Making application to move block from the magazine feeder to conveyor using pneumatic system.

Making application to move block from the magazine feeder to conveyor using pneumatic system.

Problem Description: - There is one conveyor system. Single acting cylinder should start if user press bush button and block should move form magazine feeder to conveyor system for next process. 

Problem Diagram: -

Solution: -

Here we can consider single acting cylinder, take one spring return bush button to operate singly acting cylinder. Push button will work as 3/2 bush button valve. If bush button is pressed, cylinder will operate and move the block and if it is released, cylinder will back to its original position. 

Pneumatic circuit: - 

Pneumatic circuit explanation: -

Here we can see in the figure single acting cylinder with spring return. It can push block when required and it can come back with spring force if bush button released. Connect pneumatic pipe from A to cylinder in as shown in figure.

We took 3/2 bush button so in normal condition air will pass from A to R as shown in figure, so cylinder is in normal condition. If we press push button, air will pass from P to A so cylinder will move. Connect Main air line in Port P of the 3/2 push button.

If we release push button air will not pass from P to A so due to spring force it will come back.

 

Conveyors sequence operation

This is PLC Program for controlling conveyors ON sequence and OFF sequence.

 

Problem Description:-

There are three belt conveyor in the system. We need to control sequences of conveyors both ON sequence and OFF sequence. Implement logic in PLC using ladder diagram programming language.

 

Problem Diagram

 

Problem Solution.

We will use PLC S7-300 for this application. Also we will use TIA portal software for programming.

Conveyor belt 1 or conveyor belt 2 can be started by the corresponding START pushbuttons and can be stopped by corresponding STOP push buttons.

Conveyor belt 3 should always transport when either conveyor belt 1or conveyor belt 2 is transporting.

When OFF pushbutton is pressed, belt 1 or belt 2 is to continue running for 20 sec. and belt 3 for 60 seconds to clear the belts of material and Then stopped.      

 

There is 10 Hz. monitoring signal for belt status monitoring for all three belts. If there is fault in any one of the belts then the entire belt should turn off immediately.

 

 And OFF indications of previously running belts should flash with 5 HZ frequency.

 

Program

Here is PLC program for controlling conveyors ON sequence and OFF sequence.

List of inputs/outputs

List of inputs

System ON/OFF switch:-I2.0

Belt 1 START:-I0.0

Belt 1 STOP:-I0.1

Belt 2 START:-I0.2

Belt 2 STOP:-I0.3

Belt 1 fault:-I1.0

Belt 2 fault:-1.1

Belt 3 fault:-I1.2

List of outputs

Conveyor belt 1:-Q0.0

Conveyor belt 2:- Q0.1

Conveyor belt 3:-Q0.2

Belts running indication:-Q0.3

Fault indication:-Q0.4

Fan 3 ON Indication:- Q0.6

Main supply ON indication:-Q0.7

M memory:-

Cycle ON:-M0.0

5HZ clock pulse:-M0.5

10HZ clock pulse:-M1.0

 

Ladder diagram for controlling conveyors ON sequence and OFF sequence.

 

 

 

Program Description

For this application we used S7-300 PLC and TIA portal software for programming.

Network 1:-When system ON switch (I2.0) is pressed, cycle ON (M0.0) bit will be ON.

Network 2:-When belt 1 START PB (I0.0) is pressed, Conveyor belt 1(Q0.0) will be ON.

Network 3:- When conveyor belt 1 STOP button (I0.1) is pressed, timer will start to count time and after 20s timer will stop the conveyor belt 1 (Q0.0). If fault occur in conveyor belt 1, belt 1 should be STOP.

Network 4:-When belt 2 START PB (I0.2) is pressed, conveyor belt 2 (Q0.1) will be ON.

Network 5:- When conveyor belt 2 STOP button (I0.3) is pressed, timer will start to count time and after 20s timer will stop the conveyor belt 2 (Q0.1). If fault occur in conveyor belt 2, belt 2 should be STOP.

Network 6:-Either conveyor belt 1 (Q0.0) or conveyor belt 2 (Q0.1) is ON, Conveyor belt 3 (Q0.2) will be ON. If fault occur in conveyor belt 3, it should be STOP.

Network 6:-When both conveyors are OFF, Conveyor 3 off timer will be executed.

Network 7:-When conveyor belt 3 timer is executed, after 30s it will stop the conveyor belt 3 (Q0.2).

Network 8:-Either conveyor belt 1 STOP PB (I0.1) or conveyor belt 2 STOP PB (I0.3) is pressed, conveyor 1&2 reset timer will be executed.

Network 9:-If three conveyors are running in healthy condition, belts running indication lamp (Q0.3) blinks on 10HZ frequency.

Network 10:-If any conveyor belt is faulty out of three belts, fault indication lamp (Q0.7) will start to blink on 5HZ frequency.

Note:-Above application may be different from actual application. This example is only for explanation purpose only. We can implement this logic in other PLC also. This is the simple concept of conveyor ON and conveyor OFF sequence in industry, we can use this concept in other examples also.

All parameters considered in example are for explanation purpose only, parameters may be different in actual applications. Also all interlocks are not considered in the application.

 

Runtime Test Cases

Inputs	Outputs	Physical Elements
I2.0=1	M0.0=1,Q0.7=1	Cycle ON, main supply On indication lamp ON
I0.0=1	Q0.0=1	Conveyor belt 1 ON
I0.2=1	Q0.1=1	Conveyor belt 2 ON
Q0.0=1or Q0.1=1	Q0.2=1	Conveyor belt 3 ON
I1.0=1orI1.1=1orI1.2=1	Q0.4=1	Fault indication lamp ON