{"product_id":"fc-33-ir-slot-optical-speed-sensor-lm393-encoder-rpm","title":"IR Slot Optical Speed Sensor Module FC-33 LM393 - Encoder Disc RPM Counter for Arduino","description":"\u003ch2 style=\"text-align:center;\"\u003eIR Slot Optical Speed Sensor Module FC-33 \/ LM393 - Encoder Disc RPM and Position Counter\u003c\/h2\u003e\u003cp style=\"text-align:center;\"\u003eMeasure motor RPM, encoder disc position, and rotational speed with this compact slotted infrared optical sensor module. The FC-33 uses an IR photointerrupter (slotted optocoupler) paired with an LM393 comparator to deliver a clean digital pulse output every time an encoder disc or blade passes through the slot - making it ideal for speed measurement, position counting, and tachometer projects with Arduino and ESP32.\u003c\/p\u003e\u003cp style=\"text-align:center;\"\u003e\u003cimg src=\"https:\/\/sidekick.shopify.ai\/rails\/active_storage\/blobs\/redirect\/eyJfcmFpbHMiOnsiZGF0YSI6MzczNDkzNzY2NCwicHVyIjoiYmxvYl9pZCJ9fQ==--657fae6d757b52ee9698a6c86be0857853a6b843\/WhatsApp_Image_2026-09-14_at_7.52.30_PM_1.jpeg\" alt=\"FC-33 LM393 IR Slot Optical Speed Sensor Module with slotted infrared photointerrupter and 3-pin header on black PCB\" style=\"max-width:100%;height:auto;border-radius:8px;\"\u003e\u003c\/p\u003e\u003ch3\u003eKey Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eSlotted IR photointerrupter - detects encoder disc teeth or blades passing through the slot\u003c\/li\u003e\n\u003cli\u003eLM393 comparator IC - provides a clean, stable digital HIGH\/LOW output signal\u003c\/li\u003e\n\u003cli\u003eDigital output - directly readable by Arduino, ESP32, Raspberry Pi, and any microcontroller\u003c\/li\u003e\n\u003cli\u003eLED indicator - lights when the slot is clear (no obstruction), off when blocked\u003c\/li\u003e\n\u003cli\u003e3-pin header (VCC, GND, OUT) - standard 2.54mm pitch, breadboard and Dupont cable compatible\u003c\/li\u003e\n\u003cli\u003eCompact black PCB - easy to mount on motor shafts, wheels, and rotating assemblies\u003c\/li\u003e\n\u003cli\u003eCompatible with standard 20-slot encoder discs (sold separately)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e FC-33\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComparator IC:\u003c\/strong\u003e LM393\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSensor Type:\u003c\/strong\u003e Slotted IR photointerrupter (optocoupler)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupply Voltage:\u003c\/strong\u003e 3.3V - 5V DC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutput Type:\u003c\/strong\u003e Digital (HIGH \/ LOW)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutput Connector:\u003c\/strong\u003e 3-pin 2.54mm header (VCC, GND, OUT)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndicator:\u003c\/strong\u003e LED (lights when slot is unobstructed)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePCB Color:\u003c\/strong\u003e Black\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eHow It Works\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eAn IR LED and IR photodiode face each other across the slot gap\u003c\/li\u003e\n\u003cli\u003eWhen the slot is clear, IR light reaches the photodiode and output is HIGH\u003c\/li\u003e\n\u003cli\u003eWhen an encoder disc tooth or blade breaks the IR beam, output goes LOW\u003c\/li\u003e\n\u003cli\u003eThe LM393 comparator sharpens the transition for clean digital pulse counting\u003c\/li\u003e\n\u003cli\u003eCount pulses per second to calculate RPM using known disc slot count\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003ePerfect For\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMotor RPM and Speed Measurement with Encoder Disc\u003c\/li\u003e\n\u003cli\u003eArduino and ESP32 Tachometer Projects\u003c\/li\u003e\n\u003cli\u003eConveyor Belt and Wheel Speed Sensing\u003c\/li\u003e\n\u003cli\u003eRobotic Position and Revolution Counter\u003c\/li\u003e\n\u003cli\u003eLine Following Robot Wheel Odometry\u003c\/li\u003e\n\u003cli\u003eCNC and 3D Printer Encoder Feedback\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp style=\"text-align:center;\"\u003e\u003cstrong\u003eOrder now and add accurate digital speed and position sensing to your motor control or robotics project.\u003c\/strong\u003e\u003c\/p\u003e","brand":"Lahore Store","offers":[{"title":"Default Title","offer_id":56096954515529,"sku":"SEN-FC33-IR-SLOT-LM393","price":180.0,"currency_code":"PKR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0946\/9090\/2089\/files\/WhatsApp_Image_2026-09-14_at_7.52.30_PM_1.jpg?v=1789399895","url":"https:\/\/lahorestore.pk\/products\/fc-33-ir-slot-optical-speed-sensor-lm393-encoder-rpm","provider":"Lahore Store","version":"1.0","type":"link"}