Conveyor Sorting System Schneider M340 PLC

In modern industrial manufacturing, automatic sorting of products is a critical requirement. A Conveyor Sorting System is used to separate different types of products on a conveyor belt and direct them to their respective output lanes without any manual effort. This system uses proximity sensors, pneumatic pushers (sorters), a conveyor motor, and a Programmable Logic Controller (PLC) to identify and sort products automatically. In this assignment, the Conveyor Sorting System is designed to sort three types of products: Plastic Bottles, Aluminium Cans, and Steel Cans. The animation was designed to simulate real-life operation using counter values for product position tracking.

SYSTEM OVERVIEW: -

The Conveyor Sorting System consists of one main conveyor belt and three separate output lanes, one for each product type. The three products handled by the system are:

1. Plastic Bottle

2. Aluminium Can

3. Steel Can

Each product has its own dedicated pneumatic sorter (salter), sensors, counters, and indicator in the PLC program. The operator selects the product type by pressing the corresponding button on the control panel. Once selected, the product appears on the conveyor and moves toward its designated sorting lane.

COMPONENTS USED: -

Programmable Logic Controller (PLC)

Control Panel / Operator Interface

Conveyor Belt Motor

Pneumatic Sorter / Salter (3 units - one per product)

Proximity Sensors (Sensor0 and Sensor1 for each product)

CTU (Count Up) and CTUD (Count Up-Down) Counters

TON Timer

Push Buttons: MAIN_START and MAIN_STOP

Product Selection Buttons: Plastic_Bottle, Aluminium_Can, Steel_Can

WORKING: -

When the MAIN_START button is pressed, the system becomes active and the main indication light turns ON. The operator then selects the product type by pressing one of the three product buttons on the control panel.

Once a product is selected, the corresponding product animation appears on the conveyor belt. The PLC uses CTU counter values to track the horizontal and vertical position of the product on the conveyor. As the counter value increases, the product moves forward on the belt toward its assigned sorting station.

When the product reaches the sorting position, the virtual Sensor0 detects the product, and the salter (pneumatic pusher) begins to move downward. Sensor1 confirms the product position, and the salter pushes the product off the main conveyor into the correct output lane box. The CTUD counter values control the up and down movement of the salter.

After sorting, the product counter for that lane increases by one, the salter retracts upward, and the system resets for the next product cycle. The MAIN_STOP button can be pressed at any time to stop all operations immediately.

HMI SCREEN VIEWS: -

Fig. 1: Conveyor Sorting System - Initial State

 

Fig. 2: Conveyor Sorting System - Sorter Activated

 

Fig. 3: Conveyor Sorting System - Product Sorted

 

PLC LOGIC DESCRIPTION: -

The PLC logic for this system is divided into separate sections for each product. The key logic elements used are:

CTU (Count Up) Counters: Used to count the horizontal (Ho) and vertical (Vo) movement of the product on the conveyor. When the horizontal counter value reaches the preset value, the product is considered to have reached the sorting station.

CTUD (Count Up-Down) Counter: Used to control the salter position. The salter counts up to move down and counts down to retract upward. This simulates the pneumatic cylinder extend and retract operation.

TON Timer: A 0.5 second ON-delay timer (TON_1) is used to control the speed of the conveyor animation and product movement cycle.

Virtual Sensors (Sensor0 and Sensor1): These are not physical sensors but are simulated using comparison instructions (EQ and GE) applied to counter values. Sensor0 triggers when the horizontal count equals 6, and Sensor1 triggers when the vertical count equals 3, to replicate sensor detection logic.

Product Counter (CTU): After the sorting is complete, a separate counter records the total number of products sorted into each output lane.

PLC LOGIC:-

CONCLUSION: -

The Conveyor Sorting System demonstrates the practical application of PLC programming in industrial automation. The use of counter values to simulate product movement and sensor detection is an innovative approach that allows realistic operation without physical hardware. The system successfully sorts three different product types, Plastic Bottles, Aluminium Cans, and Steel Cans, into separate output lanes using pneumatic sorters controlled by PLC logic. This project helped in understanding the use of CTU, CTUD counters, TON timers, and comparison instructions in real-life automation scenarios.

 By Vicky