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1. Product Features

BT-WQ-YD is an inductance-based salinity sensor that operates without electrodes. It utilizes a generator to produce an alternating magnetic field in the primary coil, which induces a current in the medium. The strength of this induced current depends on the ion concentration in the medium. The induced current then generates another magnetic field in the secondary coil. The receiver measures the induced current in the coil, thereby determining the salinity of the medium. Additionally, it is equipped with an internal temperature sensor for automatic temperature compensation, making it suitable for long-term online environmental monitoring.

2. Working Principle & Key Advantages

• Electrodeless Electromagnetic Induction: Generates an alternating magnetic field to induce a current in the medium, completely isolating the measurement electronics from the fluid.
• No Polarization & Maintenance-Free: Without physical metallic electrodes, it eliminates electrode polarization, fouling, and scale buildup, making it ideal for dirty, viscous, or easily precipitating solutions.
• Automatic Temperature Compensation (PT1000): Built-in internal PT1000 temperature sensor automatically corrects readings for temperature-induced salinity fluctuations.
• Rugged Submersible IP68 Housing: Compact dimensions for water depths up to 20 meters with a 3+ year sensor lifespan.
• Low Power & Anti-Interference: Low power consumption with complete electrical isolation and anti-interference circuit design.

3. Diameters

4. Industry Applications

1）Marine & Oceanographic Research 

Applications: Open-sea buoy stations, coastal water quality profiling, estuaries, and salt-water intrusion monitoring in tidal rivers.

Value: Electrodeless non-contact design resists marine biofouling and salt corrosion, delivering maintenance-free long-term offshore telemetry.

2）Marine Aquaculture & Mariculture (海水养殖与水产育苗)

Applications: High-density marine fish/shrimp farming ponds, recirculating aquaculture systems (RAS), and sea ranching.

Value: Monitors salinity levels to maintain precise osmotic balance for aquatic organisms, ensuring fast growth and lower mortality rates.

3）Industrial Wastewater & High-Salinity Brine Processing (工业高盐废水与浓咸水处理)

Applications: Chemical wastewater, zero liquid discharge (ZLD) systems, reverse osmosis (RO) desalination plants, and textile dyeing effluents.

Value: Handles highly corrosive, heavy, or scale-forming industrial effluents where standard metal electrode sensors quickly corrode or fail.

4）Pharmaceuticals & Biotechnology (医药化工与生物科技)

Applications: Fermentation broth salinity tracking, saline solution preparation, and bioprocess fluid monitoring.

Value: Complete electrical isolation ensures zero contamination of biological media and precise process control.

5. Specifications