DOL motor starter operation

DOL motor starter operation

Application:-Make DOL starter logic in the PLC. Write PLC program for the DOL starter using ladder diagram language. 

Explanation:-

Generally in industry DOL starter is commonly used for motor control. In direct online starter, motor is controlled by start and stop button with fixed motor speed. In above diagram if start button is pressed, motor will be start by PLC and if stop button is pressed motor will be stop by PLC.

PLC program:-

Write the ladder program for above application using ladder diagram language. Here for ladder logic we can use any supported PLC system like S7-1200, S7-300, S7-1500 or any other PLC which can support this instruction. For PLC logic we need digital inputs and outputs.

For our application start and stop buttons are digital inputs and valves are the digital output. So define digital input address and output address as per below explanation,

Digital inputs:-

Motor start=I0.0

Motor stop=I0.1

Motor trip=I0.2

 

Digital Output:-

DOL Motor=Q0.0

PLC program Explanation:-

In network 1, we have used NO contact of motor start button (I0.0) and NC contact of motor stop and motor trip feedback, so when motor start button is pressed DOL motor will be start and if stop button is pressed, motor will be stop.