I want to know what type of motor this is. It has brushes, 2 coils, 1 electromagnet, and 1 commutator of copper in the middle. I have a lot of doubts because I'm learning.

  • Is this a universal motor or an AC motor with brushes?

  • I have concluded that the brushes have 2 different polarities, which will create a magnetic field on the electromagnet, but how does it move? Does the magnetic field of the electromagnet collide with another magnet there?

  • Does it have a fixed magnet?

  • What is that yellow thing? Is it a capacitor?

  • If the same system, with the same coils, would experience a current of 220 volts instead of 110 volts, would it create more power? I mean, does more intensity of current creates a more intense magnetic field, and so, more power?

    look at that yellow box, that's what I've talked about enter image description here

  • \$\begingroup\$ Don't run this motor unloaded for prolonged time because its speed can go very very high if unloaded. \$\endgroup\$ Sep 11, 2016 at 6:21
  • \$\begingroup\$ An easy test for a universal motor, is to apply a modest DC power source, and observe which direction the motor turns. Then reverse the DC polarity; if the motor turns the same direction, it is a universal motor. \$\endgroup\$
    – Whit3rd
    Sep 12, 2016 at 6:51

1 Answer 1


The motor is most likely a universal motor. A universal motor is DC motor with the armature and field windings connected in series with each other. It can operate with either AC or DC because the armature current is always flowing in the same direction as the field current. Since the same current flows in both coils, the alternating current reverses at the same instant in each coil.

The picture does not show enough detail to allow identification of the yellow thing. There are several possibilities.

If the voltage is increased, the motor speed will increase, but the torque capability will stay the same. That will increase the power because power is speed multiplied by torque. Of course, the driven load will also effect the power delivered.

You should visit some tutorial web sites to get a more detailed explanation. This site is intended for specific questions that have specific answers. Detailed explanations of how things work are difficult to handle in this format.


If the motor is designed for 110 volts and 220 volts is applied the motor would likely fail quite quickly due to excessive speed, or overheating. It could possibly break apart sending parts flying. Overheating could possibly start a fire. As mentioned in the comment by soosai steven, even running the motor without a load could cause the motor to operate at a dangerously high speed.


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