2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 1/12

Q&AComments

LinksAdvertiseContactSubmitContest

RegisterLogin

µC »555AlarmsAudio

Basic

DIYHobby

LightsMeasurePower supply

RadioSolarTested

TheoryVarious »

Tools »

looking for something?

Search

Gas Leak Detector Circuit

Posted by P. Marian in 555, Alarms, ECE projects, Measure with 51 comments Tagged with: gas detectors•SEN-1327

34Like Share StumbleUpon Tweet 0 1

Enter the PCB design contest and win great prizes offered by FabStream.com

Here is a gas leak detector circuit that detects the leakage of LPG gas and alerts the user through audio-visual indications. The circuitoperates off a 9V PP3 battery. Zener diode ZD1 is used to convert 9V into 5V DC to drive the gas sensor module.

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 2/12

The gas leakage circuit uses the SEN-1327 gas sensor module from RhydoLABZ. Its output goes high when the gas level reaches orexceeds certain point. A preset in the module is used to set the threshold. Interfacing with the sensor module is done through a 4-pin SIPheader.

Pin details of the gas sensor module are shown in Fig. 2. An MQ-6 gas sensor is used in the gas sensor module. The sensor can also beused to detect combustible gases, especially methane.

Gas leak detector schematic

SEN1327 gas sensor pin details and picture

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 3/12

Whenever there is LPG concentration of 1000 ppm (parts per million) in the area, the OUT pin of the sensor module goes high. This

signal drives timer IC 555, which is wired as an astable multivibrator. The multivibrator basically works as a tone generator.

Output pin 3 of IC 555 is connected to LED1 and speaker-driver transistor SL100 through current-limiting resistors R5 and R4,

respectively. LED1 glows and the alarm sounds to alert the user of gas leakage. The pitch of the tone can be changed by varying preset

VR1. Use a suitable heat-sink for transistor SL100.

SEN-1327

34Like Share StumbleUpon Tweet 0 1

Find more projects

Search

Gas Detection Systemswww.acmeprod.com

Wired + wireless solutions for IAQ and

HVAC control in buildings.

Safety Equipment forGas

Combustible GasMonitor

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 4/12

SEN-1327 LPG

Gas Sensor

Module

Motion Detector

Alarm Circuit

Vibration

Sensor/Detector

Circuit

Fire Alarm Circuit

51 Responses to "Gas Leak Detector Circuit"

1. Jai Sudan says: on March 4, 2012 at 6:34 amreply

very nice project. Thanks for posting.

with regards,

Jai Sudan.

2. bhavin says: on March 20, 2012 at 8:27 pmreply

will i get this 4 – pin gas sensor in my local area??

or i should take it from net???

shruthi says: on June 20, 2012 at 11:57 amreply

Bhavin, you may get 4 pin assembled module from http://www.rhdolabs.com or have a look at the project list from

http://www.united77.com who have similar project based on LM324. I have bought one from United and is working fine.

sasi says: on July 19, 2012 at 7:17 pmreply

hai shuruthi how r u? where are you doing your degree.

i am sasi from ACTECH.

3. bijoy says: on March 23, 2012 at 6:15 pmreply

sir very important project,,,,,,,,thanks for shearing…………

vishnu says: on June 8, 2012 at 9:28 amreply

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 5/12

if you’ve this project report please please send me this because i’ve alredy done this project

kalpana says: on December 20, 2012 at 10:05 pmreply

please send me project report on Gas Leakage Detector

Amit says: on December 30, 2013 at 10:32 amreply

Hi,Any one can help me to get PCB design layout and what all material I need to do this project. this seems interesting projectand I want to do this for my project…. plz help me…

THANKS in advance

4. sonali says: on March 25, 2012 at 7:45 pmreply

sir please tell me out of the 6 pins of mq-6,which 4 do i need to use??

rehanul dhan says: on March 25, 2012 at 8:34 pm

reply

Mq-6 is the material name of this sensor.mq-6 material is semicircle shaped material..you need SEN1437 to use the gasleakage circuit…SEN1437 has four pin component.first pin is OUTPUT,second pin is ANG,third pin is VCC,last one is GND…

rehanul dhan says: on March 25, 2012 at 8:41 pmreply

Sorry,i mistake on this post..sensor is SEN1327..

