blue-green algae sensor, online algae monitoring, fluorescence algae monitoring, Yexsensor, cyanobacteria online monitoring, water eutrophication monitoring, aquaculture water quality monitoring

YEX-S2-BGA-8S Online Blue-Green Algae Sensor

Selective Fluorescence Detection — Built-in Self-Cleaning Brush, Stable Algae Cell Concentration Output

Blue-green algae (cyanobacteria) blooms release algal toxins, threatening drinking water safety and ecological balance. Traditional algae monitoring relies on manual sampling and laboratory microscopy, which lacks timeliness and cannot provide continuous early warning. The YEX-S2-BGA-8S uses the fluorescence method, emitting monochromatic light at the characteristic absorption peak of cyanobacteria and detecting the emitted fluorescence intensity to selectively measure blue-green algae cell concentration in water. It features a built-in cleaning brush, supports RS-485 Modbus and optional 4-20mA output, making it suitable for long-term unattended online monitoring.

Three Core Advantages

• Fluorescence Selective Detection
  Utilizes the characteristic spectral absorption-emission properties of cyanobacteria to effectively distinguish them from other algae, providing more targeted measurement.

• Built-in Self-Cleaning Brush, Reduced Maintenance Frequency
  The measurement window is equipped with a cleaning brush that regularly removes biological attachment and dirt, ensuring long-term data stability.

• RS-485 Modbus / 4-20mA Dual Output Optional
  Standard industrial interface with optional analog output for quick integration into water quality monitoring platforms or PLC systems.

YEX-S2-BGA-8S Online Blue-Green Algae Sensor Product Value

The core challenges of online blue-green algae monitoring are: how to specifically detect cyanobacteria concentration among numerous phytoplankton, and how to prevent biofilm growth on the sensor window during long-term submersion, which causes fluorescence signal attenuation. The YEX-S2-BGA-8S achieves selective detection of cyanobacteria through fluorescence spectroscopy technology and includes a built-in cleaning brush mechanism, significantly extending manual maintenance intervals.

The sensor uses a 316L stainless steel housing with IP68 protection rating and can be submerged long-term in freshwater or seawater. With a response time of less than 30 seconds, it supports real-time early warning and is suitable for water source early warning stations, aquaculture workshops, landscape water treatment, and other scenarios.

Technical Advantages

Fluorescence Selective Detection

Traditional turbidity or light scattering methods cannot distinguish algae species. The YEX-S2-BGA-8S emits monochromatic light at the characteristic absorption peak of cyanobacteria and only receives the characteristic emission peak fluorescence signal released after excitation. This principle enables selective measurement of blue-green algae concentration in Kcells/mL, with output results showing excellent linearity with laboratory microscope counts (R² ≥ 0.999).

Controllable Turbidity Influence

Fluorescence methods are relatively sensitive to turbidity. The YEX-S2-BGA-8S is optimized for turbidity below 50 NTU. Within this range, measurement accuracy is not significantly affected. For high-turbidity water, pre-filtration or other pretreatment is recommended.

Built-in Self-Cleaning Brush

The measurement window is prone to biofilm (algae, bacteria) or inorganic fouling during long-term submersion. The integrated cleaning brush mechanism allows window cleaning via commands or timing, greatly reducing manual wiping frequency, especially advantageous in eutrophic water bodies such as reservoirs and lakes.

316L Stainless Steel, IP68 Fully Waterproof

The sensor body is made of 316L stainless steel, offering excellent corrosion resistance and mechanical impact resistance. With IP68 protection rating, it can operate stably when submerged within 2 meters depth. The cable is standard 5 meters (customizable), and all connectors use M16-5 pin waterproof plugs.

Low Power Consumption and Fast Response

• Power consumption only 0.2W@12V, compatible with solar power systems

• Response time T90 less than 30 seconds, meeting real-time early warning needs

• Automatic temperature compensation (Pt1000) to reduce the impact of temperature on fluorescence efficiency

YEX-S2-BGA-8S Online Blue-Green Algae Sensor Technical Specifications

YEX-S2-BGA-8S Online Blue-Green Algae Sensor Typical Application Scenarios

• Drinking Water Source Monitoring: Real-time monitoring of blue-green algae concentration at reservoir and lake water intakes to provide early warning of blooms and ensure water supply safety.

