Contactor

Q1. What is a contactor?

A contactor is an electrically controlled switching device used to control power circuits. It is commonly used to switch motors, lighting, heating, and other heavy loads.

Q2. How does a contactor work?

HMI are commonly used in manufacturing plants, automation systems, packaging machines, energy management, water treatment plants, and building automation.

Q3. What are auxiliary contacts used for?

Auxiliary contacts are used in control circuits (signal indication, interlocking, feedback) and cannot handle large currents like main contacts.

Q4. What are the main parts of a contactor?

Coil (Electromagnet) – energizes to create magnetic field.

Contacts (Main & Auxiliary) – carry and switch current.

Frame/Enclosure – holds all parts and provides insulation.

Q4. What are the types of contactors?

AC contactor – used in AC circuits (motors, compressors, pumps).

DC contactor – used in DC circuits (battery systems, EVs).

Mini contactor – compact, for small loads.

Capacitor contactor – specially designed for capacitor switching.

Q6. How do I select the right contactor?

Rated voltage (coil voltage & load voltage)

Current carrying capacity (in Amps)

Type of load (motor, lighting, capacitor)

Duty cycle (AC1, AC3, AC4 ratings)

Number of poles and auxiliary contacts