The squirrel cage rotor motor has a rotor made of copper or aluminum rods installed in the grooves of the rotor, where the ends are joined by a copper or aluminum ring. Between the iron core and the winding of bars there is no need for insulation since the induced voltages in the rotor bars are very small. This type of engine has the following characteristics:
– Speed ranging from 3 to 5% vacuum to full load;
– Absence of speed control;
– Possibility of having two or more fixed speeds;
– Low or medium starting capacity, depending on the type of squirrel cage rotor.
These motors 3/4 horsepower 56c frame are used in situations that do not require variable speed and can start with load and because of this are used in mills, fans, presses and centrifugal pumps. In the operation of the electric motor with a squirrel cage rotor, the rotor, formed by copper conductors, is subjected to the rotating magnetic field, previously shown, and as a consequence, these conductors (squirrel cage bars) circulate induced currents due to movement of the magnetic field.