Posted by Circuits Arena on Saturday, 17 January 2015
Alcohol Tester Circuit Diagram is the artlcle explaining Alcohol Tester : A lot of accidents happen daily attributable to drunk driving. this can be a awfully helpful circuit for testing wheth...
Alcohol Tester:
A lot of accidents happen daily attributable to drunk driving. this can be a awfully helpful circuit for testing whether or not a driver is drunk or not. Alcohol Tester circuit is straightforward to use, cheap and indicates numerous levels of alcohol consumption through LEDs.
Circuit and dealing
Fig. one shows circuit of the alcohol level tester. Alcohol detector MQ3 is employed here to notice the alcohol fumes’ concentration.
Pins a pair of and five of MQ3 square measure connected to 5V power offer and also the ground, severally, as shown within the circuit. These pins are literally the heating-coil pins of the detector. The input pins one and three of the detector are connected to 5V. Pins four and half dozen square measure connected to input pin five of LM3914 (IC1).
The number of glowing LEDs indicates the concentration level of alcohol detected by the detector. resistance R1 and predetermined VR1 square measure accustomed calibrate the output voltage from the detector.
When a drunk breathes out close to sensor1, the
alcohol vapours are available contact with MQ3 detector and its resistance changes. This raises amplitude at pin five of IC1 a bigger range of LEDs begin glowing than the 2 that were glowing before.
Fig.The alcohol tester’s circuit diagram.
Construction and testing:
An actual-size, single-side PCB for the alcohol level tester is shown in Fig. a pair of and its part layout in Fig. 3. once collecting the circuit on PCB, enclose it during a appropriate case.
Switch on the circuit and verify the take a look at points mentioned within the table. Before mistreatment the circuit, vary VR1 till LED1 and LED2 glow once the detector is in traditional atmosphere. currently open the cork of associate alcohol bottle and convey it close to sensor1. you may notice that LED3, LED4 and LED5 conjointly begin glowing. As you bring the alcohol bottle’s open mouth terribly near sensor1, all the LEDs (LED1 through LED10) can begin glowing.
We don't advocate that you simply truly consume some alcohol to check the circuit. The on top of take a look at with a bottle of alcohol, or its sample during a little glass, ought to serve for many functions. till you discover a drunk, of course
