Understanding plc ladder logic programming example
This article is an example of what a rung of a ladder logic program would look like. In real life, there may be hundreds or thousands of steps.
For beginner who will be develop your PLC program ,if you are understand this concept that you can develop more PLC program in next time.
For example,
1.
The above function is to be conscious with equation: S = X * (Y + Z)
Typical complex ladder logic is ‘read’ left to right and from top to bottom. Since each of the lines) is (or stages Nominal coil is a step in the next phase of the conductors are taken as input. In a complex system, it is numbered many “steps” on a ladder, in order of their rating.
2.
2. T = S * X, where S corresponds to # 1 on
This is a slightly more complicated system of the 2nd Level After the first line has been surveyed, the output coil (S) in Step 2, which is then evaluated and the outcome of T-coil could be added to an output device (buzzer, light, etc.). Or is integrated in step 3 on the ladder.
This system allows a very complex logic patterns must be broken down and evaluated.
Other practical examples, see below:
Shows these logic diagram the two most important parameters that security forces can use to activate the motor in a bank vault door. When the normally open contacts close the two switches, current will flow in a position to the motor that opens the door. This is a logical AND.
This ladder diagram shows the two things that cause power door locks in my imaginary car. The remote receiver is always powered. Lock Solenoid have power, if any of these contacts are closed. This is a logical OR.
Often we have to drive a small green button “Start” to a motor, and we want to turn it off with a big red “Stop” button.
