I have several small motors removed from toys and electronics. I would like to use these motors in the projects, but I do not know their voltages and currents. How to find them out?
Most small motors are specified for voltages between 6 and 12 V and the current is directly connected to their size, which will determine the torque. In most cases, the specified voltages are not exactly the voltage with which they should work. Thus, a 6 V motor will work well at voltages from 3 to 9 V without problems. This way, even without knowing the exact voltage of one of these motor, you can try it with 6 V and observe if it works well, without heating and giving a reasonable torque. If it warms up it is because it is an engine that is recommended to operate at 3 V or 4.5 V and if it is not very strong, try connecting at 12 V.