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Fire Detection Alarm System DIY Experiments Science STEM KIT (Assembled), 100% Tested

(12 customer reviews)

327.18 + GST

1.Fire detection Alarm System assembled Kits 100% Tested .
2. Full documentation, includes Circuit diagrams, PCB Layout, Testing document, etc.
3. Videos are available on YouTube for easy understanding
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68 in stock

This item: Fire Detection Alarm System DIY Experiments Science STEM KIT (Assembled), 100% Tested

68 in stock

327.18 + GST
327.18 + GST
409.18 + GST
1,248.26 + GST
236.98 + GST
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Fire Detection Alarm System circuit is presented here is based on the readily available Flame Sensor, comparator IC LM393 and relay. The Flame sensor is used as the fire intensity detector while IC LM393 used as comparator. In the absence of fire, no fire on the flame sensor. As a result flame sensor stop conducting and buzzer stays off. However, when there is fire on the flame sensor, flame sensor starts conducting and buzzer sound.

Application of the circuit:

Most of the flame sensor based circuits available in market use one or another kind of flame sensor which increases the cost and also require complicated circuitry around it. But this flame sensor based circuit uses readily available flame sensor as fire detector. The functioning of this Fire Detection Alarm System circuit is to detect fire and automatically activate the buzzer in presence of fire. Buzzer sound continuously indicating the presence of fire till there is fire.

Why this particular circuit:

Flame sensor used here as a fire detector. The circuit operates normally over a DC voltage of 5V which can be obtained by DC supply cable.

Explained working of circuit:

The basic idea behind the circuit operation is to turn ON buzzer in presence of fire. The flame sensor is needed for this purpose. Flame sensor is device that converts heat to electric energy. Here, Fire Detection Alarm System circuit works as fire detector while flame sensor turns on the buzzer. IC LM393 is used as comparator. Flame sensor output is connected as input to comparator.? Pin no. 4 of LM393 is pulled towards ground. Relay is used as a switch. When relay is activated, normally closed contact becomes open and normally open contact becomes closed. In normal condition, when there is no fire and buzzer stays off. Now consider second scenario when there is fire, the buzzer sound in the presence of fire.

How to build:

First of all read the given manual thoroughly and study the circuit given in the figure. Also have look at PCB and components supplied along with the kit. Each component has to be soldered in its position on PCB.

Identification of resistors is done by color coding. The color band on each resistor corresponds to its exact value.

There are different methods in which values are defined on capacitors. But usually values are specified numerically on them.

Can you make out the whole working of circuit and are you able to identify each component separately as to where each of them has to be placed?

If yes only then proceed further to actually mounting and soldering the parts.

Not ICs but their sockets are to be soldered on PCB. This is to make mounting and dismounting of ICs easy while troubleshooting.

Start from left most corner of PCB and solder the components one by one on their correct position on PCB.

Before soldering any component see that you have placed it at its right position and with correct polarity. Give due attention to diodes and electrolytic capacitors as they are polarity dependent.

Do the soldering of other components in the same way while keeping in mind that components with long and sensitive leads like capacitors and transistors are soldered last.

Testing the kit:

After assembling and soldering of components on PCB, connect external DC power source of 5V.

For testing purpose manually hold fire over flame sensor. Buzzer sound in this case.

Now set the desired intensity at which you want detection of fire. This can be done by changing the resistive value of R2 variable resistor.

Install the unit at ceiling of room.

ICs used here:

The only IC used here is LM393

It is dual differential comparator IC.

This 8 pin IC is popular and commonly used IC

Part List:


U1 ? ? ? ? ? ? ? ??? – LM393

Base? ? ? ? ? ? ??? – 8 pin

Resistors(all ? watt +/-5% carbon unless stated otherwise)

R2 ? ? ? ? ? ? ? ??? – 10k Ohm(variable)

R3 ? ? ? ? ? ? ? ??? – 1k Ohm

R4 ? ? ? ? ? ? ? ??? – 1k Ohm

R5 ? ? ? ? ? ? ? ??? – 10k Ohm

R6 ? ? ? ? ? ? ? ??? – 10k Ohm


C1 ? ? ? ? ? ? ? ??? – 1uF


D4:? ? ? ? ? ? ? ??? – Flame Sensor

D1:? ? ? ? ? ? ? ??? – Red LED

D2:? ? ? ? ? ? ? ??? – Green LED

5 V USB Cable






12 reviews for Fire Detection Alarm System DIY Experiments Science STEM KIT (Assembled), 100% Tested

  1. Lokesh (verified owner)

    Drone parts i ordered and found ok

  2. Rahul (verified owner)

    Drone parts i ordered and found ok

  3. Paaji (verified owner)

    Online best cost electronic components

  4. Devendra (verified owner)

    Less cost than other websites

  5. Rahul (verified owner)

    Online best cost electronic components

  6. Vivek (verified owner)

    Very well worth the money.

  7. Vivek (verified owner)

    Good support and recommended

  8. Ketan (verified owner)

    Online best cost electronic components

  9. Priya (verified owner)

    Drone parts i ordered and found ok

  10. Rahul (verified owner)

    Very fast delivery.

  11. Harsh (verified owner)

    I got my project done with these components Great Support

  12. Rahul (verified owner)

    Good service.

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