1PC 4-Digit LED Tachometer RPM Speed Meter with Hall Proximity Switch Sensor NPN Product Features: - and high quality - 4-digit LED display, clear and easy to read - Compact size, high performance, and fast response speed - Offers good stability, high accuracy, and strong anti-interference capability - Utilizes advanced A/D conversion chip, high-stability reference IC, and reliable chip components - Suitable for measuring voltage and current; can be used with external sensors to measure temperature, pressure, displacement, and other physical quantities - Saves settings when powered off - Ideal for measuring the speed of various types of motors - Over-range indication: displays 1 or -1 on the thousands digit, with the last three digits blank Product Specifications: - Display Type: LED - Voltage: DC 8-24V - Current: 30mA - Measurement Range: 10-9999 RPM - Accuracy: 0.1% - Clear Zero Time: Approximately 10 seconds - Display Refresh Rate: 3 times per second - Dimensions: 80 x 25 x 40mm (L x W x H) - Installation Size: 76 x 39mm - LED Color: Red or Blue - Detectable Object: Magnet - Detection Range: 1mm to 10mm - Proximity Output Current: 20mA (for sensor) - Operating Temperature: -10C to 60C - Sensor Dimensions: 60 x 10mm - Sensor Cable Length: 1.2 meters - Magnet Size: 10 x 2mm Package Includes: - 1 x LED Tachometer - 1 x NPN Hall Proximity Sensor