1PC 4-Digit LED Tachometer RPM Speed Meter with Hall Proximity Switch Sensor NPN Product Features: - and high quality - 4-digit 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 - Can be used for voltage and current measurement; compatible with external sensors for measuring temperature, pressure, displacement, and other physical quantities - Saves setting parameters when powered off - Suitable for measuring the speed of various types of motors - Over-range indication: displays "1" or "-1" on the thousands digit while the last three digits are 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: Approximately 80 x 25 x 40mm (L x W x H) - Installation Size: Approximately 76 x 39mm - LED Color: Red/Blue - Detected Object: Magnet - Detection Range: 1–10mm - Proximity Output Current: 20mA (for sensor) - Operating Temperature: -10°C to 60°C - Sensor Dimensions: 60 x 10mm - Sensor Wire Length: 1.2 meters - Magnet Size: 10 x 2mm Package Includes: - 1 x LED Tachometer - 1 x NPN Hall Proximity Sensor