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1 vote

Fundamental understanding of motor torque

At the risk of duplicating what others have answered, let me try. According to my understanding of physics, torque causes angular acceleration, which tends to increase the rotational/angular speed. ...
• 58.1k

Fundamental understanding of motor torque

Real motors generally have a torque (measured at the shaft) which drops to zero at some speed for a given input. That is due to friction and "windage" (air resistance on the rotor) as well ...
• 328k
1 vote

Fundamental understanding of motor torque

Every motor has a particular torque-speed characteristic curve which tells us how much torque does the motor provide at a given speed Yes and no: the torque speed curve is a rated limit, usually for ...
• 620

Fundamental understanding of motor torque

So if the load is being supplied with some torque by the motor, then how is it rotating at a constant speed? Shouldn't it accelerate due to the motor torque? the electromotive force produces a torque ...
1 vote

Fundamental understanding of motor torque

Yes, if the motor is applying torque and there is no energy lost (to mechanical loads, electrical losses, or just to friction), the shaft will accelerate. But there's always electrical losses and ...
• 19.4k
1 vote

Tesla’s AC motor: questions on operation

Iron is randomly oriented dipoles and can be very lossy in high BH fields. Grain-oriented rolled steel laminates have the advantage of dipole alignment and the thinner layers between insulated ...
1 vote

Tesla AC motor: operational question with field direction

Yes except the rotor is different and only 2 poles /rev. C=C and opposite to C'=C' so commutator may also invert to keep attraction force in the same direction
1 vote
Accepted

Tesla AC motor: question on component

the wires from the rotor windings enter the rectangular aperture on the hollow shaft and emerge at the end to feed the slip rings. The slip rings are used to get the AC electricity out Presumably this ...
• 26.7k
Accepted

Tesla AC motor: what is this component?

The 'stem' is a shaft $a^\prime$ that is being rotated by a prime mover (eg steam engine) off to the right of the diagram but not shown. The two rotating windings on the armature of the generator ...
• 29.2k

Tesla’s AC motor: questions on operation

Why would this disc rotate in the field? Why is the disc more efficient? The key here is to stop thinking about the motor as “pulling” the rotor using magnetic attraction - in fact an aluminum rotor ...
• 620

Non-regenerative braking on a PMSM/BLDC motor

I'm late, but the question is well asked, and I'm searching for a solution too. One of the items mentioned: Large Energy-Storage Capacitor These days apparently there are super capacitors e.g. https://...
1 vote

using LM3915 to switch relay or motor

Not exactly Rules of Thumb for Design BJT switches are optimized with about 10% of hFE max as a saturated switch coils will flyback back EMF voltage need some clamp protection V=LdI/dt. RC, R or R+...
1 vote

How can the energy produced by a generator be fed back to the motor that rotates the generator?

Whatever you do, you need something that meets all safety regulations in your locale. At this power level, you'll get very large sparks if something goes wrong, and a very upset insurance company if ...
• 140k

How can the energy produced by a generator be fed back to the motor that rotates the generator?

Just wire both ends to the mains in parallel. Assuming that your "Converter" is capable of synchronizing with the grid,you should already have all you need to reuse the generated power. Just ...
• 395
1 vote

How can the energy produced by a generator be fed back to the motor that rotates the generator?

It's easiest if your VFD has the ability operate off a shared DC bus. Then you can just feed into the DC inputs after making sure the voltage is at the correct level. It's way more complicated if your ...
• 46.4k

Problems of optimal commutation depending on number of pole

The problem you have with 2 pole pairs is that the construction of the rotor and the stator are such that for every North pulled by the stator there is a South which is, instead of 180° from that ...
• 9,692
1 vote
Accepted

Variable field magnet motor?

As this pictire form hyperphysic $\tau = ILWBsin(\alpha)$ And $E = \dot\theta WBL cos(\alpha)$ When we apply supply voltage actoss motor's terminal and current flow through armature coil as (...
• 952
1 vote

How does a system measure the speed of a servo motor using brushes on the commutator?

