What is DOL starter in PLC?

1) DOL Starter DOL stands for Direct Online Starter, most commonly used in the industry to start the motor. In this method, full voltage is applied to the motor, but the starting current would be very high(usually 5-8 times more than it’s rated current).

How does a PLC start a motor?

A PLC has to start a Motor when the Start button is pressed. It has three interlocks which are Motor Vibration High, Overload & Motor Temperature High. if any of the interlock activated then PLC has to stop the motor immediately. PLC has to stop the motor if the stop button is pressed.

What is PLC motor control?

The programmable logic controller (PLC) is probably the most widely-used controller in automation and manufacturing applications. It was originally designed to mimic electrical circuits, replacing the switches and relays that controlled machine motions, for reduced wiring cost and complexity.

What is DOL motor control?

A direct on line (DOL) or across the line starter applies the full line voltage to the motor terminals. This is the simplest type of motor starter. A DOL motor starter often contains protection devices (see below), and in some cases, condition monitoring.

What are the types of DOL starter?

There are 5 types of starters are used to start electrical such as

• DOL – Direct online starter – Motor range below 10 HP. Stator resistance starter-
• Star- Delta starter – above 10 HP Motor.
• Autotransformer starter – above 1 HP.
• Soft starter – motor range above 150 HP.
• VFD – Any range of motor.

Why is DOL starter used up 5 hp?

For a large rating motor, ranging from 5 HP to 25 HP, oil immersed DOL starters are used which provides insulation against sparking on contact points and hence increases the life of starter. DOL starter consists of MCCB, contactor, and overload relay.

How does a DOL motor starter work?

In a DOL Starter, an induction motor is connected directly across its 3-phase supply, and the DOL starter applies the full line voltage to the motor terminals. Despite this direct connection, no harm is done to the motor. A DOL motor starter contains protection devices, and in some cases, condition monitoring.

What is the wiring diagram for a direct online starter?

DOL Starter Wiring Diagram The wiring diagram for a DOL stater is shown below. A direct online starter consists of two buttons, a GREEN button for starting and a RED for stopping purpose of the motor. The DOL starter comprises an MCCB or circuit breaker, contactor and an overload relay for protection.

What is direct on line (DOL) starter?

The Direct On Line starter is the simplest form of motor starter. The direct online starter is a basic and simple starter used for starting the induction motor. In DOL Starter, we connect the stator winding of the induction motor directly to three phase supply voltage. Thus, the stator winding receives full line voltage.

What is a direct on line motor starter used for?

Still commonly used in many factories the DOL or direct on line motor starter is another way of starting AC motors. The DOL is made of a contactor (usually 3-phase contactor), an overload relay like the thermal relay, and some connections in between.