Product Introduction
The KH.WQX Bubble Water Level Gauge is a high-precision water level sensor independently developed and manufactured by KEHAO. It measures the water level by introducing compressed air from a piston pump into the measuring tube and bubble chamber. The static pressure in the tube is directly proportional to the water level above the bubble chamber. By alternately measuring atmospheric and bubble pressures, the instrument calculates the actual water level with exceptional accuracy and stability.

Features
• Industry-leading innovation – KEHAO is the first to use imported three-way solenoid valves to eliminate “zero drift.” The intelligent control unit drives the solenoid valve to switch periodically, automatically recalibrating the zero point and ensuring long-term accuracy.
• Patented automatic zero calibration – This invention effectively corrects zero drift of the differential pressure sensor, significantly improving measurement stability and reliability.
• Durable mechanical design – The crank-connecting rod and plug-type cylinder design greatly reduce piston seal friction, extending the instrument’s service life.
• Verified precision – Test reports confirm Level 1 accuracy within the 0–10 m measurement range, meeting national standard requirements.

Application Scenarios
Ideal for continuous monitoring of reservoirs, rivers, streams, channels, hydrological and oceanographic stations, pumping stations, and hydropower plants.

Technical Parameters
• Power supply: 9.6–30 VDC
• Standby current: ≤1 mA
• Average current: ≤10 mA (1 min interval, RS485 or SDI-12 output)
• Measuring range: 20 m / 30 m / 40 m / 50 m / 60 m optional, 70–100 m customizable
• Resolution: 1 mm
• Measurement accuracy: 0.03% FS
• Compensation: Temperature and latitude compensation supported
• Max water level change rate: 60 cm/min
• Measurement interval: Configurable 1 min–24 h (default 5 min)
• Communication: RS485 or SDI-12
• Analog output: 4–20 mA
• Measuring tube: inner φ3 / outer φ8
• Temperature sensor: NTC 103 (optional)
• Medium: Water (rivers, lakes, groundwater, etc.), special liquids customizable
• Working temperature: -20 to 80°C
• Storage temperature: -40 to 85°C
• Ambient humidity: ≤95%