POLYHOUSE AUTOMATION USING PLC

POLYHOUSE AUTOMATION

Presented ByMahendra MagreRitesh JadhavSamadhan Parsewar

INTRODUCTION

• What is POLYHOUSE ???• 3 “P” s – Protective– Productive– Profitable

• Objective of the Project

INTRODUCTION (continued….)

Need for Automation• Automatic Control• Reduces Human Error• Minimizes labor cost• Manages unwanted environmental conditions• Increases productivity

SYSTEM DESIGN

PLC

Crop Selection

Panel

Monitoring SystemSensors

Polyhouse Monitoring System

SYSTEM IMPLEMENTATION

Selection Panel :• Consists of LED indicators and Toggle switches Programmable Logic Controller :• Allen Bradley Micrologix 1200C• Specifications-8 DI & DO,2 AI & AO• Sensors• Soil Moisture sensor :- Soil moisture circuit• Temperature Sensor:- Thermistor• Light Intensity:- LDR

DESIGN OF SENSORS

1) Temperature sensor: - • Required range: 25 C to 50 C ⁰ ⁰• Thermistor is used in

Wheatstone bridge for signal conditioning.

2) Light Intensity Sensor: - •LDR is used •Wheatstone bridge •Instrumentation amplifier circuit for amplification

3) Soil Moisture Sensor:-– Moisture content of soil is determined– Two conductive plates are used– Relative humidity of 60 – 80 % required

FLOW CHART

PROCESS CONTROL

Programmable Logic Controller

Programmable device

CPUInputModule

Memory

Power Supply

OutputModule

SensorsLimit s/wPress. s/wEtc.

Control valves,Motor StarterEtc.

TYPES OF PLCs :1) Fixed Plc2) Modular Plc

Programming Languages in PLCs :Ladder Logic ( LAD/LD ) Structured Text ( ST) Instruction List ( IL ) Sequential Function Chart ( SFC ) Function Block Diagram ( FBD )

PROGRAMMING OF PLC

1) Ladder Diagram: • electrical sequences of operations. • represent the interconnection of field

devices OnOff

acc. to predetermined sequence of events• Purpose - represent hardwired logic

circuits

• If it is < set point, then one output will be done.

2) Steps Description:• Mov Analog input to N7.• Compare this value with the set point

integer value stored in register• two actions according to the comparison.

• If it is > set point, then other output will be done.

• The above 3 steps will occur simultaneously for three input sensors.

• Crop selection is done using the toggle switch.• The toggle switch which is currently selected will

complete the specific rung

REFERENCES

• “Programmable Logic Controllers” by V.R.Jadhav.• “Process Control Instrumentation Technology”, Johnson C.

D., 7th edition, Pearson Education, New Delhi, 2003.• Ramakant A. Gayakwad, “Op-Amps and Linear Integrated

Circuits”, Publisher PHI prentice hall India, Fourth Edition, 543, Page no.438,439.

• “Sensors and Transducer”,B.C.Nakra& K.K.Chaudhry.• http://www.aces.edu/pubs/docs/A/ANR-1144/index2.tmpl• http://www.haifa-group.com/files/Guides/tomato/

Tomato.pdf• http://www.nr.gov.nl.ca/nr/agrifoods/crops/veg_pdfs/

spinach.pdf

Thank you ….!

• Any Questions……?