5. rehanul dhan says: on March 25, 2012 at 8:16 pm

reply

Its very important project.,very nice…

I have prepared this detector…its most useful in home..

6. chandra.d says: on March 26, 2012 at 3:52 pmreply

sir,could this gas leakage detector detect the type of gas N.G.V ? , FOR CAR USES.

7. vishnu says: on March 28, 2012 at 11:23 amreply

sir i’ve used MQ-6 gas sensor.but no 4 pin sip header.so i soldered the sensor & take the pins.as soon as switch is closed alarmsounds.whats the problem? kindly reply me.

8. sonali says: on March 29, 2012 at 3:25 pmreply

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 6/12

but sir this sen-1327 is not available in market….only 6 pin sensor is available..so what do i do??

9. praneeth says: on April 18, 2012 at 1:13 pm

reply

Where can I found SEN-1327? Pls reply..

10. shiva says: on April 22, 2012 at 12:28 pmreply

if gas leaks and when the ckt gets triggered,there is possibility of spark.!!

11. Ur's Mani says: on April 29, 2012 at 2:59 pmreply

nice and useful project & i want many project…….

12. VIRA says: on May 16, 2012 at 9:48 pm

reply

HOW MUCH IT(SEN1327) COSTS???

13. amos says: on May 18, 2012 at 12:33 pmreply

can i use this circuit with gsm sms sending circuit

14. morteza says: on June 6, 2012 at 4:04 pmreply

this project is very good.

a have an answer.dose this circut detect a cng gas????(cng=home usable gas)

15. telmon says: on June 8, 2012 at 12:45 am

reply

hi pls i bought an mq-2 gas sensor could you pls email me how to connect it with this circuit

16. RK Murthy Challa says: on June 8, 2012 at 7:20 pmreply

It is an excellent project in view of security. Please let know shall I get the Sensor MQ-6 freely or let me inform where can I

purchase.

Than Q

17. sudheer says: on June 8, 2012 at 7:54 pm

reply

i didn’nt get sen 1327 gas sensor in warangal(A.P).from wer i can get it?

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 7/12

18. kavi says: on June 9, 2012 at 7:59 pmreply

where i can get mq-6 & 1327 sensor.. how much is the cost of entire circuit… pls pls pls reply…

19. Naveed Shahzad says: on June 10, 2012 at 10:14 am

reply

very nice project thanks for posting

20. mukesh kumar says: on June 14, 2012 at 9:04 pm

reply

can u plz tell the approx price of SEN1327

21. veni says: on August 3, 2012 at 3:13 amreply

i already have this gas sensor how to connect this circuit is it need gas cylinder to get the output of this ckt

Jim Keith says: on August 3, 2012 at 4:55 am

reply

Test with unlit propane torch or gas stove burner.

22. priya says: on August 9, 2012 at 9:32 pmreply

sir ,Gas leakage alarm praticaly implement which type problem faced,plz gives the solution.thanks

23. a.loganathan says: on August 16, 2012 at 9:30 am

reply

nice projecttttttttt…….

24. jhewill says: on August 23, 2012 at 9:44 am

reply

hellow!! can i replace mq 6 to mq 7???is that okay?

25. xie xie says: on September 1, 2012 at 1:23 pmreply

sir is this a multi gas detector,. ist can detect methane, carbon dioxide, and nitrogen???

26. akash says: on September 23, 2012 at 3:01 pm

reply

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 8/12

gas sensor has 6 terminal so tell me how can i connect this in circuit ? becoz in circuit their is only give 4 terminal

27. shubhankar says: on September 24, 2012 at 11:29 am

reply

sir i want to get the circuit diagram with proper specification of lpg sen-1327 or mq-6 gas sensor.please help me;;;

28. Priyadarsan says: on October 2, 2012 at 8:22 am

reply

Does anyone know how the values of the resistors and capacitors were designed? Can you post the calculation please.

29. prasanta nayak says: on October 14, 2012 at 9:53 am

reply

sir plz send kv(low ampere) voltage tripler ckt diagrma

30. yogitha says: on October 16, 2012 at 7:16 am

reply

nice project

31. prashant manakar says: on October 22, 2012 at 10:12 amreply

whats price for this leak detector

32. nandhini says: on December 21, 2012 at 5:51 pm

reply

may i know what is the use of zener diode in this circuit?

