Motor control have a two basic methods.There is MANUAL control and MAGNETIC control.I describe detail about manual and magnetic control circuit diagram and basic operation.
Motor control definition
1) Manual Motor Control
When first motor were introduced for application,the common control is only basic manual stop and start circuit diagram.
It only have a main switch for stop start operation and fuse for motor protection.This method have disadvantage and not safe to used because as shown circuit diagram below :-
1) Motor operation always done by manually by operator.It not practical and can defected by human error.
2) Not safety when switch the bigger size of electric motor due to high in rush current and must more physical effort to switched.
3) It can be dangerous and can cause accidents due to sudden restarting of motors after power supply restoration.
2) Magnetic Motor Control
This method is common application now due to flexibility,easy to handling and more safety device to protected motor for damage.It used two important component that we call CONTACTOR and RELAY.
With this magnetic component,we can energized a main contact only with small power.It gave more desire to control of machine or equipment.We can control with various operation depend on our application such as stopping,starting,rotation and speed variation.Circuit diagram for magnetic control as shown below :-
3) Advantage of Magnetic Control
1) Provide safety to the user when operated the motor and reduce risk to accidental contact with live conductor or exposed to power arc and flash.
2) No need additional skills to operated the system because it user-friendly.
3) Can reduce breakdown,wear of component and more life span of motor due to we can control a high in rush current and peak.
4) We can design the control with interlocking system for various operation of multi motor drive and can running in automatic sequence for safety purpose.
5) Can integrated with new technology of controlling device such as PLC,DSC,VFD and many more.It make more efficient and easy to operated.