Forward & Reverse Direction of Induction Motor and DC Motor:
Forward & Reverse of three phase Induction motor:
Induction motor are categorized by two types, one is single phase induction motor and another one is three phase induction motor. In case of three phase induction motor, they are self-started motor and the motor direction would be the direction of rotating magnetic field. For reversing the motor direction, we have to change the direction of rotating magnetic field. This is implemented by changing the supply phase sequence of the motor.
Example: You have a motor (motor terminal U, V, W) which is connected with the phase sequence (Supply phase R, Y, B) of R-U, Y-V, B-W in a forward direction. To reverse the motor, you have to connect the motor and supply phase in such a condition. R-V, Y-U, B-W.
Forward & reverse of single phase induction motor.
Single phase motor consists of two winding such as main winding and auxiliary winding. They are not self-starting motor, because of they do not have rotating magnetic field such as three phase induction motors. Normally, for starting of single phase motor we use capacitors. The main power supply would be directly connected with the main winding and Capacitor is connected in series with the auxiliary winding and supply phase. Here capacitor is used to create the phase shift from existing phase. Hence the motor gets two phase and it starts rotating. Here we can change the motor direction by changing the capacitor connection. The capacitor can be connected in series with the main winding instead of auxiliary winding.
Forward & Reverse of DC motor:
DC motors are totally different from AC motors. They have commutator, field winding and armature winding. The DC supply will be given to the field winding and armature winding. You can reverse the direction for DC motor in two ways. They are……
- By changing the supply Polarity in field winding or filed supply. Field terminal consist of F1 and F2. Normally, in forward direction the DC supply will be given such as F1 – Positive and F2 – Negative, to change the direction the polarity should be F1- Negative and F2 – Positive.
- Also in same way we can change the direction of DC Motor by changing the polarity of the armature winding. Armature terminal consist of A1 and A2. Normally, for forward direction the DC supply will be given such as A1 – Positive and A2 – Negative, to change the direction the polarity should be A1- Negative and A2 – Positive.