Photoelectric Liquid Level Switch

WORKING PRINCIPLE

When the sensor is surrounded by air, the angle of incidence is greater than the critical angle and thus total refection occurs. Totally reflected light will be transmitted to the receiver. When the sensor is surrounded by liquid, due to the refractive index of the liquid and the sensor tip material, almost all light will penetrate the front of the sensor. Using this principle, the optical liquid level switch design is based on light, The receiver can detect and determine a light reflected or penetrated state, and determines the circuit output.

✅ Core Advantages

No mechanical wear: No moving parts, long service life (over one million cycles), maintenance-free.

Fast response: Millisecond-level response, no hysteresis, suitable for high-speed control applications.

Compact and easy to install: Supports top, side, or embedded mounting, adaptable to small water tanks and pipelines.

High adaptability: Unaffected by liquid density, viscosity, or conductivity; compatible with clean water, oils, chemical solvents, and more.

Hygienic and user-friendly: Easy to clean, ideal for applications with high cleanliness requirements such as food processing, medical devices, and home appliances.

📌 Typical Application Scenarios

Home Appliances: Water tank level control and dry-boil protection for coffee machines, water purifiers, dishwashers, and humidifiers.

Medical Devices: Infusion monitoring and reagent bottle liquid level detection (with high hygiene requirements).

Industrial Automation: Liquid level alarm and fixed-point control for chemical storage tanks, water treatment equipment, and beverage filling machines.

New Energy: Coolant level monitoring for battery pack liquid cooling systems and energy storage equipment.