{"title":"Gas \u0026 Air Quality Sensors","description":"\u003cp\u003eGas and air-quality sensors detect smoke, LPG, alcohol, CO2, VOCs and dust for leak alarms, room monitors and air-quality stations.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMQ sensors\u003c\/strong\u003e (MQ-2, MQ-135 and others) use a heated element whose resistance changes with the gas around it. Most modules give an analog output for the level and a digital output that switches at a threshold set by a potentiometer.\u003c\/li\u003e\n\u003cli\u003eFor real CO2, the \u003cstrong\u003eMH-Z19B and MH-Z19E\u003c\/strong\u003e are NDIR sensors that measure carbon dioxide directly; the MH-Z19B reports it over UART.\u003c\/li\u003e\n\u003cli\u003eThe \u003cstrong\u003ePMS5003\u003c\/strong\u003e counts PM2.5 particles for dust and smoke monitoring.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eHow to choose:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eStart from the gas you care about. Each MQ number targets different gases.\u003c\/li\u003e\n\u003cli\u003eDecide whether you need a trend, which any of these give, or a calibrated number, which needs more care.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eHeated sensors need a warm-up before readings settle, and most need calibrating in clean air. They work with Arduino and ESP32. Treat a DIY gas alarm as an early warning, not a certified safety device.\u003c\/p\u003e\n\u003ch2\u003eFrequently asked questions\u003c\/h2\u003e\n\u003ch3\u003eWhich MQ sensor should I buy?\u003c\/h3\u003e\n\u003cp\u003eIt depends on the gas. Each MQ number targets different gases, such as smoke and LPG, or air quality.\u003c\/p\u003e\n\u003ch3\u003eCan an MQ sensor measure CO2?\u003c\/h3\u003e\n\u003cp\u003eNot reliably. For carbon dioxide use an NDIR sensor such as the MH-Z19B, which measures CO2 directly.\u003c\/p\u003e\n\u003ch3\u003eWhy do readings drift at first?\u003c\/h3\u003e\n\u003cp\u003eHeated sensors need a warm-up period, and calibration in clean air, before readings settle.\u003c\/p\u003e\n\u003ch3\u003eCan a DIY gas sensor replace a certified alarm?\u003c\/h3\u003e\n\u003cp\u003eNo. Use it as an early-warning project, not a safety device.\u003c\/p\u003e\n\u003ch2\u003eGuides\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/guides\/how-does-an-mq-gas-sensor-work\"\u003eHow Does an MQ Gas Sensor Work?\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/guides\/bme680-explained-how-it-measures-air-quality-and-how-to-wire-it-to-an-arduino-uno\"\u003eBME680 Explained: How It Measures Air Quality, and How to Wire It to an Arduino Uno\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"Which MQ sensor should I buy?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"It depends on the gas. Each MQ number targets different gases, such as smoke and LPG, or air quality.\"}}, {\"@type\": \"Question\", \"name\": \"Can an MQ sensor measure CO2?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Not reliably. For carbon dioxide use an NDIR sensor such as the MH-Z19B, which measures CO2 directly.\"}}, {\"@type\": \"Question\", \"name\": \"Why do readings drift at first?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Heated sensors need a warm-up period, and calibration in clean air, before readings settle.\"}}, {\"@type\": \"Question\", \"name\": \"Can a DIY gas sensor replace a certified alarm?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"No. Use it as an early-warning project, not a safety device.\"}}]}\u003c\/script\u003e","products":[{"product_id":"gp2y1010au0f-pm25-dust-sensor-sharp-optical-smoke-detector-compoden","title":"Sharp GP2Y1010AU0F Optical Dust Sensor (PM2.5) | Compoden","description":"\u003ch1\u003eSharp GP2Y1010AU0F Optical Dust Sensor – PM2.5 Particle Sensor\u003c\/h1\u003e\n\n\u003cp\u003eSharp GP2Y1010AU0F is an optical dust sensor that detects fine particles such as smoke, pollen, and dust in the air. It emits an infrared beam and measures the reflected light, outputting an analog voltage proportional to particle concentration. This compact module integrates easily with microcontrollers, making it ideal for air quality monitoring, HVAC systems, and DIY pollution trackers.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5 V DC (VCC), 5 V (V-LED)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCurrent Consumption\u003c\/td\u003e\n\u003ctd\u003e20 mA max (VCC), 10 mA (ILED)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e0 – 0.5 mg\/m³ (typical)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Voltage\u003c\/td\u003e\n\u003ctd\u003e0.5 – 2.5 V (cleaned air – high dust)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd\u003e-10 °C to +65 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e46 × 30 × 17.6 mm (W×D×H)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003eIndoor air quality monitor with real‑time PM2.5 display\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-forest-fire-early-warning-kit-with-arduino-uno-plus-sensor\"\u003eSmoke-particle sensing demo for a fire-warning learning project\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eAutomated ventilation control based on dust levels\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/arduino-nano-33-iot-data-logging-project-kit\"\u003eData‑logging pollution tracker with IoT dashboard\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThis sensor outputs an analog signal in the 0–5 V range, so it works with any microcontroller that has an ADC accepting 5 V. Popular choices: Arduino Uno, Mega, Nano (5 V boards) directly; ESP32\/ESP8266 (3.3 V logic) require level shifting on analog input, or use a voltage divider. Raspberry Pi needs an external ADC (e.g., MCP3008). The sensor’s V‑LED pin should be driven intermittently to prolong IR LED life, but can be tied to VCC for continuous operation.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eTypical wiring: pin 1 (V-LED) to 5V through 150 Ω with 220 µF to GND, pin 2 (LED-GND) to GND, pin 3 (LED) to a digital pin that pulses the LED, pin 4 (S-GND) to GND, pin 5 (Vo) to A0, pin 6 (Vcc) to 5V. For best accuracy, read Vo during the LED‑ON pulse (pulsed from the digital pin on pin 3, LED).\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, the GP2Y1010AU0F works directly with 5 V Arduino boards. Connect Vo to any analog pin and read the voltage. Many Arduino libraries are available for straightforward integration.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I calibrate the sensor for accurate PM2.5 readings?