33. nandhini says: on December 21, 2012 at 5:53 pm

reply

may i know how the transistor is used in this circuit?

34. Jim Keith says: on December 21, 2012 at 6:23 pm

reply

The transistor is simply an amplifier that drives the loudspeaker.

35. fou says: on May 21, 2013 at 5:47 pm

reply

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 9/12

hi sir,its the best project and i am using the same project now for my graduation project.. our teacher told us to add a display unit to

see at which range the sensor will detect and gives alarm.. i have used MQ-6 instead of SEN1327 and its working very good..

but i have some difficulty in making the project report and getting out the spicifications of this circuit.. so please can you help mewith that i have only 2 more weeks to submit my project and without these things i will fail

36. Rajesh pandey says: on July 19, 2013 at 10:17 am

reply

sir please tell me the pin no.2 i.e. analog pin where it is connect

37. pedram says: on July 23, 2013 at 11:05 pm

reply

Do any one know can I use mq9 instead of mq6?

38. pedram says: on July 23, 2013 at 11:07 pmreply

I want detect co, I found that mq9 is better than the other mq family do anyone help me?

39. sai giridhar says: on August 23, 2013 at 2:38 pm

reply

Hello sir. I’m doing a mini project on this. Rather than using mq6 sen1327 ,can i use MQ5 sen-2060 ? will it work?why sl100 transistor is used ? is thr any specific purpose or any random transistor amplifier can be used?

Jim Keith says: on August 23, 2013 at 3:46 pm

reply

There are a number of issues with this circuit–while it may work OK as shown, the power consumption is far too high

(>1W) for battery operation. My suggestion is to power it via a regulated 5V from a wall wart and eliminate the 5V zenerand R1. Or use an unregulated wall wart with a properly heat-sinked LM7805 voltage regulator.

Also, pin 4 of the 555 makes a poor threshold detector –the TLC555 is better–see my post on the 555:

http://www.electroschematics.com/7195/quirky-555-timer-reset-function/

To make the MQ5 sen-2060 work, R3 must be a pot wired as a variable resistor–I suggest 100K because it does notseem to specify the internal resistance range in the spec sheet.

http://www.parallax.com/Portals/0/Downloads/docs/prod/sens/MQ-5.pdf

On the SL100 transistor, I would use any NPN transistor–if it runs too hot, go with a TO-220 power transistor. Run the

speaker directly off the unregulated supply for more audionvolume.

40. sabahath nabeela says: on September 15, 2013 at 3:41 pmreply

sir,plz tell me where to connect analog pin(pin-2)of the sensor.explain working of the circuit

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 10/12

41. Amit says: on December 30, 2013 at 10:34 am

reply

Hello ALL,Any one can help me to get PCB design layout and what all material I need to do this project. this seems interesting project and I

want to do this for my project…. plz help me…

THANKS in advance

42. Afzal says: on January 30, 2014 at 3:23 pmreply

sir , i selected this as my mini project.

so pls give me a complete working this circuit describing each and every component

What do you think about this article? Leave a comment!

Name (required)

Mail (will not be published) (required)

Website

Check this box to get notifications via e-mail on new comments.

Submit Comment

6552 subscribers Online visitors

ElectroSchematics Partners

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 11/12

socialize with us

Login

Username

Password

Remember Me

Log In

RegisterLost Password

Recent Questions

how to make a long range fm receiver?

Can anybody suggest me ADCs and DACs type and applications in the real time.I am looking to design a solar 6v lead acid battery charger which will power an Arduino and servo motor.

recently added electronic circuits

Basic Bitwise Operators + (Part 2) – Tutorial #9

High Power LED Dimmer Circuit

DIY Solar Boost Converter with MPPT Charge Controller

Become our friend on Facebook!

2/10/2014 Gas Leak Detector Circuit

http://www.electroschematics.com/6665/gas-leak-detector-circuit/ 12/12

Electro Schematics

25,205 people like Electro Schematics.

Facebook social plugin

Like

Policy - Disclaimer - © Copyright 2008 - 2014