The Three Core Functions of Liquid Level Sensors
Liquid level sensors act like "height gauges" for liquids, primarily working in three ways:
- Buoyancy Principle: A float rises and falls with the liquid level, actuating a reed switch, similar to a swimming pool's overflow alarm.
- Pressure Sensing: Liquid level is calculated by converting the hydrostatic pressure at the bottom; this method is commonly used in oil tankers.
- Wave Reflection Technology: Ultrasonic/radar waves reflect off the liquid surface, and the time difference is calculated to determine the height.
The Intelligent Evolution of Liquid Level Monitors
Modern liquid level monitors have evolved into versatile devices:
- Industrial-Grade Monitoring: Magnetostrictive sensors are used in chemical plants. Sensor accuracy up to ±0.5mm.
- Smart Home Version: Water tank monitor with Wi-Fi, allowing real-time water level monitoring via mobile phone.
- Special Environment Applications: Corrosion-resistant type for monitoring acid and alkali solutions; explosion-proof type for oil and gas storage tanks.
Selection Guide: Matching the sensor to your needs will maximize efficiency:
- Media Characteristics: Viscous liquids are suitable for capacitive sensors; pure liquids require optical sensors.
- Measuring Range: Ultrasonic sensors are preferred within 2 meters; radar sensors are used beyond 30 meters.
- Installation Requirements: Non-contact type for top mounting; float type for side mounting.