{"product_id":"kit-led-tester-and-current-limiter","title":"LED Tester and Current Limiter Kit with Arduino Uno","description":"\u003ch1\u003eBuild Your Own Precision LED Tester and Current Limiter with Arduino Uno\u003c\/h1\u003e\n\u003cp class=\"value-summary\"\u003eEvery part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.\u003c\/p\u003e\n\u003cdiv class=\"specs-strip\"\u003e\n  \u003cspan\u003e\u003cstrong\u003eDifficulty:\u003c\/strong\u003e Beginner\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eBuild Time:\u003c\/strong\u003e 1-2 hrs\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eAge:\u003c\/strong\u003e 5-15\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eSkill:\u003c\/strong\u003e Measuring and controlling LED current safely\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cp\u003eStop guessing whether your LEDs are working or risk burning them out. This kit lets you build a dedicated test instrument that dials in any current from 1mA to 30mA with a knob, displays the actual current flowing through the LED via the ACS712 sensor, and shows the LED's forward voltage (Vf) on a bright 16x2 LCD. Once built, it becomes a permanent bench tool for sorting, testing, and matching LEDs in any maker’s lab.\u003c\/p\u003e\n\u003ch2\u003eWhat You'll Build\u003c\/h2\u003e\n\u003cp\u003eYou’ll assemble a self-contained LED characterisation station: an Arduino Uno reads the ACS712 current sensor and drives a standard 16x2 LCD through an I2C backpack. A potentiometer lets you set a precise current limit, and the IRF540N MOSFET regulates current without flicker. Plug in an LED, turn the knob, and instantly know its Vf and the exact milliamps it’s drawing — no multimeter needed. It’s your personal LED sorting jig.\u003c\/p\u003e\n\u003ch2\u003eWhat You'll Learn\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eHow to use a potentiometer as an adjustable control for current limiting\u003c\/li\u003e\n  \u003cli\u003eReading current values from an ACS712 Hall-effect sensor and displaying them on an LCD\u003c\/li\u003e\n  \u003cli\u003eMeasuring forward voltage of LEDs and understanding Vf variation across colours and types\u003c\/li\u003e\n  \u003cli\u003eMOSFET-based constant current control — a practical analog circuit used in power electronics\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eKit Contents\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eComponent\u003c\/th\u003e\n\u003cth\u003eQuantity\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\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eACS712 5A\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eIRF540N MOSFET\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e16x2 LCD\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eI2C Backpack\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e10kΩ Potentiometer\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100Ω Gate Resistors\u003c\/td\u003e\n\u003ctd\u003e3\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e400-pt Breadboard\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eM-M Wires\u003c\/td\u003e\n\u003ctd\u003e20\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e9V Battery Snap\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eWhy Buy This Kit Instead of Sourcing Parts Separately\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eFactor\u003c\/th\u003e\n\u003cth\u003eSourcing Separately\u003c\/th\u003e\n\u003cth\u003eCompoden Kit\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCompatibility checks\u003c\/td\u003e\n\u003ctd\u003eYou verify every part\u003c\/td\u003e\n\u003ctd\u003ePre-tested as a system\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eBuild support\u003c\/td\u003e\n\u003ctd\u003eForums and scattered tutorials\u003c\/td\u003e\n\u003ctd\u003eAI companion trained on this exact project\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTime to first working build\u003c\/td\u003e\n\u003ctd\u003eDays of debugging\u003c\/td\u003e\n\u003ctd\u003eHours, with step-by-step guidance\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eShipping coordination\u003c\/td\u003e\n\u003ctd\u003eMultiple sellers, multiple delays\u003c\/td\u003e\n\u003ctd\u003eOne shipment from Bengaluru in 3-5 days\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch2\u003eWho This Kit Is For\u003c\/h2\u003e\n\u003cp\u003ePerfect for CBSE Class 11–12 students exploring practical physics and electronics, B.Tech ECE\/EEE freshers building their first measurement tools, and ATL tinkering lab facilitators who need a reusable demo instrument. The 5–15 age range makes it an ideal parent-child STEM project; everything runs off a 9V battery, so it’s safe and portable. Makers from IITs, NITs, and VIT will find it a handy bench companion for testing salvaged or bulk LEDs.\u003c\/p\u003e\n\u003ch2\u003eBuilt and Backed by Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.\u003c\/p\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat if I get stuck during the build?