\u003c\/summary\u003e\u003cp\u003eThe sensor outputs a voltage linearly related to dust density. Zero‑dust voltage is typically around 0.5 V. Use a reference instrument or clean environment to establish calibration points, then map the output to µg\/m³.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I run the LED continuously?\u003c\/summary\u003e\u003cp\u003eContinuous 5 V on V‑LED will work but shortens the IR LED lifespan. The datasheet recommends a 10 ms pulse \/ 10 ms off cycle for long‑term use. Most libraries implement pulsing by connecting the LED pin (pin 3) to a digital pin.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53444956651885,"sku":"CDN-0271","price":370.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/gp2y1010au0f-pm25-dust-sensor-sharp-optical-smoke-detector-compoden-4212554.jpg?v=1790780167"},{"product_id":"mq6-lpg-gas-sensor-module-compoden","title":"MQ6 LPG Gas Sensor Module - Compoden","description":"\u003ch1\u003eMQ6 Gas Sensor Module — LPG, Butane, Propane Detection\u003c\/h1\u003e\n\n\u003cp\u003eThe MQ6 gas sensor module is designed to detect combustible gases such as LPG, iso-butane, and propane. It provides an analog output that rises with gas concentration, for learning projects and data logging. It is not a certified gas detector. Its high sensitivity and fast response time ensure reliable performance in both hobbyist and industrial applications.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetectable Gases\u003c\/td\u003e\n\u003ctd\u003eLPG, iso-butane, propane\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog (0–5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e200–10,000 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePreheat Time\u003c\/td\u003e\n\u003ctd\u003e~20 seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e32mm x 22mm x 27mm\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-lpg-gas-leak-alarm\"\u003eLPG reading display with an LED threshold indicator\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eSmart kitchen safety device with IoT alerts using ESP8266\u003c\/li\u003e\n  \u003cli\u003e\n  \u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/esp8266-d1-mini-data-logging-project-kit\"\u003eIndustrial gas monitoring node with data logging to SD card\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eWorks with 5V microcontrollers such as Arduino Uno, Mega, Nano. Also compatible with ESP8266 and ESP32 when using the analog input pin. The module outputs 0–5V analog signal, so an ADC is required. Pair with a relay module for automated gas shut-off systems.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, and AO to an analog input (e.g., A0 on Arduino). Allow 20–30 seconds for preheating. Ensure sensor is placed in a well-ventilated area to prevent false triggers. Pull-up resistors are not needed as the module includes built-in conditioning circuitry.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino Uno?\u003c\/summary\u003e\u003cp\u003eYes, the MQ6 module works with Arduino Uno. Connect AO to analog pin A0, and read the voltage to determine gas concentration.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes it detect natural gas (methane)?\u003c\/summary\u003e\u003cp\u003eThe MQ6 is optimized for LPG and propane. For methane, consider the MQ4 sensor. The MQ6 may show some response to methane but not as accurate.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I calibrate the sensor?\u003c\/summary\u003e\u003cp\u003eCalibration involves exposing the sensor to a known gas concentration and adjusting the load resistor. For basic applications, the pre-calibrated module provides sufficient sensitivity.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53444959437165,"sku":"CDN-0344","price":95.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq6-lpg-gas-sensor-module-compoden-3482983.jpg?v=1790780107"},{"product_id":"mq2-gas-sensor-module-for-smoke-lpg-alcohol-detection","title":"MQ-2 Gas Sensor Module (Smoke, LPG, Alcohol) for Arduino","description":"\u003ch1\u003eMQ2 Gas Sensor Module – Smoke, LPG, and Alcohol Sensing\u003c\/h1\u003e\u003cp\u003eThe MQ2 gas sensor module is a versatile sensor for detecting combustible gases such as LPG, smoke, alcohol, propane, hydrogen, and methane. It provides an analog voltage output that varies with gas concentration, making it ideal for DIY air quality monitors and gas-sensing learning projects. With high sensitivity and fast response, it is a reliable choice for both hobbyist and educational projects.\u003c\/p\u003e\u003cp\u003eA sensor for learning projects; not a certified gas or smoke detector.\u003c\/p\u003e\u003ch2\u003eKey Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDetecting Concentration\u003c\/td\u003e\n\u003ctd\u003e200-10000ppm (combustible gas)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAnalog Output\u003c\/td\u003e\n\u003ctd\u003e0-5V, proportional to gas concentration\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePreheat Duration\u003c\/td\u003e\n\u003ctd\u003eOver 20 seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInterface\u003c\/td\u003e\n\u003ctd\u003eAnalog pin + digital threshold (comparator)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e32mm x 22mm x 27mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/kit-industrial-gas-leak-detector-kit\"\u003eSmoke sensor relay trigger project\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/kit-smoke-and-fire-safety-system\"\u003eSmoke sensing demo for learning how gas sensors respond\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003ePortable breathalyzer for alcohol detection\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/esp32-air-quality-monitoring-cube-kit-50mm-cube-with-oled-aqi-display\"\u003eAir quality monitoring station with data logging\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility\u003c\/h2\u003e\u003cp\u003eThis module operates at 5V and works seamlessly with Arduino boards (Uno, Nano, Mega) and Raspberry Pi (with an ADC if needed, as Pi lacks analog inputs). It outputs an analog signal (0-5V) that can be read by any analog input pin. For 3.3V systems, a level shifter is recommended to avoid damage.\u003c\/p\u003e\u003ch2\u003eWiring Notes\u003c\/h2\u003e\u003cp\u003eConnect VCC to 5V, GND to ground, and the analog output (A0) to an analog input pin on your microcontroller. Let the sensor preheat for 20-30 seconds before taking readings. Avoid operating in high-humidity or dusty environments for accurate measurements.\u003c\/p\u003e\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino Uno?