What is Magnetic Contactor?We can also said that a contactor is type of electrical relay which we use for power electric motor to start or stop. Contactor make easy to controlled 3 phase induction motors. We know that 3 phase motor required three phase supply to run, 3 phase supply is two dangerous which we can not handle with a circuit breakers for induction motor. Contactor make easy to handle the 3 phase motor controlling. The parts of the magnetic contactor are coil, iron core, 3 contacts points and NC, NO points.
How a Magnetic contacor WorksThe function of a contactor or motor starter is simple, when the AC supply goes to the contactor coil, the coil make a strong magnetic field and field pulls the iron core to the coil and make a electrical contacts.
What are NC, NO in Contactor
The NC means the Normally close electric circuit or we can said it is a normally close contacts and NO meas normally open contacts. In normal state when contactor coil does not energize the NC point is normal close state and when the coil energized these these NC contacts create a NO contacts between one another, after coil deenergized NC contacts make a close circuit.
Same the NO contacts change on coil energizing to the NC contacts.
Advantages of ContactorThere are many advantages of 3 phase contactor but some are very important which are below.
You can controlled power motors easily by pushing a small button.
You can ON/OFF electrical 3 phase motor in small time.
You can safe him self for electric shock in 3 phase motor starting.