In the year 1997, the electronic eye security system was found and base of processes in New Delhi. There are different organizations under these systems,such as electronic eye Pvt.Ltd, IIST (Indian institute of science and technology), electronic eye systems, and Mahamahi Exims. The electronic eye security system creates an entire collection of surveillance products and high-tech security. These Systems work on the integration of system and project execution at the customers place for numerous surveillance products.The electronic eye security systems which are available in the market are expensive, and programming is very problematic for a microcontroller based system. Here is a simple and inexpensive electronic eye security system that you can build easily.
Photo-sensing (LM393) based Electronic Eye Security System
The main goal of this project is to design an electronic security system based on a photo-sensing arrangement. It uses a double comparator LM393 that is extensively used in several profitable applications. Here, it is used to detect the input signal through a LDR (light-dependent resistor). The output of the comparator drives a relay and a buzzer. This concept is very beneficial as a burglar warning in public places such as banks, hotels jewelry stores, malls, and homes.
What is LM393?
The LM393 is a dual independent precision voltage comparator accomplished by single or split supply process. These devices are intended to let a common mode range-to-ground level with the only supply operation. Input offset voltage conditions as low as 2.0 mV make this device a superb collection of several applications in buyer automotive and industrial electronics. The features of LM393 include the following.
- Single supply ranges from 2.0 Vdc to 36 Vdc
- Split Supply Range: +/-1.0 Vdc to +/-18 Vdc
- Low Current Drain Independent of Supply Voltage: 0.4 mA
- Low i/p Bias Current is 25 nA
- Low i/p Offset Current: 5.0 nA
- Power Supply Voltage and differential i/p voltage range both are equal
- O/p voltage is compatible with ECL, DTL, MOS, TTL, and CMOS Logic Levels
- ESD locks on the i/ps
- ESD Locks on the i/ps increase the roughness of the device without disturbing performance
Circuit and Working of the Electronic Eye Security System
The circuit diagram of an electronic eye security system using LM393 is shown below. The following circuit is built with various electrical and electronic components like around 12V-0-12V, X1-(750mA secondary transformer), 1N4007 rectifier diodes (D1 through D3), LDR , C1 and C2 filter capacitors, 5V IC17805 voltage regulator, IC2 (dual comparator LM393), 12V PZ- (multi-tone high-gain buzzer), T1 transistor for driving PZ1, T2 transistor BC547 for driving 12V, relay (1C/O) for controlling a bulb (B1), and 10-kilo-ohm potentiometer VR1.
When the light drops on light dependent resistor (LDR1), its resistance extremely falls, which leads to activating an alarm to alert the user.The proposed system is appropriate for locking lockers, cash boxer, etc. This circuit is located in the locker or cash box in such a way that, when the robber opens it and uses a torch light to discover the valuables, light falls on light dependent resistor (LDR1), which performs as an electronic eye.
The signal o/p from the light dependent resistor (LDR1) is fed to IC2. The o/p from IC2 triggers the alarm when light falls on light dependent resistor during a robbery attempt.Similarly, bulb-B1 glows as a visual aware to prevent the burglary attempt.
If the reference voltage at pin-3 of IC2 is less than sensor voltage at pin -2 of IC2, o/p goes low routinely. This specifies that no light is dipping on the light dependent resistor. Low o/p of IC2 is fed to T1&T2. As a result, both are in cutoff state, so no flow of current through the beeper, keeping it in silent mode. Likewise, no flow of current in the relay, and so bulb B1 do not glow.
If the reference voltage at pin-3 of IC2 is superior than sensor voltage at pin-2 of IC2, o/p goes high automatically. This indicates that light is falling on LDR1. High o/p of IC2 is fed to T1 and T2. As a result, both transistors are in on (active) state. The flow of current through the buzzer & relay. The buzzer generates a loud alarm to alert you or people around you and, at the same time, bulb B1 glows as the circuit finishes through relay RL1’s contacts.
Operation of Electronic Eye Security System
- Initially, connect the circuit of the electronic eye security system as shown in the above circuit diagram on the bread board.
- Now connect the battery for the supply voltage of 9v.
- Place the LDR (Light Dependent Resistor) in the light.You can detect no sound is generated from the buzzer.
- Place the light dependent resistor in the dark, then the buzzer starts buzzing. Light emitting diode connected to the buzzer also starts flashing.
- As the light intensity dropping on the LDR growths sound generated by the buzzer increases.
Applications of Electronic Eye Security System
- This system can be used in door bell circuits.
- This can be used in a garage door opening and closing circuits.
- This system can be used in security applications.
Thus, this is all about electronic eye security system using photo-sensing (LM393). We hope that you have got a better understanding of this concept.Furthermore, any doubts regarding this concept or to implement any electrical and electronic projects, please give your valuable suggestions by commenting in the comment section below. Here is a question for you, What is the function of LM393?