\u003c\/summary\u003e\u003cp\u003eYes, the MQ2 sensor module works directly with Arduino Uno. Connect the analog output to any analog pin and use a simple sketch to read gas concentration levels.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eHow do I calibrate the MQ2 sensor?\u003c\/summary\u003e\u003cp\u003eCalibration involves exposing the sensor to a known gas concentration and adjusting the threshold in your code. For general use, you can use pre-calibrated values from the datasheet and fine-tune based on ambient air readings.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eCan it detect carbon monoxide?\u003c\/summary\u003e\u003cp\u003eThe MQ2 is sensitive to many combustible gases, including carbon monoxide (CO), but it is not specific to CO. For dedicated CO detection, consider the MQ7 sensor.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53444960354669,"sku":"CDN-0374","price":95.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq2-gas-sensor-module-for-smoke-lpg-alcohol-detection-5934700.jpg?v=1790780106"},{"product_id":"mq-8-hydrogen-gas-sensor-module-for-h2-detection-compoden","title":"MQ-8 Hydrogen Gas Sensor Module for Arduino","description":"\u003ch1\u003eMQ-8 Hydrogen Gas Sensor Module — Senses H2, LPG, Alcohol\u003c\/h1\u003e\u003cp\u003eThe MQ-8 is a semiconductor gas sensor module designed to detect hydrogen (H2) concentrations. It is also sensitive to LPG and alcohol vapours. Ideal for DIY hydrogen-sensing projects and experiments.\u003c\/p\u003e\u003ch2\u003eKey Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeater Consumption\u003c\/td\u003e\n\u003ctd\u003e~150mA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e100~10000ppm H2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput\u003c\/td\u003e\n\u003ctd\u003eAnalog voltage (0-5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarm-up Time\u003c\/td\u003e\n\u003ctd\u003e20 seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSensitivity\u003c\/td\u003e\n\u003ctd\u003eAdjustable via potentiometer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eHydrogen level sensing demo for a battery bench\u003c\/li\u003e\n\u003cli\u003eDIY breathalyzer (alcohol tester)\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/kit-industrial-gas-leak-detector-kit\"\u003eGas sensor relay trigger project\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003ePortable air quality monitor\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility\u003c\/h2\u003e\u003cp\u003eWorks with 5V microcontrollers like Arduino Uno, Mega, NodeMCU. Raspberry Pi requires an external ADC. Common pairings include Arduino for analog reading.\u003c\/p\u003e\u003ch2\u003eWiring Notes\u003c\/h2\u003e\u003cp\u003eConnect VCC to 5V, GND to ground, and AOUT to an analog input pin. The sensor draws ~150mA; ensure adequate power. Allow 20-second preheat for stable readings.\u003c\/p\u003e\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, it outputs an analog signal readable by any Arduino analog input pin. Works directly with 5V microcontrollers.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eCan it detect other gases?\u003c\/summary\u003e\u003cp\u003eIt is primarily for hydrogen but cross-sensitive to LPG and alcohol; not suitable for precise multi-gas measurements.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eHow long does it last?\u003c\/summary\u003e\u003cp\u003eTypical lifetime is about 5 years in clean air, longer if rarely exposed to high gas concentrations.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53444960977261,"sku":"CDN-0392","price":110.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-8-hydrogen-gas-sensor-module-for-h2-detection-compoden-1907032.jpg?v=1790780106"},{"product_id":"winsen-mh-z19e-ndir-co2-sensor-air-quality-monitor","title":"Winsen MH-Z19E NDIR CO2 Sensor Air Quality Monitor","description":"\u003ch1\u003eWinsen MH-Z19E NDIR CO2 Sensor for Air Quality Monitoring\u003c\/h1\u003e\n\n\u003cp\u003eThe Winsen MH-Z19E is a non-dispersive infrared (NDIR) CO2 sensor offering accurate carbon dioxide concentration measurements in a compact, low-power package. It provides both UART serial and PWM output, making it ideal for air quality monitors, HVAC systems, and IoT environmental sensing. With a measurement range of 0–5000 ppm and built-in temperature compensation, it delivers reliable readings for indoor and outdoor applications.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Method\u003c\/td\u003e\n\u003ctd\u003eNDIR (Non-Dispersive Infrared)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMeasurement Range\u003c\/td\u003e\n\u003ctd\u003e0–5000 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAccuracy\u003c\/td\u003e\n\u003ctd\u003e±(50 ppm + 5% of reading)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput\u003c\/td\u003e\n\u003ctd\u003eUART (TTL 3.3V), PWM\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e4.5–5.5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eWarm-up Time\u003c\/td\u003e\n\u003ctd\u003e\u0026lt;3 minutes\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/arduino-co2-monitor-kit-mh-z19-sensor-oled-and-ventilation-alert\"\u003eDesktop CO2 monitor with OLED display\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-esp32-wifi-relay-controller\"\u003eSmart ventilation controller using relay and WiFi\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-classroom-air-quality-monitor-kit\"\u003eClassroom air quality logger with SD card\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-air-quality-index-dashboard\"\u003eIoT indoor air quality dashboard with MQTT\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThe MH-Z19E operates on 5V logic but includes a 3.3V regulator, allowing direct connection to 5V and 3.3V microcontrollers like Arduino Uno, ESP32, and Raspberry Pi. It uses a standard 4-pin header (VCC, GND, TX, RX) and communicates via UART at 9600 baud, making it easy to integrate with popular development boards.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, and TX\/RX to the microcontroller's RX\/TX respectively. For PWM mode, use the PWM pin. Ensure a stable power supply; spikes may affect accuracy. The sensor requires a few minutes of warm-up for optimal readings.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino Uno?\u003c\/summary\u003e\u003cp\u003eYes, connect the sensor's TX to Arduino pin 2 (SoftwareSerial RX) and RX to pin 3 (TX), or use hardware serial (RX to RX, TX to TX with voltage level shifting if needed).\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the lifespan of the NDIR sensor?