{"product_id":"xd-digital-tachometer-with-hall-sensor-dc-motor-speed-meter","title":"XD Digital Tachometer with Hall Sensor, DC Motor Speed Meter, Digital Display RPM Gauge for Motor","description":"\u003ch1\u003ehall sensor tachometer,motor speed meter\u003c\/h1\u003e\n\u003ch1\u003eProduct Description\u003c\/h1\u003e\n\u003ch2\u003eOverview\u003c\/h2\u003e\n\u003cp\u003eThis high-precision digital tachometer adopts Hall sensor technology to measure motor rotational speed. It features 3 LED display color options, stable reading with ±0.1% accuracy, widely used for DC motor \/ 马达 speed monitoring. Matching Hall switch model: NJK-5002C, NPN normally open type.\u003c\/p\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eProduct Name: Digital Tachometer\u003c\/li\u003e\n\u003cli\u003ePower Supply: DC 8-24V, 40mA\u003c\/li\u003e\n\u003cli\u003eDisplay: 0.56\" LED, 4-digit reading\u003c\/li\u003e\n\u003cli\u003eMeasuring Range: 10 ~ 9999 RPM\u003c\/li\u003e\n\u003cli\u003eAccuracy: ±0.1% of reading ±1 digit\u003c\/li\u003e\n\u003cli\u003eDimension: 80\u003cem\u003e40\u003c\/em\u003e32mm\u003c\/li\u003e\n\u003cli\u003eWeight: approx. 80g\u003c\/li\u003e\n\u003cli\u003eOver-range indication: \"LLLL\" for below range; \"HHHH\" for over range\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003ePackage Options\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eGreen (Motor Tachometer)\u003c\/li\u003e\n\u003cli\u003eBlue (Motor Tachometer)\u003c\/li\u003e\n\u003cli\u003eRed (Motor Tachometer, Recommended)\u003c\/li\u003e\n\u003cli\u003eTachometer Mount Bracket\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003ePrecautions\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eAvoid strong electromagnetic interference. Use shielded or twisted pair cables for signal wiring. Do not route signal wires together with high-power cables to prevent interference.\u003c\/li\u003e\n\u003cli\u003eThe matched Hall switch is 12mm diameter NPN normally open sensor. You can replace it with other NPN NO sensors.\u003c\/li\u003e\n\u003cli\u003eFirmly fix Hall switch and magnet. The installation gap between Hall sensor and magnet must be within 10mm. Vibration will cause unstable or jumping readings.\u003c\/li\u003e\n\u003cli\u003eDo not mount magnet on ferrous metal, it will interfere measurement. Magnet has polarity; reversed installation leads to no reading.\u003c\/li\u003e\n\u003cli\u003eMechanical \/ micro switches are NOT recommended due to short service life and miscount risk. Magnetic Hall sensor is strongly recommended.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003ch3\u003eTroubleshooting\u003c\/h3\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eIssue\u003c\/th\u003e\n\u003cth\u003eCause\u003c\/th\u003e\n\u003cth\u003eSolution\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eShows \"LLLL\"\u003c\/td\u003e\n\u003ctd\u003e1. Hall sensor not connected2. No magnet detected \/ too large gap \/ misaligned3. Actual speed too low4. Defective Hall switch\u003c\/td\u003e\n\u003ctd\u003eInstall Hall sensor \u0026amp; magnet correctly; test within measuring range; replace Hall switch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShows \"HHHH\"\u003c\/td\u003e\n\u003ctd\u003e1. EMI interference (e.g. inverter)2. Actual speed exceeds max range\u003c\/td\u003e\n\u003ctd\u003eUse shielded anti-interference Hall sensor, connect shield wire to Hall blue wire; test within range\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eJumping \/ inaccurate reading\u003c\/td\u003e\n\u003ctd\u003e1. EMI interference (inverter)2. Eccentric rotating disc3. Loosely fixed sensor\/magnet\u003c\/td\u003e\n\u003ctd\u003eUse shielded Hall sensor; replace with concentric disc; firmly secure sensor and magnet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch1\u003e\u003c\/h1\u003e\n\u003ch1\u003eAttribute Table\u003c\/h1\u003e\n\u003cpre\u003e\u003ccode\u003eproduct_name: XD Digital Tachometer with Hall Sensor\nproduct_type: Industrial Sensor \u0026amp; Meter\nmaterial: Plastic + Metal\ndisplay_type: 4-digit LED digital display\nled_color: Red \/ Green \/ Blue\nsensor_type: Hall Effect Sensor\nhall_model: NJK-5002C\noutput_type: NPN Normally Open\noperating_voltage: DC 8V-24V\ncurrent_draw: 40mA\nmeasuring_range: 10~9999 RPM\nmeasurement_accuracy: ±0.1% reading ±1 digit\nproduct_size: 80*40*32mm\nweight: 80g\nmounting: Optional metal bracket\napplication: DC motor, motor speed measurement, RPM monitoring\n\u003c\/code\u003e\u003c\/pre\u003e\n\u003ch1\u003eFAQ\u003c\/h1\u003e\n\u003cp\u003e\u003cstrong\u003eQ1: What sensor does this tachometer use?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: It works with NJK-5002C Hall effect sensor (12mm NPN normally open). Other NPN NO hall sensors are compatible.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ2: What power supply do I need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: DC 8V to 24V, working current 40mA.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ3: What does \"LLLL\" \/ \"HHHH\" mean on screen?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: LLLL = speed below measuring minimum limit. HHHH = speed over maximum measuring range. It can also be caused by bad wiring or sensor misalignment.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ4: What is the maximum gap between hall sensor and magnet?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: Keep distance ≤10mm. Magnet must be properly polarized, cannot attach to iron metal.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ5: Can I use mechanical micro switch instead of hall sensor?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: Not recommended. Mechanical switches have short lifespan and miscount. Hall magnetic sensor is preferred.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ6: Will inverter affect reading?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: Yes, inverters cause electromagnetic interference. Use shielded anti-interference hall sensor and shielded twisted cable.\u003c\/p\u003e","brand":"electrical center b2c","offers":[{"title":"Red","offer_id":50760471969985,"sku":"Red Digital Tachometer with Hall Sensor","price":23.59,"currency_code":"USD","in_stock":true},{"title":"Blue","offer_id":50760472002753,"sku":"Blue Digital Tachometer with Hall Sensor","price":23.59,"currency_code":"USD","in_stock":true},{"title":"Green","offer_id":50760472035521,"sku":"Green Digital Tachometer with Hall Sensor","price":23.59,"currency_code":"USD","in_stock":true},{"title":"Meter Bracket","offer_id":50760472068289,"sku":"Meter Bracket Digital Tachometer with Hall Sensor","price":6.7,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0583\/0872\/2881\/files\/imgi_21_O1CN01NPOtxJ1fYIS7sCbwx__122984018_jpg.webp?v=1792131190","url":"https:\/\/www.electric-b2c.com\/ar\/products\/xd-digital-tachometer-with-hall-sensor-dc-motor-speed-meter","provider":"electrical center b2c","version":"1.0","type":"link"}