Very Sensitive Fire Alarm Circuit Using Relay
by Utsource123 in Circuits > Sensors
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Very Sensitive Fire Alarm Circuit Using Relay
Hii friend,
Today I am going to make a circuit of Fire Alarm which is very sensitive.Today I will make this circuit using Relay and Transistor BC547.
Let's get started,
Components Required -
(1.) Photodiode x1
(2.) Buzzer x1
(3.) Relay - 6V x1
(4.) Transistor - BC547 x1
(5.) Battery clipper x2
(6.) Battery - 9V x2
Transistor - BC547
This is the pins of this transistor.
C - Collector,
B - Base and
E - Emmiter.
Connect Transistor to Relay
Firstly we have to connect transistor to the relay.
Solder Collector pin of transistor to coil-1 pin of the Relay as you can see in the picture.
Connect Photodiode
Next we have to connect Photodiode to the relay.
Solder Cathode leg of Photodiode to Coil-2 pin of Relay and
Anode leg of Photodiode to Base pin of the Relay as solder in the picture.
Connect Battery Clipper Wire
Next solder +ve wire of battery clipper to Coil-2 of Relay and
Solder -ve wire of battery clipper to emmiter pin of the transistor as you can see in the picture.
Next Connect Buzzer
Solder -ve pin of buzzer to common pin of the Relay.
Connect Second Battery Clipper
Now we have to connect second battery clipper wire to the circuit.
Solder +ve wire of battery clipper to +ve pin of buzzer and
solder -ve wire of battery clipper to NO (Normally Open) pin of the Relay as you can see in the picture.
Connect Batteries to Battery Clipper
How It Works
When fire will burn around this circuit with distance approx 5Cm then Buzzer will give sound automatically.
NOTE : We can also connect 3V LED to this circuit.Connect 3V LED with 220 ohm resistor in the parallel of Buzzer.
Thank you