\u003c\/summary\u003e\u003cp\u003eThe MH-Z19E has a long operational life of over 5 years under normal indoor conditions, as NDIR sensors have no consumable parts.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes it require calibration?\u003c\/summary\u003e\u003cp\u003eThe sensor comes pre-calibrated, but for high-accuracy applications, manual calibration using fresh air (400 ppm) is recommended periodically.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53444983685485,"sku":"CDN-0566","price":1810.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/winsen-mh-z19e-ndir-co2-sensor-air-quality-monitor-1718871.jpg?v=1790779987"},{"product_id":"mq-135-air-quality-gas-sensor-module-compoden","title":"MQ-135 Air Quality Gas Sensor Module | Compoden","description":"\u003ch1\u003eMQ-135 Air Quality Gas Sensor Module — Detects NH3, Benzene, Smoke, CO2\u003c\/h1\u003e\n\n\u003cp\u003eThe MQ-135 is a semiconductor gas sensor module designed to detect a wide range of air pollutants including ammonia, benzene, alcohol, smoke, and CO2. It provides both analog and digital outputs, making it ideal for DIY air quality monitors and alarm systems. With a fast response time and high sensitivity, this sensor is a reliable choice for indoor environment sensing.\u003c\/p\u003e\u003cp\u003eA sensor for learning projects; not a certified air-quality or gas detector.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Gases\u003c\/td\u003e\n\u003ctd\u003eAmmonia, Benzene, Smoke, CO2, Alcohol, etc.\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eHeater Power Consumption\u003c\/td\u003e\n\u003ctd\u003e\u0026lt;800mW\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e10–1000 ppm (gas-dependent)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog (0–5V) and Digital (TTL threshold)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePreheat Time\u003c\/td\u003e\n\u003ctd\u003e20–60 seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003e\n\u003cstrong\u003eIndoor Air Quality Monitor:\u003c\/strong\u003e Interface with an ESP8266 to send real-time pollution data to a cloud dashboard.\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSmoke-reading demo:\u003c\/strong\u003e show when the reading passes a threshold you set, with an LED.\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-industrial-gas-leak-detector-kit\"\u003e\n\u003cstrong\u003eAmmonia reading logger:\u003c\/strong\u003e log relative ammonia readings in an experiment.\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePortable Pollution Tester:\u003c\/strong\u003e Combine with an OLED display and battery for handheld outdoor air quality checks.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThe MQ-135 module operates at 5V logic, so it works directly with Arduino boards, ESP32, and Raspberry Pi (via an external ADC if using analog). Most 5V microcontrollers can read the analog output with a simple analogRead(). For 3.3V systems like Raspberry Pi Pico, use a logic level converter for the digital pin.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, AOUT to an analog input pin (e.g., A0 on Arduino), and DOUT to a digital pin if you need a simple threshold alarm. The sensor requires preheating for 20–60 seconds before readings stabilize. The digital output goes LOW when the gas concentration exceeds the potentiometer-set threshold.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eAbsolutely. Connect AOUT to any analog pin and read values with analogRead(). The digital pin can be used for simple threshold alerts.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan it measure precise CO2 levels?\u003c\/summary\u003e\u003cp\u003eThe MQ-135 is not selective; it responds to multiple gases. For accurate CO2 measurement, consider a dedicated NDIR sensor. However, it can detect relative changes in air quality.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I calibrate it?\u003c\/summary\u003e\u003cp\u003ePreheat the sensor for at least 24 hours initially. Then, in clean air, read the analog value as baseline. For gas-specific calibration, use a known concentration and adjust your code accordingly.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445024285037,"sku":"CDN-0769","price":110.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-135-air-quality-gas-sensor-module-compoden-2833204.jpg?v=1790779868"},{"product_id":"mq-3-alcohol-gas-sensor-module-for-breath-analyzer-projects","title":"MQ-3 Alcohol Gas Sensor Module for Arduino Projects","description":"\u003ch1\u003eMQ-3 Alcohol Gas Sensor Module – For Alcohol Vapour Projects\u003c\/h1\u003e\u003cp\u003eThe MQ-3 gas sensor module detects alcohol vapors with high sensitivity and fast response. It is used in alcohol-vapour detection learning projects (it is not a calibrated breathalyser and must not be used to judge fitness to drive), alcohol detection systems, and environmental monitoring. The module provides a convenient analog output that can be read by microcontrollers like Arduino.\u003c\/p\u003e\u003cp\u003eA sensor for learning projects; not a breathalyser and not for legal, medical or driving decisions.\u003c\/p\u003e\u003ch2\u003eKey Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eDetection Gas\u003c\/td\u003e\n\u003ctd\u003eAlcohol (Ethanol)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e0.05 – 10 mg\/L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog (0–5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003eApprox. 32 x 22 x 27 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeating Resistance\u003c\/td\u003e\n\u003ctd\u003e33Ω ± 10%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDIY breathalyzer with LCD display\u003c\/li\u003e\n\u003cli\u003eAlcohol detection alarm for vehicles\u003c\/li\u003e\n\u003cli\u003ePortable alcohol tester with microcontroller\u003c\/li\u003e\n\u003cli\u003eSmart IoT alcohol monitoring system\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility\u003c\/h2\u003e\u003cp\u003eWorks with any microcontroller that supports analog input, such as Arduino Uno, ESP32, ESP8266, and Raspberry Pi. Operates at 5V logic level, but can be used with 3.3V boards by using a level shifter for analog output.\u003c\/p\u003e\u003ch2\u003eWiring Notes\u003c\/h2\u003e\u003cp\u003eConnect VCC to 5V, GND to ground, and AOUT to an analog input pin. Allow a preheat time of about 1-2 minutes for stable readings. Use the on-board potentiometer to adjust the threshold for digital output (DOUT) if needed.\u003c\/p\u003e\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, the MQ-3 sensor module works directly with Arduino boards. Connect the analog output to any analog pin and power with 5V from the Arduino.