Gas stove flame alarm circuit
Posted on Nov 10, 2015 10219
The circuit shown is the second natural gas (gas) stove flame alarm. After the gas stove ignited normal combustion, close the power switch S. Photoresistor RG due
to irradiation by light flame, its resistance is small, the transistor VT1 and VT2 conduction, the relay K pull its normally II1 contact K off, music Manifold IC does not sound. But once the gas stove flame, RG by light irradiation greatly reduced, the resistance increases, the Vri and VTZ off, the relay K to release, normally open contact K is closed, automatically turn on the power IC's source, lC work, the speaker BL Music issued warning to remind the main person close the gas valve. In addition to the circuit has been noted, a small relay selection JRX-13F, operating voltage of 12V. Transistor VT3 to 9014, available 3DG4M, instead of 3DG201,3DG401 or 3DG8A, B and so on. Adjustment potentiometer RP, can change the alarm sensitivity.