• Aquaculture Water Management: Monitor cyanobacteria (Microcystis, etc.) concentration in seawater or freshwater ponds to prevent algal toxins from affecting cultured organisms.

• Landscape Water Bodies and Urban Rivers: Long-term continuous monitoring of park lakes and landscape rivers to support aeration and ecological regulation decisions.

• Marine and Harbor Red Tide Monitoring: Monitor microalgae (cyanobacteria, green algae, red algae) concentration in the ocean for red tide early warning and marine ecological monitoring.

• Algae Cultivation Process Control: Real-time determination of algae concentration in cultivation equipment for process optimization and harvest timing judgment.

Wiring and Installation Instructions

Wiring Definition (5-core shielded cable)

• Red: 12～24VDC Power Positive

• Black: GND Ground

• Blue: 485A

• Green: 485B

• Yellow: 4-20mA Output (optional, leave floating if not used)

Installation Position Requirements

• Maintain ≥5cm from side walls and ≥20cm from bottom

• Avoid installation in dead water zones or areas with dense bubbles

• Blue-green algae distribution is uneven; representative locations or multi-point monitoring is recommended

Waterproof Requirements
All wiring must be waterproofed. The cable should have corrosion resistance, especially when used in seawater or sewage environments.

FAQ

Q1: Can the YEX-S2-BGA-8S distinguish cyanobacteria from other algae?

Yes. It performs fluorescence detection based on the characteristic absorption/emission spectrum of cyanobacteria, offering selectivity superior to ordinary turbidity methods.

Q2: How much does turbidity affect the measurement?

When turbidity is below 50 NTU, measurement accuracy is not significantly affected. Above this value, suspended particles may scatter excitation light or interfere with fluorescence reception. Pretreatment is recommended for high-turbidity water.

Q3: How does the cleaning brush work?

The sensor has a built-in cleaning brush mechanism that can be triggered via Modbus commands or set for timed cleaning to automatically remove biological attachment on the window and reduce manual maintenance.

Q4: What outputs does the sensor support?

Standard RS-485 Modbus/RTU, with optional 4-20mA analog output. Both can coexist (yellow wire is the current output).

Q5: Can it be used in seawater?

Yes. The 316L stainless steel housing has good seawater corrosion resistance and is suitable for marine harbors and seawater aquaculture.

Q6: How to perform calibration?

Use two-point calibration: zero-point calibration with distilled water; slope calibration with standard algae solution. Ensure the sensor is stable for 3–5 minutes before calibration and consider the effect of temperature on fluorescence efficiency.

Q7: Why is the response time faster than YEX-S1-COD-Online-COD-Sensor.html">COD sensors?

The fluorescence method is an optical instantaneous response that does not require chemical reactions or ion equilibrium processes, so T90 is less than 30 seconds, making it suitable for real-time early warning.

Q8: What is the installation depth limit?

Working pressure is less than 0.2MPa, corresponding to water depths within approximately 20 meters. Conventional water quality monitoring is usually used within 2–10 meters.

Summary and Engineering Recommendation

The YEX-S2-BGA-8S is a dedicated sensor designed for long-term online blue-green algae monitoring. Its fluorescence principle enables selective detection of cyanobacteria, the built-in cleaning brush reduces biological contamination interference, and the 316L stainless steel with IP68 protection ensures long-term stability in freshwater or seawater.

In practical engineering, pay special attention to two points: ensure water turbidity does not exceed 50 NTU for reliable data; and since blue-green algae distribution is uneven, arrange sensors at key sections or intakes and verify with multi-point sampling.

For customized ranges, cleaning brush strategies, or to obtain Modbus communication protocol documents, please contact the Yexsensor technical support team. We welcome further discussion on joint development of early warning models or on-site testing solutions.