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eCan it detect other gases like smoke?\u003c\/summary\u003e\u003cp\u003eThe MQ-3 has high selectivity for alcohol and low sensitivity to smoke and gasoline, making it ideal for alcohol-specific detection.\u003c\/p\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat is the preheat time required?\u003c\/summary\u003e\u003cp\u003eThe sensor requires about 1-2 minutes of preheating to give stable readings. This is normal for metal oxide semiconductor sensors.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445025497453,"sku":"CDN-0779","price":120.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-3-alcohol-gas-sensor-module-for-breath-analyzer-projects-5011915.jpg?v=1790779866"},{"product_id":"mq-5-methanelpg-gas-sensor-module-detect-methane-lpg-natural-gas","title":"MQ-5 Methane\/LPG Gas Sensor Module - Senses Methane, LPG, Natural Gas","description":"\u003ch1\u003eMQ-5 Methane\/LPG Gas Sensor Module\u003c\/h1\u003e\n\u003cp\u003eThe MQ-5 gas sensor module detects methane, LPG, and natural gas concentrations in the air. It provides an analog output that rises with gas concentration, for learning projects and data logging. It is not a certified gas detector. Its simple interface works with microcontrollers such as Arduino and Raspberry Pi.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eGas Detected\u003c\/td\u003e\n\u003ctd\u003eMethane (CH4), LPG, Natural Gas\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e300 – 10,000 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Signal\u003c\/td\u003e\n\u003ctd\u003eAnalog voltage (0-5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eHeating Resistance\u003c\/td\u003e\n\u003ctd\u003e33Ω ±5% at room temperature\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eLoad Resistance\u003c\/td\u003e\n\u003ctd\u003e10KΩ (adjustable via potentiometer)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/arduino-gas-leak-alarm-kit-mq-2-sensor-led-and-buzzer-for-kitchen-safety\"\u003eGas reading display with an LED threshold indicator\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eSmart kitchen safety system with IoT notifications (ESP8266\/ESP32)\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003ePortable air quality monitor with LCD display\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eMethane reading logger for a biogas experiment\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eCompatible with any 5V microcontroller board, including Arduino Uno, Nano, Mega, and Raspberry Pi (external ADC required). It operates on 5V logic, so the analog output can be read directly by 5V ADC pins. For 3.3V systems like Raspberry Pi Pico, use a voltage divider or level shifter.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, and AO (analog out) to an analog input pin. The MQ-5 draws about 200mA during heating, so use an external power source if powering from a board’s 5V regulator. Allow the sensor to preheat for at least 24 hours before the first use for accurate readings.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, the MQ-5 module works with any Arduino board. Connect the AO pin to an analog input and read the voltage. Many example sketches are readily available in the Arduino community.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes this module require calibration?\u003c\/summary\u003e\u003cp\u003eThe module comes pre-calibrated for LPG\/methane detection, but you can adjust the onboard potentiometer to change sensitivity. For accurate ppm readings, perform a two-point calibration using known gas concentrations.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the warm-up time?\u003c\/summary\u003e\u003cp\u003eAfter initial 24-hour burn-in, the sensor stabilizes within a minute of power-on. For precise measurements, allow 2-3 minutes of heating after each power cycle.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445107614061,"sku":"CDN-0376","price":110.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-5-methanelpg-gas-sensor-module-detect-methane-lpg-natural-gas-6262506.jpg?v=1790779507"},{"product_id":"mq-7-carbon-monoxide-gas-sensor-module-compoden-india","title":"MQ-7 Carbon Monoxide Gas Sensor Module - Compoden India","description":"\u003ch1\u003eMQ-7 Gas Sensor Module for Carbon Monoxide\u003c\/h1\u003e\n\u003cp\u003eThe MQ-7 gas sensor module is designed to detect carbon monoxide (CO) concentrations in the air. It is used in air-quality learning projects and data logging. It is not a certified CO detector. The module provides an analog output proportional to gas concentration, making it easy to integrate with microcontrollers.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Gas\u003c\/td\u003e\n\u003ctd\u003eCarbon monoxide (CO)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e20 – 2000 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eHeater Resistance\u003c\/td\u003e\n\u003ctd\u003e33 Ω ±5%\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePreheat Time\u003c\/td\u003e\n\u003ctd\u003e2 – 5 minutes (cycle)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog voltage (0 – 5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eCarbon monoxide reading display with an LED threshold indicator\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003ePortable air quality monitor with LCD display\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003eIoT gas-reading logger with notifications\u003c\/li\u003e\n  \u003cli\u003eSmart ventilation controller for enclosed spaces\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThis module operates at 5V, making it directly compatible with Arduino Uno, Nano, and Mega boards. For 3.3V systems like ESP32 or Raspberry Pi, use a level shifter or voltage divider on the analog output. It pairs well with LCD displays, buzzers, and relay modules for alert systems.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, and AOUT to an analog input pin. The module draws up to 350 mW during heating cycles; ensure your power supply can handle the load. For best accuracy, allow the sensor to preheat for 2–5 minutes before taking measurements. Avoid exposing the sensor to silicon vapors or corrosive gases to prolong lifespan.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, the MQ-7 module works directly with 5V Arduino boards like Uno and Nano. Connect AOUT to any analog pin to read CO levels.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow long does the sensor need to warm up?