Emergency Buzzer alarm!

Emergency Buzzer alarm!

Hello, Everyone today in this article I want to discuss simple emergency Buzzer alarm Circuit. The circuit consists of some basic components like resistors,  Transistors, Buzzer alarm, and a LED. You can run the circuit between 9v to 12v of voltage. If you cut the loop wire then the buzzer and the LED will be On condition.

Needed components:

1. Red LED
2. Buzzer 5v
3. 680 Ohm resistor
4. 2.2k Ohm resistor
5. BC548B NPN Transistor
6. 9v Battery
7. 9V Battery Clip

Indian link for Buying:

Amazon.in: 


LED: https://amzn.to/2SdNcdt

Buzzer: https://amzn.to/2S97954

Different values of resistor: https://amzn.to/2t7FxOF

9v Battery: https://amzn.to/2GcseVX

9v Battery Clip: https://amzn.to/2TwOvkj

BC548B NPN Transistor: https://amzn.to/2SaC15i

International links for Buying:

Bangood.com:


 LED: https://www.banggood.in/custlink/3mDvySETET

Buzzer: https://www.banggood.in/custlink/Gv3GRIhuJr

Different values of resistor: https://www.banggood.in/custlink/KDvGYIdTJt

9v Battery: https://www.banggood.in/custlink/DKDvyZh1FJ

9v Battery Clip: https://www.banggood.in/custlink/Km33E8h7JI

BC548B NPN Transistor: https://www.banggood.in/custlink/mKmvh8ywVK



Amazon.com:

 LED: https://amzn.to/2MTAwSR

Buzzer: https://amzn.to/2t9SszE

Different values of resistor: https://amzn.to/2t9CO7w

9v Battery: https://amzn.to/2TvDCip

9v Battery Clip: https://amzn.to/2t7OV4Q

BC548B n-p-n Transistor: https://amzn.to/2GrRkza

YouTube Video:

Watch the YouTube video from Creative Creator for more information about Emergency Buzzer alarm.

Circuit Schematics:

How the circuit works?

This is a basic NPN Transistor Circuit which is used in the circuit.  The basic principles NPN  transistor is that if you give voltage into the transistor's base then the transistor became conductive and current flows from transistor's collector to Emitter. If you connect any series load then the circuit will run the load.

1. At first, the loop wire is connected. so it means that the Base and the Emitter point is short-circuited. So, for this reason, the current goes to the shortest path as possible. So current will flow from Vcc to GND through 2.2k Resistor. So, no current will flow into the transistor's base and for this reason, the transistor will not be conductive. As a result, the current will flow from collector to Emitter. And for this, the LED and the Buzzer will not work.
2. Now let's say I have cut the wire which is short-circuited before. (I mean  Base and Emitter Connected wire). Now if we turn on the power supply then the current flows from Vcc to transistor's Base through 2.2k Resistor. For this reason, the transistor became conductive and the current flows from the Transistor's collector to Emitter and the load which is connected in series will be on for this reason. (Here the load is parallelly connected RED LED and the Buzzer).  For this reason, the buzzer gives beep sound. And the circuit will work. 

Note: 

Always check the Transistor number before using it. Otherwise, it may be a PNP transistor.
Check out all the data sheet and pinouts. A different transistor has different pin numbering.





        That is all about his topic hope you guys enjoy. You can also read our previous topic of the video: http://bit.ly/2WdEjPs