Starters and contactors are used in a wide range of applications of lighting, motor control, conveyor, and pumping type programs. Providing great flexibility for AC and DC control, they are typically used in material handling equipment, machine tools, compressors, demanding automotive applications, and more.
The starters and contactors available in the market are manufactured with the ability to withstand the hazardous and severe conditions of industrial and commercial markets. Most manufacturers also produce various types of add-on accessories and spare parts to help the main products offering more adaptability for different systems.
What Is a Motor Starter?
An electric motor starter does the job of switching on and off a motor besides protecting the motor system from overload and phase failure in any industrial application. The AC motor starters do the function of combining a magnetic contactor and an overload relay.
What Is a Motor Contactor?
An electrical motor contactor is an electrically controlled switch that mainly performs the function of switching on and off a power circuit. Using it to control a power circuit is safe, and the advanced models are user-friendly and cost-effective too. Their function is almost similar to relays except for they work with higher current ratings. However, they don’t interrupt a short-circuit current unlike circuit breakers.
Contactors are available in many sizes with varying features and capacity ranges. They are mainly used to control lighting, electric motors, capacitor banks, heating, and other systems.
Starters and Contactors: Common Types
Some starters and contactors that are most familiar in various industrial applications are given below:
They are a simple type of starters that do the functions of controlling the on/off switch and providing overload protection to motors.
Two mechanically interlocked magnetic contactors along with an integrated thermal overload relay go into the making of such a starter. They do the job of start/stop in forward and reverse rotation in a motor system. The integrated relay protects the motor against overload conditions.
Starters with Special Thermal Overload Relays
Such starters provide protection to motors that have a low heat capacity or a long startup time.
Such contactors allow direct control of three-phase motors. They are also capable of controlling resistive loads in lighting and heating applications.
Mainly used for start/stop functions, these contactors are also flexible to be used for reversing AC motors in applications where the motors don’t require protection against overload conditions.
Solid State Contactors
The contactors are used in applications where it is required to control the power at low noise levels. They are mainly used in lighting systems and temperature controllers.