\u003c\/summary\u003e\u003cp\u003eInitial preheating takes 2–5 minutes for stable readings. For precise applications, allow 48 hours of continuous operation for complete stabilization.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan this sensor detect other gases?\u003c\/summary\u003e\u003cp\u003eIt is primarily sensitive to carbon monoxide but may show minor cross-sensitivity to hydrogen, methane, and alcohol vapors. For dedicated CO detection, use in controlled environments.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445108793709,"sku":"CDN-0394","price":120.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-7-carbon-monoxide-gas-sensor-module-compoden-india-8228377.jpg?v=1790779507"},{"product_id":"mq-9-gas-sensor-module-for-co-methane-lpg-detection","title":"MQ-9 Gas Sensor Module (CO, Methane, LPG) for Arduino","description":"\u003ch1\u003eMQ-9 Gas Sensor Module\u003c\/h1\u003e\n\u003cp\u003eThe MQ-9 gas sensor module senses carbon monoxide (CO), methane (CH₄), and liquefied petroleum gas (LPG). It’s widely used in air quality monitors and gas-sensing projects. The module outputs both analog voltage and a digital TTL signal, making it easy to integrate with microcontrollers for threshold-based alerts or concentration monitoring.\u003c\/p\u003e\u003cp\u003eA sensor for learning projects; not a certified gas or CO detector.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eGas Detected\u003c\/td\u003e\n\u003ctd\u003eCO, Methane, LPG\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Range\u003c\/td\u003e\n\u003ctd\u003e10–1000 ppm CO; 300–10,000 ppm Methane\/LPG\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5 V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog (0–5 V) and Digital (TTL)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePreheat Time\u003c\/td\u003e\n\u003ctd\u003e60–120 seconds (initial)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eCarbon monoxide sensing demo with LED indicators\u003c\/li\u003e\n  \u003cli\u003eMethane level sensing project for a kitchen or basement\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003ePortable air quality monitor with an LCD or OLED display\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-flood-and-gas-combined-home-alert\"\u003eSmart home gas alert system using an ESP8266 and cloud notifications\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eThe module works with any 5V microcontroller board including Arduino Uno, Nano, and Mega. It can also interface with 3.3V boards like ESP8266, ESP32, or Raspberry Pi when using a logic level shifter or voltage divider for the digital output. The analog output requires an ADC input on the host board.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, AOUT to an analog input (e.g., A0), and DOUT to a digital pin. The heater draws around 150 mA during the high-heat cycle, so avoid powering the module directly from a microcontroller’s 5V pin; use an external regulated supply.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino?\u003c\/summary\u003e\u003cp\u003eYes, the MQ-9 module operates at 5V and connects directly to any Arduino board. Use an analog pin to read gas concentration and a digital pin for the threshold output.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I calibrate the sensor?\u003c\/summary\u003e\u003cp\u003eAllow it to preheat for at least 2 minutes. For the digital output, adjust the onboard potentiometer until the threshold triggers in clean air. For analog accuracy, expose the sensor to a known concentration and map the voltage readings.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan it detect smoke from a fire?\u003c\/summary\u003e\u003cp\u003eThe sensor is optimized for CO, methane, and LPG, not particulate smoke. It may respond weakly to combustion gases present in smoke, but it is not a substitute for a dedicated smoke detector.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445108924781,"sku":"CDN-0398","price":110.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-9-gas-sensor-module-for-co-methane-lpg-detection-8196110.jpg?v=1790779507"},{"product_id":"mq-4-methane-gas-sensor-module-for-arduino-diy-compoden","title":"MQ-4 Methane Gas Sensor Module for Arduino \u0026 DIY - Compoden","description":"\u003ch1\u003eMQ-4 Methane Gas Sensor Module\u003c\/h1\u003e\n\u003cp\u003eThe MQ-4 is a semiconductor gas sensor module that responds to methane (CH4) and natural gas. It provides an analog output that rises with gas concentration, for learning projects and data logging. It is not a certified gas detector. Its high sensitivity to methane and quick response time allow for early detection of dangerous gas levels.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e5V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Gas\u003c\/td\u003e\n\u003ctd\u003eMethane (CH4)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eConcentration Range\u003c\/td\u003e\n\u003ctd\u003e200 - 10000 ppm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePreheat Time\u003c\/td\u003e\n\u003ctd\u003e~2 minutes\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Type\u003c\/td\u003e\n\u003ctd\u003eAnalog (0-5V)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eHeater Consumption\u003c\/td\u003e\n\u003ctd\u003e≤750mW\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eMethane reading display with an LED threshold indicator\u003c\/li\u003e\n  \u003cli\u003eIoT natural gas monitor using ESP8266\u003c\/li\u003e\n  \u003cli\u003eSmart kitchen safety system with exhaust fan control\u003c\/li\u003e\n  \u003cli\u003eArduino-based gas level data logger\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003cp\u003eCompatible with any microcontroller board that reads analog voltage, including Arduino Uno, Nano, Mega, ESP32, and Raspberry Pi (with ADC). Operates at 5V; for 3.3V logic, use a voltage divider or logic level converter. Pairs well with relay modules for automatic shutoff valves.\u003c\/p\u003e\n\n\u003ch2\u003eWiring Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V, GND to ground, and AOUT to an analog input pin. The sensor draws up to 150 mA during preheat; ensure the power supply can handle the surge. For stable readings, let it warm up for 2 minutes before use.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy from Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-7 days. If defective on arrival, replace within 7 days.\u003c\/p\u003e\n\n\u003cdetails\u003e\u003csummary\u003eIs this compatible with Arduino Uno?\u003c\/summary\u003e\u003cp\u003eYes, the MQ-4 outputs an analog voltage that can be read directly by any Arduino Uno analog pin. Use a 10K pull-down resistor on the output for cleaner readings.