After some searching i figured out that this motor is combined with tachogenerator and it's output is 14v/1000rpm. Most probable causes at my opinion may be:  motor and tach terminals were ...
• 176
1 vote

Calculating AC Unit Watts

Using those calculations, you would only be able to estimate the average power drawn while the compressor is running. However, that is not too useful for the following reasons. The instantaneous ...
• 2,613

Vending machine motor: simple DC motor with microswitch, one revolution

Here's a simple circuit that uses a relay to drive the motor. Actuating the momentary push button switch energises the relay to start the motor. The push button may be released when the 'NC' contact ...
• 10k

Vending machine motor: simple DC motor with microswitch, one revolution

This is my interpretation of the circuit you have: simulate this circuit – Schematic created using CircuitLab Based on this it seems to me that the only way to get revolution feedback from this ...
• 13.2k

Motor voltage spike

The motor has considerable inductance (probably some ~mH), so its current cannot be set to zero instantly. An opposite voltage must be applied to cause the current to fall towards zero. This is ...
• 1,035

Is it possible to control a matrix of motors using H-bridges?

Yes it can be done. A patent was filed 1/2001 US6583591B2 owned by Yazaki doing almost the same thing. It has a good explanation that may help you. It uses a single 1/2 bridge for one side and several ...
• 2,553

Is it possible to control a matrix of motors using H-bridges?

I love this question! EDIT: finally sat down to think about this and it is not feasible as presented. Without diodes (like an LED matrix) current can flow through unselected motors (or really any ...
• 620

Vending machine motor: simple DC motor with microswitch, one revolution

A simple feedback mechanism is a normally-closed limit switch (SW1) in contact with a cam which is attached to the shaft of the motor or, more likely, the output of the gear train the motor is driving....
• 6,620
1 vote

Connecting two motors to one Arduino board

No. The buttons are wired incorrectly. They most likely won't do anything at all. You would need a pull down so that the "resting position" of the input is low. Your buttons could then ...
• 57.6k
1 vote

How can a reed switch be used for high current applications?

You will want a protection circuit (or BMS, stands for Battery Management System) for the LiPo pack, to implement overtemperature and overcurrent cutoff. The protection circuit will have a MOSFET that ...
• 4,680

How can a reed switch be used for high current applications?

For long-term reliability, a 60 A load requires relay contacts rated for at least 100 A. The coil current for such a contactor almost certainly is greater than the reed switch rating. There are at ...
• 12.6k

How can a reed switch be used for high current applications?

Don't use the reed switch directly. Use the reed switch to switch the coil of a larger relay. Alternatively, use the reed switch to switch the gate of a FET large enough to handle to load current.
• 57.6k
1 vote
Accepted

What does forward rotation of armature mean?

Looking from the shaft end, forward is clockwise and reverse anticlockwise.
• 10k
1 vote
Accepted

Why would a motor have 100kW in 90kW out?

This is simply about "pumped storage" hydroelectric. It's referring to limits and losses in the process. They might not be electrical. Remember during the pandemic when the cost of a barrel ...
1 vote

Why would a motor have 100kW in 90kW out?

From your information it is hard to say. So this is just a guess. It seems it was two different but somehow connected issues. Efficiency of a motor / generator 1 Motor or generator is never 100% ...
• 1,518
1 vote

Stepper motor doesn't move, just vibrates using DRV8428

There are 3 similar drivers : DRV8428 : Step/Dir interface DRV8428P: PWM DRV8428E: PH/EN In your schematics, DRV8428PPWPR is refering to DRV8428P. For STEP/DIR interaface, correct reference is ...
• 11

Using High Power Relays to Actuate an AC Motor

A motor is an inductive load. As the contacts open the inductor attempts to maintain current. Because of this the voltage momentarily increases. This effect causes arcing of the contacts. Arcing ...
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AC single-phase fan motor works (almost well) without start capacitor, but not with the correct capacitor connected?

The cable colour code, for connecting the motor, is as follows: Red - connection to line, through selector switch, for low speed Yellow - connection to line, through selector switch, for high speed ...
• 10k

bi-directional motor using SPDT relay and diodes

This is how I would do it: - It requires two change-over relay contacts operating in tandem. You might also wish to apply back-emf quenching diodes too. Here's another version of the same circuit (...
• 380k