YEX-BOD-406 Online BOD Sensor: Solving Traditional BOD Monitoring Pain Points and Achieving Stable and Reliable Real-Time Water Quality Control

In sewage treatment, industrial wastewater discharge, and river and lake water environment monitoring projects, traditional BOD laboratory testing has a long cycle, is time-consuming and labor-intensive, and is difficult to meet the needs of online continuous monitoring. The Yexsensor YEX-BOD-406 online BOD sensor adopts the dual-wavelength fluorescence method to directly quantify the content of dissolved organic pollutants through the fluorescence intensity of organic matter. It also integrates turbidity compensation and self-cleaning functions, effectively solving problems such as turbidity interference, biological attachment, and long-term drift. It provides system integrators and engineering contractors with a high-stability, high-precision, and easy-to-integrate water quality monitoring solution.

Core Advantage Highlights

• Reagent-free design completely eliminates chemical consumption and secondary pollution, reducing full life-cycle operation and maintenance costs.

• Dual-wavelength fluorescence method combined with proprietary algorithms automatically compensates for turbidity interference, achieving high-precision simultaneous measurement of BOD and turbidity.

• IP68 protection rating, POM + 316L stainless steel material, and self-cleaning brush ensure long-term stable operation in harsh water environments.

Product Overview

The YEX-BOD-406 online BOD sensor is a digital multi-parameter sensor developed by Yexsensor for industrial water treatment scenarios. It utilizes the principle that organic matter absorbs ultraviolet light and excites fluorescence. Through a dual-channel design of ultraviolet measurement light source and reference light source, it accurately captures signals of dissolved organic pollutants. At the same time, built-in algorithms compensate for light path attenuation and suspended particle interference, significantly improving measurement reliability.

The sensor can simultaneously output three parameters: BOD, turbidity, and temperature, and supports RS-485 Modbus/RTU protocol, compatible with mainstream PLC, SCADA, and IoT platforms. The low-power design (0.2W@12V) and plug-and-play features make it particularly suitable for continuous deployment in municipal sewage treatment plants, industrial park wastewater treatment stations, and online water quality monitoring stations. Compared with the traditional BOD5 incubation method, the YEX-BOD-406 achieves real-time response with fast response speed and small drift, providing timely and reliable data support for process control and compliance discharge.

Key Advantages of YEX-BOD-406 Online BOD Sensor

Yexsensor always designs products oriented toward actual engineering needs, with a focus on strengthening stability, high precision, and anti-interference capabilities:

Dual-wavelength fluorescence measurement principle: The main measurement light source targets organic matter fluorescence excitation, and the reference light source is used for turbidity and light path attenuation compensation. Proprietary algorithms effectively eliminate suspended particle interference, maintaining measurement accuracy even in high-turbidity water bodies.

Automatic turbidity compensation and multi-parameter integration: Simultaneous measurement of BOD (0～150 mg/L), turbidity (0～100 NTU), and temperature. Built-in compensation mechanism reduces the impact of external environment on BOD readings and improves data consistency.

Hardware reliability design: The housing combines POM engineering plastic and 316L stainless steel, offering strong corrosion resistance; IP68 protection rating supports long-term submerged installation; equipped with a self-cleaning brush, effectively preventing biofilm attachment and reducing the frequency of manual intervention.

Low maintenance and long life characteristics: Reagent-free and pollution-free design avoids chemical replenishment; the self-cleaning brush has a maintenance cycle of up to 18 months; dynamic sealing components can be returned to the factory for replacement after 18 months, ensuring long-term stable operation of the sensor and significantly reducing operation and maintenance burden after system integration.

Digital easy-to-integrate interface: RS-485 Modbus/RTU protocol output, low-power electronic circuit and anti-interference design, convenient for seamless connection with various industrial controllers, data collectors, and cloud platforms, supporting remote monitoring and data transmission.

Strong environmental adaptability: Operating temperature 0～45℃, pressure resistance <0.1 MPa, storage temperature -5～65℃, suitable for water treatment engineering sites in most regions of China.

These advantages enable the YEX-BOD-406 to provide small-drift, fast-response, and high-accuracy measurement results under complex water quality conditions, making it particularly suitable for engineering projects requiring long-term unattended monitoring.

YEX-BOD-406 Online BOD Sensor Technical Specifications

Note: During calibration, it is recommended to perform temperature calibration first, then turbidity calibration, and finally BOD calibration.

YEX-BOD-406 Online BOD Sensor Application Scenarios

YEX-BOD-406 online BOD sensor is widely applicable to the following water treatment and environmental monitoring projects:

1. Municipal sewage treatment plants: real-time BOD monitoring at inlet, aeration tank and outlet, assisting process optimization and compliance discharge control, supporting SCADA system integration.

