HOW TO START A DO-IT-YOURSELF STEPPER MOTOR WITHOUT ELECTRONICS

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I have a lot of different office equipment that is out of order. I do not dare to throw it away, and suddenly it will come in handy. From its parts, it is possible to make something useful.
For example: a stepper motor, which is so widespread, is usually used by DIYs as a mini generator for a flashlight or something else. But I almost never saw that it was used precisely as an engine for converting electrical energy into mechanical energy. It is understandable: to control a stepper motor, electronics are needed. You just can’t connect it to voltage.
And as it turned out - I was wrong. A stepper motor from a printer or from some other device is quite simple to start from AC.
I took such an engine.

Usually they have four leads, two windings. In most cases, but there are others of course. I will consider the most running.

Stepper motor circuit

Its winding circuit looks something like this:

Very similar to a conventional induction motor circuit.
To start you will need:

Capacitor with a capacity of 470-3300 uF.
AC power 12 V.

We close the windings in series.

Twist the middle of the wires and seal.

We connect the capacitor with one output to the middle of the windings, and the second output in the power source to any output. In fact, the capacitor will be parallel to one of the windings.

We supply power and the engine starts to spin.

If you transfer the output of the capacitor from one power output to another, then the motor shaft will begin to rotate in the other direction.

Everything is extremely simple. And the principle of operation of all this is very simple: the capacitor forms a phase shift on one of the windings, as a result of the windings they work almost alternately and the stepper motor spins.
It is very unfortunate that the engine speed cannot be regulated. An increase or decrease in the supply voltage will not lead to anything, since the speed is set by the frequency of the network.
I would like to add that in this example a DC capacitor is used, which is not quite the right option. And if you decide to use such a switching circuit, take an AC capacitor. You can also do it yourself by turning on two DC capacitors in an in-series fashion.