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6

Difficult to say without seeing the switches and wiring, but I would suspect a bad connection or wiring fault somewhere. You do not say if it has always been like this or if the fault has developed recently. One of the wire terminals on the switches may be lose or corroded, or maybe at the lamp, motor or distribution board. I would very much doubt that the ...


3

Controlling a DC motor by simply controlling the voltage is called armature voltage control or adjustable voltage control. That is not really the opposite of pulse width modulation. It is a different way of doing the same thing. You might say it is an analog method rather than a digital method. Controlling the current is a method of controlling torque. That ...


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You can't get there from here :-). You need to specify what you mean by speed control. Unless the range of speeds is within a very small range below synchronous speed then you cannot reasonably open-loop control the speed of an induction motor by varying the drive power. And you can only closed loop control it in a reasonable manner withing a relatively ...


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Unless the load is a fan or centrifugal pump, the same torque will be required to drive the load at the lower speed. Your power calculation implies that the torque will be the same. The power will be reduce to about 70% of rated because power is torque multiple by speed. However current is proportional to torque, so the current will not be reduced. VFDs are ...


2

Assuming this is a standard colour code it looks to me like we have green, blue, red, black. Three-phase motors will often not have a neutral. We know that green is going to be a protective earth wire. This leaves blue, red, and black. The United States of America and Canada each have these colours: The United States of America: 1. Black, 2. Red, 3. ...


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just hook it up. if the motor runs in the wrong direction, just reverse 2 of the phases


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The / provides the nominal ratings at different operating conditions. On the high end: 75% duty cycle, when the motor drives a 0.28kW load the rated current is 0.95A, spins at 2660 rpm, geared down to 176 rpm has a pf of 0.85. Low end: 25% duty cycle, 0.071kW load at 0.75A, spins at 650 rpm, geared down to 43 rpm has a pf of 0.75. The motor is connected ...


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Cheap usually has poor quality. If you must buy a cheap motor because you do not have enough money to buy a good motor then you do not need a motor. Take a bus instead. I would use a DC brushless motor because it does not have brushes that wear out and has a wide RPM range without losing much torque. With the wide RPM range then the car might not need a ...


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The iron in the field magnet structure will retain some magnetism even without any current in the winding so the field and hence the back-emf will not drop to zero. The actual remaining amount depends upon the specifics of the material and the magnetic structure. Dynamos rely upon this remanence to bootstrap operation at start-up.


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Servo motors use current to force coils to create rotor torque from Magneto-motive force MMF. They are "often" called voice coils for the reason that the electro-mechanical motion sounds like a speaker. (unintentionally) Generally, many devices have software options to reduce acceleration to reduce the frequency range of acoustic emissions. This is a ...


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Single-phase motors are not a good choice for speed control. Triac controllers control the motor voltage. That works reasonably well if the motor is driving a fan or centrifugal pump. Even with fans and pumps, some motor designs are not suitable. With that type of load, the required torque decreases a lot as the speed is reduced. Water or air flow and motor ...


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I need to know Rated power.( This has a code. I cant understand that.) The two power ratings, 0.07 kW and 0.28 kW are the ratings at the two motor speeds, 650 RPM and 2660 RPM. That would be consistent with two-speed operation with full torque available at each of the two speeds. I believe "S3-25/75% designates a duty cycle. If you search "S3 motor duty ...


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The fundamental thing to worry about is Power. Your motor has a particular maximum power output. It has a continuous power output limited by heat dissipation, and a peak power output, limited by the capacity to absorb heat. Your wheelchair needs power to accelerate it (probably not the limiting factor), power to roll it against its friction (probably not ...


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I had a similar problem using a Pololu boost regulator to drive a motor. Placing capacitors before and after the regulator made the problem worse. The regulator drew a lot of power but failed to reach the full output voltage. My conclusion was that the high initial load caused the bench power supply current limit to kick in, at several times the expected ...


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I have had good results controlling the speed of this sort of fan with a regular light dimmer - the kind that chops up the AC wave with a Triac. You can't let the speed drop too much - if it's running very slowly then a change of wind or temperature could make it stop, and then it might be damaged. But for control between 50% and 100%, a dimmer should work ...


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Add a capacitor in series with the motor. This is how wall plate speed controls, for overhead ceiling fans, work. Look here, I want to control motor speed with capacitors. ... and be super careful when working with the AC line.


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If the motor is designed to run in star a 380V 3-phase power supply, then it cannot be connected in delta on the 'same' supply. This is similar to applying 380 volt to 220 v windings so clearly the motor would fail. The solution is either to get a 3 phase step down transformer to get 220 3 phase voltage and you need to calculate the ratings if the KVA of ...


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