2. Industrial wastewater treatment systems: online monitoring in wastewater treatment stations of chemical, pharmaceutical, food processing and other industries, helping enterprises grasp organic load changes in real time, optimize treatment efficiency and reduce the risk of exceeding standards.

3. River and lake surface water environment monitoring: deployment of automatic stations at water sources, river sections and lakes to achieve continuous BOD and turbidity data collection, providing reliable basis for environmental supervision.

4. Industrial park comprehensive wastewater treatment facilities: multi-parameter simultaneous monitoring in multi-source wastewater mixing treatment scenarios, assisting the construction of unified water quality management platforms in the park.

5. Smart water management and IoT projects: combined with edge computing gateways and cloud platforms to build remote online monitoring networks, supporting data analysis and early warning functions.

The sensor performs particularly well in water bodies with high suspended solids or strong biological activity, effectively reducing data anomalies caused by biological attachment or turbidity fluctuations.

YEX-BOD-406 Online BOD Sensor Wiring and Installation Guide

Installation Precautions

• Avoid sensor collision with walls or facilities due to water flow impact. In strong flow environments, fixed installation is required.

• Immersion depth does not exceed 2 meters below the water surface. Considering water level fluctuations, the sensor should be placed more than 30 cm below the lowest water level.

• Install in a bubble-free area, with the measuring window facing the water flow direction, and the sensor kept horizontal and firm.

• It is recommended to add a protective sleeve outside the sensor cable to enhance durability in long-term submerged or exposed environments.

Electrical Wiring

The sensor uses a 4-core twisted shielded cable with the following wiring definitions:

• Red wire: Power positive (12～24 VDC)

• Black wire: Power ground (GND)

• Blue wire: 485A

• White wire: 485B

Before wiring, be sure to check the wire sequence and complete waterproof treatment before powering on. For cables that are long-term immersed in water bodies (including seawater) or exposed to air, materials with certain corrosion resistance should be selected.

FAQ

Q1. What are the advantages of YEX-BOD-406 compared to the traditional BOD5 incubation method?

YEX-BOD-406 adopts optical fluorescence method to achieve real-time online measurement, without the need for a 5-day incubation cycle. It has fast response speed, no reagent consumption, avoids secondary pollution, and ensures data reliability through turbidity compensation algorithms.

Q2. How does the sensor handle interference in high-turbidity water bodies?

The sensor has a built-in reference light source and proprietary algorithms that can automatically compensate for turbidity and light path attenuation effects, maintaining stable BOD measurement results even under higher suspended solids concentrations.

Q3. What is the maintenance cycle of the self-cleaning brush?

It is recommended to check and maintain the self-cleaning brush every 18 months. The actual frequency can be adjusted according to the biological activity of the on-site water quality. After 18 months of continuous use, the dynamic sealing components are recommended to be returned to the factory for replacement.

Q4. What host systems does YEX-BOD-406 support for integration?

It supports RS-485 Modbus/RTU protocol and can be directly connected to PLC, DCS, SCADA systems and various industrial IoT gateways to achieve remote data collection and monitoring.

Q5. Is the calibration operation complicated?

It adopts a two-point calibration method, which is simple to operate. Perform zero point calibration (low concentration solution) first, then slope calibration (standard solution). It is recommended to follow the order of temperature → turbidity → BOD. The value is stable after calibration.

Q6. Can the sensor work normally in low or high temperature environments?

Operating temperature range is 0～45℃, storage temperature -5～65℃, which can meet the on-site environmental requirements of water treatment projects in most regions of China.

Q7. If the measured value shows abnormal fluctuations, what could be the possible reasons?

Common reasons include foreign matter attached to the measuring window, damaged self-cleaning brush, or cable connection problems. It is recommended to clean the window surface first and check the brush status. If the problem persists, please contact technical support.

Q8. What after-sales services does Yexsensor provide?

Local after-sales service is provided within one year from the date of sale (excluding damage caused by improper human use). The sensor has undergone 72-hour aging and stability testing before leaving the factory to ensure reliable quality.

Summary and Cooperation Invitation

The YEX-BOD-406 online BOD sensor takes the dual-wavelength fluorescence method as the core, combined with automatic compensation, self-cleaning and digital interface design, providing a stable, high-precision, low-maintenance online monitoring solution for water treatment projects. It not only significantly reduces the operation and maintenance costs of traditional methods, but also improves the overall system reliability and data real-time performance. It is an ideal choice for system integrators and engineering contractors to build professional water quality monitoring platforms.

If you are planning a sewage treatment online monitoring project, smart water management platform construction, or industrial wastewater treatment system upgrade, please feel free to contact the Yexsensor technical team. We will provide model selection suggestions, integration solutions and on-site technical support according to your specific water quality conditions and system requirements, and jointly create an efficient and reliable water environment monitoring solution. We look forward to working with you to promote the in-depth application of water quality monitoring technology in engineering practice.