Feature:When alcohol vapor exists in the environment where the sensor MQ-3 is located, the conductivity of the sensor will increase as the alcohol vapor concentration increases. By measuring the series partial pressure between the sensor and the fixed resistor, the alcohol content in the environment can be determined.Working voltage: 5-7.5V DCPCB size: 6.2*3.6cmCircuit description:This circuit can be powered by a 5-7.5 volt DC power supply. The switch S1 is a power switch. The resistor R1 and the light-emitting diode D1 are used for power indication. The sensor MQ-3 needs to be heated to a certain temperature during operation, so there is a section of electric heating installed inside it The wire and resistor R4 are the current-limiting resistance of the heating wire. It is normal for the MQ-3 to generate heat after being energized. When MQ-3 does not detect alcohol vapor, its internal resistance is very large, the voltage drop of R3 and RW is very low, the voltage of pin 2 of NE555 is lower than the trigger voltage (VCC/3), its pin 3 outputs high level, D2 goes out , The buzzer does not sound, and the relay does not operate. When MQ-3 detects alcohol vapor, the internal resistance drops, the voltage of R3 and RW rises, the voltage of pin 2 of NE555 is higher than the trigger voltage, pin 3 becomes low level, D2 turns on and emits light, and the buzzer flows The current starts to sound, and the electromagnetic coil in the relay is energized to attract the switching action. In
This Discount Coupon Offer will end today. Click the View Coupon link button now to see the Full Product Details, Product Specifications and Current Discount Offer Price from the Vendor or Merchant Website. Coupon Code will be automatically applied to your shopping cart during checkout from offer website if you decide to buy this discount offer today.
Buy High Quality and Cheap Alcohol Tester Kit MQ-3 Detection Sensor Module Welding Training DIY parts and get it delivered to Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming.
Disclosure: This post may contain affiliate links, which means that we may receive a small commission if you click the link and purchase something that we recommended to you. Read more about Affiliate disclosure on our Terms and Conditions Page.