SIMPLE LPG/Butane/Propane GAS SENSOR CIRCUIT (TESTED OK)
If LPG used in kitchen is having leakage somewhere,how we come to know ? Since LPG is intentionally mixed with ethyl mercaptan for sensing gas leakage by its odor, we can suspect a leakage by its unpleasant smell. But while cooking dishes with variety of smell, recognizing the LPG smell may be little bit difficult .
Gas sensor circuits are very common nowadays but circuits having complications and confusions on sensor connections.. I have tried my best to introduce a very simple circuit, which is tested OK. Heart of this circuit is MQ 6 gas sensor, which is very sensitive for LPG ,iso butane & propane.
MQ 6 has an inbuilt heater where we have to supply 5V DC or AC for heating the coil. when coil is heat,Presence of LPG get sensed by the electrodes inside and the output goes high. This output is fed to the base of BC 548 and buzzer get ON . This is the basic theory of circuit.
Assemble this circuit and switch on the power.first we have to set the preset to hear the buzzer sound in the absence of LPG. then slowly rotate the preset PRECISELY to just eliminate the buzzer sound. Now light up a cigaratte lighter( cigarette lighter use butane) and blow off the flame with pressed condition.Bring the lighter (without flame) near the sensor. you can hear the buzzer beep loudly.Check with LPG also for fine tuning of preset .
if look at MQ 6 may lead you confusion because of its 6 pins .Actually 4 pin outs is sufficient for this ckt.
(ref picture.) leads A and A to be shorted . B and B to be shorted.H and H is the heater pins,where polarity is not an issue. AA and BB also can inter change. Only 4 pin outs to be used for the circuit.
given ckt is proved one(see video) and if you change the value of components or voltage or current, this circuit may not function.More over, MQ 6 sensor voltage should not exceed 5.1 voltage in any situation.
Where we can procure MQ 6 sensor? You can ask any electronic component dealer or you can get it by online shopping.( eg: www.electroncomponents.com)This costs around 150 - 175 Indian Rupees.
For the power supply of this ckt, I have used an
old mobile charger with 6V ,800mA as the power supply . When the LPG concentration in air is 200 to 10000 ppm(particle per million), sensor will detect and trigger the transistor .Preset adjustment is very important in this circuit. When gas is switch off,then also buzzer remains on for few seconds or may be 1- 2 minutes, Do not try to connect additional relay in this ckt because chance of spark between relay contact may leads to fire . In the video, buzzer hole is blocked because of its ear piercing sound irritation during my trials.sensor is kept around 30 cm away from burner and within 6-7 seconds buzzer statrts beeping.
Thanks & Regards
Vineesh Kodambattil
If LPG used in kitchen is having leakage somewhere,how we come to know ? Since LPG is intentionally mixed with ethyl mercaptan for sensing gas leakage by its odor, we can suspect a leakage by its unpleasant smell. But while cooking dishes with variety of smell, recognizing the LPG smell may be little bit difficult .
Gas sensor circuits are very common nowadays but circuits having complications and confusions on sensor connections.. I have tried my best to introduce a very simple circuit, which is tested OK. Heart of this circuit is MQ 6 gas sensor, which is very sensitive for LPG ,iso butane & propane.
Assemble this circuit and switch on the power.first we have to set the preset to hear the buzzer sound in the absence of LPG. then slowly rotate the preset PRECISELY to just eliminate the buzzer sound. Now light up a cigaratte lighter( cigarette lighter use butane) and blow off the flame with pressed condition.Bring the lighter (without flame) near the sensor. you can hear the buzzer beep loudly.Check with LPG also for fine tuning of preset .
if look at MQ 6 may lead you confusion because of its 6 pins .Actually 4 pin outs is sufficient for this ckt.
(ref picture.) leads A and A to be shorted . B and B to be shorted.H and H is the heater pins,where polarity is not an issue. AA and BB also can inter change. Only 4 pin outs to be used for the circuit.
given ckt is proved one(see video) and if you change the value of components or voltage or current, this circuit may not function.More over, MQ 6 sensor voltage should not exceed 5.1 voltage in any situation.
Where we can procure MQ 6 sensor? You can ask any electronic component dealer or you can get it by online shopping.( eg: www.electroncomponents.com)This costs around 150 - 175 Indian Rupees.
For the power supply of this ckt, I have used an
old mobile charger with 6V ,800mA as the power supply . When the LPG concentration in air is 200 to 10000 ppm(particle per million), sensor will detect and trigger the transistor .Preset adjustment is very important in this circuit. When gas is switch off,then also buzzer remains on for few seconds or may be 1- 2 minutes, Do not try to connect additional relay in this ckt because chance of spark between relay contact may leads to fire . In the video, buzzer hole is blocked because of its ear piercing sound irritation during my trials.sensor is kept around 30 cm away from burner and within 6-7 seconds buzzer statrts beeping.
Thanks & Regards
Vineesh Kodambattil
