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9

I suggest using a separate board for the controller. Why? It's only two more wires. Your students will learn the difference between a motor and controller. Easier to debug and repair. Motor can have longer wires without worrying about ground loops etc. Possibility of using a different motor, or some other device.


8

If it's an output power rating, it won't be at full speed (which is the unloaded speed) but at rated speed, which varies, but will typically be 80-90% of the unloaded speed. Decent motors will specify the measurement conditions and show how speed reduces as power increases for a given voltage under increasing load (torque) and current.


5

A properly specified BLDC motor (or in fact any motor) will state its mechanical output power. If the motor specification says 500 watts (and it's a reliable specification) then that is the output shaft power. Input power can be a little to a lot more depending on how you drive it and what you are asking the motor to do regards speed and torque.


5

Polulu sales blurb: Continuous rotation servos are standard hobby RC servos that have been modified to offer open-loop speed control instead of their usual closed-loop position control. The modification effectively turns them into motors with integrated motor drivers in a compact, inexpensive package. Just throw on a wheel and you have a drive system for ...


4

From this question you can see the typical schematic of a two-speed inexpensive hair dryer. The heater forms a voltage divider to feed the low voltage DC motor (via a bridge rectifier), and you can switch an additional rectifier in series for 'low'. The fuse (FU = 熔断器) and thermostat (ST = 恆溫器) are for obvious safety reasons. If the air flow is obstructed ...


2

Definitely just marketing jargon to mean "powerful". Sort of like how Tesla calls its high-power charging stations "superchargers". As you said, it's definitely nothing to do with a turbocharger on an internal combustion engine. There's no similar concept for electric motors. Simply higher current in --> higher torque out.


2

Mechanical losses are bearing friction and aerodynamic drag. Those losses are not influenced by voltage. Power lost to bearing friction is directly proportional to speed because the torque loss is not much influenced by speed, but power is torque multiplied by speed. Power lost to aerodynamic drag is proportional to the cube of speed because is is like the ...


1

I think your reverse engineering is in error. C101 and R103 would be a snubber directly across MT1 and MT2 and usually shown to the right of the triac. R102 would usually be connected directly to MT1. Figure 1. A typical opto-isolated circuit. Image unattributed on Triac Switching circuit with Optocoupler Should I be getting 0V across the motor when the ...


1

An automotive wiper motor will require 12 volts - your two AA cells only provide 3 volts - probably not enough to move the motor. Also, the motor probably requires around 3 Amps - far too much for AA cells, even if you had enough AA cells in series to make 12 volts. Eight C or D cells in series would probably work, but a 12 volt lead-acid or gell-cell ...


1

If you'd take time to read a bit more through the datasheet, you'll find that two pages below, in the Current Sense Amplifiers section, this text appears: The DRV8305 provides three bidirectional low-side current shunt amplifiers. These can be used to sense the current flowing through each half-bridge. If individual half-bridge sensing is not required, a ...


1

It will run fine, but will not be capable of its full 220V speed It is common practice to speed-limit fan motors by reducing the supply voltage. They don't see increased current because the torque drops off faster than the speed.


1

simulate this circuit – Schematic created using CircuitLab Figure 1. Two options. The diodes sketched in your diagram will work. Figure 1a shows them drawn a little more clearly. Whichever way the motor is running the current will be diverted to the power supply - if it can take it. Figure 1b uses two Zener diodes back-to-back to allow for forward and ...


1

Answer to Q1: B or C, NOT both. you will burn the motor out. ,, ,, Q2: Both wires are connected to the capacitor. You just swap the supply lead from one to the other. I knew that type of motor as a 2 phase motor. There are 2 identical windings inside phased at 90 degrees. One connected to the blue wire, and the other to the red. The black is the common. ...


1

This can't be answered based on the information you have provided. It depends on what force is resisting the movement. One very strong person can pull a train, slowly. The train is very heavy, but there's nothing actually holding it back. But they couldn't pull a car with the brakes on because the brakes are on. It also depends how strong the motor is. There ...


1

With a brushed DC motor, it's relatively easy. One way to express it is that you measure the resistance of the motor, and calculate the stall current. However, as the resistance of brushes varies somewhat with current, you need the resistance at the stall current, so to get that accurately, you end up measuring the stall current anyway. But however you do it,...


1

Mechanical output power is determined by torque and speed. Speed is limited by supply voltage and how much the bearings of the motor are rated for. Torque is limited by how much current the motor coils can take without overheating, which is mostly constant irrespective of speed. Thus the actual motor power will depend a lot on the actual application: what ...


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