Reversing the Direction of Rotation in a Split-Phase Induction Motor
How can the direction of rotation of a split-phase induction motor be reversed?
What is the dual-voltage rating of a split-phase induction motor and how is it connected for 230-volt operation?
Reversing the Direction of Rotation
To reverse the direction of rotation in a split-phase induction motor, the connections of the starting or running windings can be reversed. In a 230-volt operation, the two running windings are connected in parallel to the power source, while the starting winding is connected in series with a capacitor. A starting capacitor is used to reduce the initial current draw when the motor is turned on.
A split-phase induction motor can reverse its direction of rotation by either reversing the connections of the starting winding or reversing the connections of one of the running windings. When the connections of the starting winding are reversed, the phase angle between the two windings is also reversed, resulting in a reverse rotation.
For a split-phase induction motor connected for a 230-volt operation, the schematic diagram would show the two running windings connected in parallel to the 230-volt source, and the starting winding connected in series with a capacitor to the 230-volt source.
To avoid a large initial current when the motor is turned on, a starting capacitor is used in conjunction with the starting winding. The capacitor creates a phase shift and allows the motor to start with a reduced current.