\u003c\/summary\u003e\u003cp\u003eScan the QR code inside the box to start a conversation with the AI build companion. It understands every wire and code line for this specific kit. If you need a human, message us on WhatsApp — we reply within a few hours.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan this tester handle high-power LEDs like 1W or 3W?\u003c\/summary\u003e\u003cp\u003eThe default current range is 1–30mA, designed for standard 3mm and 5mm indicator LEDs. You can modify the circuit for higher currents, but the kit components are optimised for safe learning and everyday lab use.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I connect the LED to be tested?\u003c\/summary\u003e\u003cp\u003eThe breadboard includes marked test points. Just insert the LED into the dedicated socket strips — the polarity is clearly labelled through the build guide. No soldering required.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes this kit need a computer for programming?\u003c\/summary\u003e\u003cp\u003eYes, you'll need a computer with the Arduino IDE (free) to upload the provided code. The AI companion walks you through installation and upload in under 10 minutes.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003cdiv class=\"kit-description\"\u003e\n  \u003cp\u003ePotentiometer sets test current from 1mA to 30mA. ACS712 measures actual LED current. LCD shows Vf.\u003c\/p\u003e\n  \u003ch4\u003eWhat's in this kit\u003c\/h4\u003e\n  \u003cul\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/uno-r3-ch340g-atmega328p-board-arduino-compatible\"\u003eArduino Uno R3\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/acs712-5a-current-sensor-module-precise-hall-effect-measurement\"\u003eACS712 5A\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/irf540n-mosfet-100v-33a-n-channel-power-transistor-compoden\"\u003eIRF540N MOSFET\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/16x2-lcd-display-module-16x2-character-blue-backlight\"\u003e16x2 LCD\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/i2c-backpack-pcf8574-i2c-adapter-for-lcd-displays\"\u003eI2C Backpack\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/ntc-thermistor-temperature-sensor-module-3-pin-10k%CF%89\"\u003e10kΩ Potentiometer\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e100Ω Gate Resistors x3\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/breadboard-standard-bundle-830400-tie-points-for-prototyping\"\u003e400-pt Breadboard\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003eM-M Wires x20\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/9v-battery-snap-connector-with-15cm-wires-compoden\"\u003e9V Battery Snap\u003c\/a\u003e\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is included in the LED Tester and Current Limiter Kit with Arduino Uno?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The LED Tester and Current Limiter Kit with Arduino Uno includes all components needed: Arduino Uno R3, ACS712 5A, IRF540N MOSFET, 16, I2C Backpack and more. Everything is pre-tested for compatibility and shipped from Bengaluru, India.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What skill level is required for the LED Tester and Current Limiter Kit with Arduino Uno?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"This kit is designed for Beginner level makers, suitable for ages 5-15. Potentiometer sets test current from 1mA to 30mA. ACS712 measures actual LED current. LCD shows Vf. Estimated build time is 1-2 hrs.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I buy the LED Tester and Current Limiter Kit with Arduino Uno online in India?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes, the LED Tester and Current Limiter Kit with Arduino Uno is available online at Compoden (compoden.in), India's AI-powered electronics and robotics store. Ships from Bengaluru in 1-5 business days across India.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"Product\",\n  \"name\": \"LED Tester and Current Limiter Kit with Arduino Uno\",\n  \"description\": \"Potentiometer sets test current from 1mA to 30mA. ACS712 measures actual LED current. LCD shows Vf.\",\n  \"sku\": \"CDN-KIT-2118\",\n  \"brand\": {\"@type\": \"Brand\", \"name\": \"Compoden\"},\n  \"offers\": {\n    \"@type\": \"Offer\",\n    \"url\": \"https:\/\/compoden.in\/products\/kit-led-tester-and-current-limiter\",\n    \"priceCurrency\": \"INR\",\n    \"price\": \"1280\",\n    \"availability\": \"https:\/\/schema.org\/InStock\",\n    \"seller\": {\"@type\": \"Organization\", \"name\": \"Compoden\"}\n  },\n  \"category\": \"Maker Tools \u0026 Instruments\"\n}\n\u003c\/script\u003e","brand":"Compoden","offers":[{"title":"Clone","offer_id":53469318021485,"sku":"CDN-KIT-2118-CL","price":1450.0,"currency_code":"INR","in_stock":true},{"title":"R3 Original","offer_id":53469318054253,"sku":"CDN-KIT-2118-R3","price":3720.0,"currency_code":"INR","in_stock":true},{"title":"R4 WiFi","offer_id":53469318087021,"sku":"CDN-KIT-2118-R4","price":3080.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/kit-led-tester-and-current-limiter.png?v=1781947723","url":"https:\/\/compoden.com\/products\/kit-led-tester-and-current-limiter","provider":"Compoden","version":"1.0","type":"link"}