Automatic Street Light control using ARM

Automatic Street Light control using ARM

Power is a non-renewable source which has to be conserved and utilized in an efficient way. Most of the time we observe that street lights has to turned on by someone during night  and it has to be turned off  on the following morning. If he forgets to turn them off Street lights will run even during day time which leads to huge power loss. This problem can be well addressed by this project.

Considering above mentioned aspects Automation in turning on/off of street lights can be done by using sensors like LDR, IR etc

1. Street Light has to be turned on automatically when it goes dark 

2. Only if someone comes in that vicinity it has to be turned on.

3. Street Light has to be turned off automatically when no one in that vicinity, when surrounding  visibility is good.  

    

LDR , IR can be used in conjunction to solve it.

Analog Input can be taken from A in

when Light falls on LDR- it offers low resistance of (10 -50 ohms) ideally zero so there will be low voltage drop across LDR. 

when no light falls on LDR it offers high Impedance of (10M ohms) ideally infinite impedance so it acts like open circuit and entire voltage appears across LDR.

IR - LDR can be used together(Logical AND) to control street light

For demo i used only LDR
Observer Led it will be off when External light is ON when light falls on LDR
Led will turrn on when External Light is OFF.

code- Download