There is a good chance that there is a problem with the hood. The check valve of the range hood outlet is stuck with oil.
If you use the range hood for a long time, if you don't clean it regularly, it will be blocked by dirt If you guess that the check valve is stuck by the oil, it is possible to reverse, treatment method: clean the range hood. The wire is connected in the opposite direction, it is recommended to check whether the line of the wire is normal, if not, it may form a smoke reversal.
Solution: Return to the normal line. However, this kind of spike smile is unlikely.
If there is a problem with the motor, the solution is to replace the motor. The performance of the starting capacitor decreases or the starting phase changes, so that the motor sometimes rotates forward and sometimes reverses.
Solution: Replace the capacitor.
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Anonymous users2024-02-09During the use of the range hood, sometimes the fan will be reversed, which may cause the user's doubts and uneasiness, so it is very necessary to understand the reason for the fan reversal. 1.The range hood is installed in an incorrect position.
If the hood is installed in the wrong position, such as the fan is installed in reverse, or the pipe is connected in the opposite direction, this will cause the fan of the hood to reverse. If it is an installation problem, then it can be solved by simply reinstalling it. 2.
The hood is too dusty. The soot and grease accumulated inside the range hood will adhere to the wind bending machine and fan blades, thus affecting the operation of the fan. When there is a lot of accumulated dust, it will cause an imbalance when the fan rotates, which will cause the fan to reverse.
3.Range hood motor failure. The motor of the range hood is responsible for driving the fan to rotate, and if the motor fails, it will cause the fan to reverse.
If there is a motor failure, it needs to be replaced in time. 4.The range hood switch is out of order.
If the switch of the hood fails, it will also cause the fan to reverse. In this case, the switch needs to be replaced. 5.
Range hood external interference. If there are other electrical devices around the hood, such as rice cookers, microwave ovens, etc., the electromagnetic interference generated by these devices can also cause the fan to reverse. 6.
Indoor pressure is uneven. If the pressure in the room is uneven, the air flow will change, which will also cause the fan of the hood to reverse. In short, there are many reasons for the reversal of the range hood fan, which needs to be analyzed on a case-by-case basis.
If you encounter this kind of problem, it is recommended to contact the manufacturer or maintenance personnel in time for inspection and maintenance.
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The working principle of the roots fan is that the roots fan is a positive displacement fan, the air volume conveyed is proportional to the number of revolutions, and the three-lobe impeller is suction and exhaust three times by two impellers every rotation, compared with the two-blade type, the gas pulsation is less, the load change is small, the mechanical strength is high, the noise is low, and the vibration is small. Two three-bladed impellers are arranged on the shafts of two horizontal rows, and a small gap is always maintained between the wheel and the inner hole surface of the oval chassis and each impeller, and because the impellers rotate at a uniform speed in the opposite direction of each other, a certain amount of gas surrounded by the box and the impeller is transported from the side of inhalation to the side of discharge. Each impeller is always kept in the correct phase by the synchronous gear, and there will be no contact with each other, so it can be high-speed, does not require internal lubrication, and has a simple structure, stable operation, stable performance, and is suitable for a variety of purposes, and has been used in a wide range of fields. >>>More