Presented here is a 6v Laser security system that can be easily programmed for any password. This project powered using a mobile charger which gives 6 volts and 500 mA. It can also powered using battery ranging 6 volts. In this two 5v relays are used. There is a simple password setup using SPDT (single pole double throw) switch. Wiring the password setup needs some knowledge about SPDT switch.
6V laser security system circuit
Here I have wired in a such a way that the password is UP,DOWN,UP,DOWN. Here there are 16 possibilities. If you use centre positioned then there are 64 such possibilities. If the position of the switch is set correctly then the security can be disabled.
Firstly, setup the circuit leaving the LDR (light dependent resitor) out for the laser beam to be focused. power it up. Now the alam will be blown press the reset switch once. The alarm sound will be stopped. Once the beam of laser is crossed the alarm sound will start blowing and continuous until the push button (RESET) is pressed. You can use (circuit 2) in which the alarm is connected externally.
If you’re connecting external alarm don’t exceed current limit printed on relay.
• LDR (Light Dependent Resistor)
• 2 x 5 volt relays
• A momentary push button
• A buzzer (only for circuit no.1)
• 4 SPDT switch (you can use many switch to make you password complicated and unique)
• An old cell phone charger (But in working condition )
• 220 Ω resistor (220 ohms)
Feel interested? Check out other electronics projects.