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow long does the sensor need to warm up?\u003c\/summary\u003e\u003cp\u003eThe MQ-4 requires a preheat time of about 2 minutes to stabilize readings. During this time, the heater element reaches its operating temperature.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan it detect LPG?\u003c\/summary\u003e\u003cp\u003eThe MQ-4 is primarily sensitive to methane, but it can also respond to LPG, though with lower sensitivity. For accurate LPG detection, consider the MQ-6 sensor.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdiv class=\"compoden-handoff\" style=\"margin-top:24px;padding:16px;background:#f0f4ff;border-left:4px solid #2B4D8F;border-radius:4px;\"\u003e\n  \u003cp style=\"margin:0 0 6px 0;font-weight:600;color:#1A3560;\"\u003e📦 Free Setup Handoff Document Included\u003c\/p\u003e\n  \u003cp style=\"margin:0;font-size:0.95em;color:#333;\"\u003eEvery Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.\u003c\/p\u003e\n\u003c\/div\u003e\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53445129634157,"sku":"CDN-0782","price":90.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mq-4-methane-gas-sensor-module-for-arduino-diy-compoden-8770162.jpg?v=1790779447"},{"product_id":"mh-z19b-co2-sensor-module-ndir-carbon-dioxide-sensor-uart","title":"MH-Z19B CO2 Sensor Module – NDIR Carbon Dioxide Sensor UART","description":"\u003ch1\u003eMH-Z19B NDIR CO2 Sensor Module – UART, 0-5000ppm\u003c\/h1\u003e\n\n\u003cp class=\"product-lede\"\u003eThe MH-Z19B is an NDIR (non-dispersive infrared) CO2 sensor module that measures carbon dioxide concentration from 0 to 5000 ppm and outputs data over a UART serial interface for air quality monitoring applications.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable class=\"specs-table\"\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDetection Gas\u003c\/td\u003e\n\u003ctd\u003eCarbon Dioxide (CO₂)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMeasurement Range\u003c\/td\u003e\n\u003ctd\u003e0–5000 ppm \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAccuracy\u003c\/td\u003e\n\u003ctd\u003e±(50 ppm + 5% of reading) \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Interface\u003c\/td\u003e\n\u003ctd\u003eUART TTL (3.3V\/5V compatible) \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePower Supply\u003c\/td\u003e\n\u003ctd\u003e4.5–5.5V DC \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAverage Current\u003c\/td\u003e\n\u003ctd\u003e\u0026lt;18 mA \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eWarm-up Time\u003c\/td\u003e\n\u003ctd\u003e3 minutes \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd\u003e0°C to 50°C \u003cspan class=\"confidence\"\u003e[Typical]\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCO₂ Monitor with LCD:\u003c\/strong\u003e Read CO₂ ppm on 16x2 I2C LCD with Arduino.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCloud CO₂ Dashboard:\u003c\/strong\u003e Stream sensor data to Blynk or ThingSpeak using ESP32.\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-sd-card-data-log-to-csv\"\u003e\n\u003cstrong\u003eData Logger:\u003c\/strong\u003e Log CO₂ levels to CSV with Python on Raspberry Pi.\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eClassroom CO₂ Study:\u003c\/strong\u003e Measure CO₂ change in a closed classroom for CBSE practicals or ATL lab.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSmart Exhaust Fan Controller:\u003c\/strong\u003e Auto‑activate fan when CO₂ exceeds threshold – ideal for B.Tech or Smart India Hackathon.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003ctable class=\"compat-table\"\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003ePlatform\u003c\/th\u003e\n\u003cth\u003eCompatible\u003c\/th\u003e\n\u003cth\u003eConnection\u003c\/th\u003e\n\u003cth\u003eLibrary \/ Method\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Uno R3\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→Pin 0, RX→Pin 1\u003c\/td\u003e\n\u003ctd\u003eMHZ19, SoftwareSerial\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Nano\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→D2, RX→D3\u003c\/td\u003e\n\u003ctd\u003eMHZ19, SoftwareSerial\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Mega 2560\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→RX1(19), RX→TX1(18)\u003c\/td\u003e\n\u003ctd\u003eMHZ19 (Serial1)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eESP8266 NodeMCU\u003c\/td\u003e\n\u003ctd\u003eYes with level shifting\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→D7 via divider, RX→D8\u003c\/td\u003e\n\u003ctd\u003eMHZ19, SoftwareSerial\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eESP32 Dev Board\u003c\/td\u003e\n\u003ctd\u003eYes with level shifting\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→any RX via divider, RX→any TX\u003c\/td\u003e\n\u003ctd\u003eMHZ19, HardwareSerial\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eRaspberry Pi Pico\u003c\/td\u003e\n\u003ctd\u003eYes with level shifting\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→UART RX via divider, RX→UART TX\u003c\/td\u003e\n\u003ctd\u003emhz19 (MicroPython)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 4 \/ 5\u003c\/td\u003e\n\u003ctd\u003eYes with level shifting\u003c\/td\u003e\n\u003ctd\u003eVCC 5V, TX→UART RX via divider, RX→UART TX\u003c\/td\u003e\n\u003ctd\u003emh‑z19, pyserial\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWiring and Interface Notes\u003c\/h2\u003e\n\u003cp\u003eConnect VCC to 5V and GND to ground; wire sensor TX to microcontroller RX and RX to TX. The sensor outputs 5V logic – on 3.3V boards use a voltage divider (e.g., 10kΩ\/20kΩ) on the TX line. Allow a 3‑minute warm‑up before readings stabilize; the module includes automatic baseline calibration (ABC) for long‑term accuracy.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"faq\"\u003e\n  \u003cdiv class=\"faq-item\"\u003e\n    \u003ch3\u003eHow does the MH-Z19B auto‑calibrate and can I disable it?\u003c\/h3\u003e\n    \u003cp\u003eThe sensor runs a 24‑hour automatic baseline calibration assuming 400 ppm ambient CO₂. You can disable ABC via a UART command when deploying in sealed or elevated‑CO₂ environments.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"faq-item\"\u003e\n    \u003ch3\u003eIs the MH-Z19B accurate enough for greenhouse CO₂ enrichment?\u003c\/h3\u003e\n    \u003cp\u003eYes, the typical accuracy of ±(50 ppm + 5% of reading) is sufficient for general greenhouse control. For precision horticultural or scientific research, consider a lab‑grade NDIR sensor.