Magnetic Motor Contactor
Magnetic motor contactors are the mediators between high-load electrical motors and direct power sources. These magnetic contactors are electrically controlled switches found on most electrically powered motors.
Although magnetic contactors are similar in design to circuit breakers, they perform very different functions. Instead of breaking the connection between a power source and appliance during a short circuit, they can be detached from a motor so an operator may disassemble or maintain that motor.
Magnetic motor contactors are essential because they act as a safeguard and balance changes in electrical frequency that may come from a power supply.
What Is a Magnetic Motor Contactor in a Motor?
A magnetic motor contactor in a motor works in tandem with an overload relay to operate a magnetic starter safely and effectively. Magnetic contactors have electromagnets that allow them to disengage if the power to the machine should fail.
They can be assembled with disconnecting means, overload relays, short-circuit protection and an enclosure to form a combination starter. These combination starters — grouped with other control devices and switchgear — can be assembled in a common enclosure called a motor control center.
What’s the Purpose of a Magnetic Motor Starter?
It’s important to understand a magnetic starter’s role in order to discuss the function of a magnetic motor contactor in a motor. Magnetic starters consist of an overload relay and an electrical contactor, which work together to protect an engine in case of a power outage. The overload relay will open the control voltage to the motor’s started coil if it catches an overload.
Using these two components, a magnetic motor starter is able to stop and start a connected motor safely. Magnetic motor starters also provide an automatic cutoff — as well as overload and under-voltage protection — in the event of a power failure.
What’s the Difference Between a Magnetic Motor Starter and Contactor?
The main difference between a magnetic motor starter and a contactor comes down to the ability to provide overload protection for a motor. A motor starter supplies overload protection — a magnetic motor contactor does not. Although the two terms are often used interchangeably, they are quite different. A magnetic motor starter is made up of both a contactor and an overload relay, while a magnetic motor contactor stands on its own.
A magnetic motor starter is just a contactor with an overload relay — the relay’s purpose being to drop out the coil voltage if the motor overloads to prevent overheating.
Contact Global Electronic Services Today
A great way to remember the difference between a magnetic motor contactor and a starter is to picture the motor starter as the complete assembly. This includes the contactor and enclosure, as well as the overloads, fuses and a control transformer, if any.
Your business can count on Global Electronic Services for all your servo motor, industrial electronic, pneumatic, AC and DC motor and hydraulic needs. If you need help selecting the right magnetic motor starter or contactor for your specific application, feel free to reach out to our team today.
