Street Light Controller

Transcription

1 Street Light Controller

2 Table of Content Introduction:...3 Scope of the problem:...3 What we can do..?...3 The Device Light Controller:...4 Circuit Diagram:...4 Circuit Description:...5 PCB Layout design...5 Technical Details: Transistor BC Voltage Regulator:...6 Features:...6 Material list and Costing...7 Soldering and casing.8 Installation..9 Testing and results..10 References.11

3 Introduction: Electrical energy is very essential part of all human being. It is observed that, the demand for power is increasing day by day, but supply is not meeting to that demand and hence there is a huge gap in supply & demand. It is also observed that to meet the demand of industries, there is power cut in many non-industrial areas especially rural parts. Hence there is need to save the available power by proper usage of it. Scope of the problem: Generally it is observed that, there is less awareness about the usage of electricity. Many street lamps especially street lamps installed by government in urban & rural areas are not get turn OFF & turn ON at the right time and hence lots of power gets waste. For operating these kinds of lamps or outdoor lamps, one needs to take care of it & hence it includes delay as well as human resources. What we can do..? To overcome this problem we proposed a system called LDR based light controller which turns ON & turn OFF the lamp depending upon the light intensity. When light intensity decreases it turns ON the lamp & when light intensity increases it turns OFF the light. With this we can save the energy as well as human delay for operating the outdoor lamp.

4 A Device - Street Light Controller: Picture: Street light controller Circuit Diagram: Figure: Circuit diagram f Street light controller

5 Circuit Description: In above circuit diagram upper part is 5V power supply for LDR controlling circuit which is controlled through LM 7805 Voltage regulator. Here two resistors LDR and 10K potentiometer which is attached in between pin 5(GND) and pin 6 of connector externally forming a voltage divider circuit. When sun light falls on LDR, its resistance gets decreases and hence current starts passing through it which activates Q1 Transistor. At this state relay remained in Normally close state(nc). When there is darkness LDR value gets rise and that deactivates Transistor Q1. Current follows low resistance path and passing through R1 resistor which activates transistor Q2. Here at this stage Relay gets GND supply and it comes Normally open (NO) state which turns on street light connected to its NO end. Here diode D1 used for reverse current protection. Similarly when light falls on LDR relay takes NC position and street light turns off. We can control and adjust light intensity through 10 K potentiometer connected in at Pin 5 and 6 externally. PCB Layout Design: Designed this circuit inside EAGLE PCB design software. (Do not stretch /change dimensions of this file) Fig: PCB Layout

6 Technical Details: Components Used:- Transistor BC548 It s a plastic package general purpose NPN transistor which is commonly used for switching & amplification purpose. Features : Low current (max.100ma) Low voltage (max. 65V) Voltage Regulator: It is used to regulate the output voltage. It gives 5V DC constant voltage to the circuit. It can take input voltage up to 25V DC. Picture: Components

7 Material List and Costing: Components Quantity Rate (Rs) Price (Rs) Transistor BC Voltage Reg V Relay Transformer 9v/500mA Diode IN Resistor (1K) Capacitor 470uF K Variable Res LDR uF Capacitor Wires 1 (M) 10 7 Soldering Metal 60 (cm) 5 5 Enclosure 1 plastic box Connector Total 157 Note: All components are SMD (surface mount devices)

8 Soldering and Casing: Designed circuit diagram and created board file inside Eagle PCB design software. Printed this image file on ModellaMDX-20 to make PCB ready to solder. Make all components ready and solder it one by one. Picture : Soldering and assembling steps After making PCB ready with soldering fix it inside plastic casing with double sided tape. Put required holes on case for intensity adjustment and LDR sensor.

9 Installation: Connector connections: Load Supply Relay Connector Figure: Connection diagram To take connections outside from Relay and to give supply here I used white strip connector. Connections coming from NO and NC terminal of relay connected in 1st column. 230V supply given through 2 nd column to load and Transformer of power supply unit. Picture: Connector strip with connections

10 Testing and Results: For testing this unit is installed on Street light pole having Two tube-lights of load 80W. This works fine, average lights turn on at 7:05PM and turns off at 6:05 AM in summer days considering location India (Pune). Picture: Street light controller unit installed on 80W loaded pole Scope ahead: A few modifications can be done with the present system like:- 1. Better Casing or Enclosure for easy handling & tough weather condition. 2. Using contactor switch we can modify this circuit to handle maximum load

11 Propagation: We want this system should be adapted by the communities living in rural, urban & city areas to save the electric power. We also want the awareness about saving electricity should spread among all especially children s as they can save more electricity in their whole life. References: by -Suhas Labade. Technical Instructor, Vigyan ashram Fablab.