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53454858649965,"sku":"CDN-0980","price":1000.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/mh-z19b-co2-sensor-module-ndir-carbon-dioxide-sensor-uart-5446891.png?v=1790779328"},{"product_id":"pms5003-particulate-matter-sensor-pm25-air-quality-monitor","title":"PMS5003 Particulate Matter Sensor – PM2.5 Air Quality Monitor","description":"\u003ch1\u003ePMS5003 PM2.5 Laser Particle Sensor – Air Quality Monitor\u003c\/h1\u003e\n\n\u003cp class=\"product-lede\"\u003eThe PMS5003 is a laser-based particulate matter sensor that measures PM2.5 and PM10 concentrations in real time, outputting digital serial data with high accuracy and a long-life laser for air quality monitoring.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable class=\"specs-table\"\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eMeasurement Range\u003c\/td\u003e\n\u003ctd\u003e0.3–1.0, 1.0–2.5, 2.5–10 µm; PM2.5: 0–999 µg\/m³\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOutput Signal\u003c\/td\u003e\n\u003ctd\u003eUART serial (9600 bps default, 3.3V TTL)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePower Supply\u003c\/td\u003e\n\u003ctd\u003e5 V DC, typical current \u0026lt;100 mA\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eLaser Source\u003c\/td\u003e\n\u003ctd\u003eClass 1 laser, lifetime \u0026gt;8000 hours\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eResponse Time\u003c\/td\u003e\n\u003ctd\u003e\u0026lt;1 second\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eAccuracy\u003c\/td\u003e\n\u003ctd\u003e±10% for PM2.5 under standard conditions\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd\u003e-20 to +60 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e50 × 38 × 21 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhat You Can Build With This\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/pm2-5-air-quality-monitor-kit\"\u003e\n\u003cstrong\u003eArduino Air Quality Monitor:\u003c\/strong\u003e Display real‑time PM2.5 readings on a 16×2 LCD with an Arduino Uno and a simple SoftwareSerial sketch.\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003ca href=\"\/products\/kit-air-quality-index-dashboard\"\u003e\n\u003cstrong\u003eESP32 IoT Dashboard:\u003c\/strong\u003e Stream particulate data over Wi‑Fi to Blynk or ThingSpeak for a remote air quality dashboard using an ESP32.\u003c\/a\u003e\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRaspberry Pi Logger:\u003c\/strong\u003e Connect via UART to a Raspberry Pi, log PM2.5 values to InfluxDB, and visualise trends in Grafana.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCBSE Physics Practical:\u003c\/strong\u003e Measure indoor and outdoor particulate matter as part of an environmental monitoring project or ATL lab activity.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSmart City Air Alert:\u003c\/strong\u003e Build a multi‑node pollution mapping system with LoRa or cellular backhaul for a B.Tech final year project or Smart India Hackathon entry.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003ctable class=\"compat-table\"\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003ePlatform\u003c\/th\u003e\n\u003cth\u003eCompatible\u003c\/th\u003e\n\u003cth\u003eConnection\u003c\/th\u003e\n\u003cth\u003eLibrary \/ Method\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Uno R3\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via D2 (RX), D3 (TX) (SoftwareSerial)\u003c\/td\u003e\n\u003ctd\u003ePMS5003 Arduino library\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Nano\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via D2 (RX), D3 (TX) (SoftwareSerial)\u003c\/td\u003e\n\u003ctd\u003ePMS5003 Arduino library\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Mega 2560\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via hardware Serial1 (RX1, TX1)\u003c\/td\u003e\n\u003ctd\u003ePMS5003 Arduino library\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eESP8266 NodeMCU\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via GPIO (RXD2, TXD2 or SoftwareSerial)\u003c\/td\u003e\n\u003ctd\u003ePMS5003 Arduino library\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eESP32 Dev Board\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via any free GPIO (HardwareSerial)\u003c\/td\u003e\n\u003ctd\u003ePMS5003 Arduino library or ESP-IDF UART\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eRaspberry Pi Pico\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUART via GP0 (TX) \/ GP1 (RX)\u003c\/td\u003e\n\u003ctd\u003eMicroPython UART module\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eRaspberry Pi 4 \/ 5\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003ctd\u003eUSB‑UART adapter or GPIO UART\u003c\/td\u003e\n\u003ctd\u003ePython pyserial library\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWiring and Interface Notes\u003c\/h2\u003e\n\u003cp\u003eConnect the sensor’s TX pin to the microcontroller RX and RX to TX; a level shifter is recommended because the PMS5003 uses 3.3V logic while many Arduino boards operate at 5V. Power the sensor with 5V (or 3.3V if available) and always share a common ground. The default UART baud rate is 9600, and the sensor outputs a 32‑byte data packet – use a pre‑built library to parse PM2.5, PM10, and particle count values reliably.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"faq\"\u003e\n  \u003cdiv class=\"faq-item\"\u003e\n    \u003ch3\u003eDoes the PMS5003 output PM1.0 and PM10 values?\u003c\/h3\u003e\n    \u003cp\u003eThe sensor primarily measures PM2.5 concentration, but it also calculates PM1.0 and PM10 based on particle size distribution. You can read these values from the serial data frame using the standard protocol.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"faq-item\"\u003e\n    \u003ch3\u003eCan this sensor be used outdoors continuously?\u003c\/h3\u003e\n    \u003cp\u003eYes, but it is not waterproof. For outdoor deployments, place it inside a ventilated weatherproof enclosure and clean the laser diode periodically to prevent dust build‑up affecting accuracy.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e\n\n","brand":"Compoden","offers":[{"title":"Default Title","offer_id":53454858682733,"sku":"CDN-0981","price":2330.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/pms5003-particulate-matter-sensor-pm25-air-quality-monitor-7921486.jpg?v=1790779327"}],"url":"https:\/\/compoden.com\/collections\/gas-air-quality-sensors.oembed","provider":"Compoden","version":"1.0","type":"link"}