NBL-BOD-406-S UV Fluorescence Online Water Quality BOD Sensor UV Fluorescence Self-Cleaning Water Quality Probe

Real-time, Accurate, Zero Reagent: NiuBoL NBL-BOD-406-S Online Digital BOD Sensor

In modern industrial sewage treatment and surface water environmental monitoring, the traditional five-day biochemical oxygen demand (BOD₅) analysis method has become difficult to meet the automation control needs of today's smart water affairs due to its long time consumption, cumbersome operation and inability to provide real-time data.

NiuBoL deeply focuses on industry pain points and launches the NBL-BOD-406-S digital online BOD sensor. This product is based on 275nm ultraviolet fluorescence excitation technology and compensated by digital algorithms, completely bidding farewell to the secondary pollution and frequent maintenance of traditional chemical methods.

Real-time monitoring, instant feedback: T90 response time is less than 30 seconds, providing reliable data support for process closed-loop control.

Zero reagent low cost: No need to purchase or replace chemical agents, long-term operating costs are almost zero.

Industrial-grade easy integration: Standard RS485 Modbus protocol, seamlessly connects with various PLC, DCS and IoT gateways.

NBL-BOD-406-S Online Water Quality BOD Sensor Product Overview

NiuBoL NBL-BOD-406-S is a high-performance online water quality analyzer specially designed for monitoring organic pollutant concentration under complex working conditions. It cleverly utilizes the characteristic absorption and fluorescence excitation properties of organic substances to ultraviolet light, converting the content of dissolved organic matter in water into precise electrical signal output.

The sensor not only integrates BOD measurement but also has built-in high-precision temperature compensation to ensure measurement stability under different water temperature environments. For engineering contractors, its micro-power consumption design and robust 316L stainless steel shell make it the preferred component in harsh environments such as field unmanned stations and aeration tanks of sewage treatment plants.

Technical Advantages

1. Physical optical principle, green and pollution-free
Unlike the potassium dichromate method or BOD₅ method, NiuBoL NBL-BOD-406-S does not rely on chemical reactions. It excites fluorescence with 275nm ultraviolet light and directly senses the physical properties of organic matter. This non-destructive measurement method not only ensures the immediacy of monitoring but also avoids secondary damage to the environment from chemical reagents.

2. Excellent material and protection level
The sensor body adopts 316L stainless steel material, with extremely strong corrosion resistance, capable of coping with long-term immersion in urban sewage and some acid-base industrial wastewater. The whole machine reaches IP68 waterproof level and can work stably for a long time within 2 meters water depth, fearless of moisture and flooding risks.

3. Advanced self-cleaning and dynamic sealing technology
Aiming at the industry problem of biological fouling and impurity attachment, NBL-BOD-406-S can be optionally equipped with a high-efficiency self-cleaning electric brush, combined with a long-life dynamic sealing device (factory maintenance cycle up to 18 months). This significantly reduces the frequency of on-site manual maintenance and ensures the transparency of the optical window and data continuity.

4. Digital anti-interference architecture
Adopting full digital signal processing, the RS-485 interface cooperates with the Modbus/RTU standard protocol, giving it extremely strong anti-electromagnetic interference capability. It supports signal long-distance transmission up to hundreds of meters without losing accuracy, greatly facilitating system integrators to carry out large-scale networking.

NBL-BOD-406-S Online Water Quality BOD Sensor Technical Specifications

NBL-BOD-406-S Online Water Quality BOD Sensor Application Scenarios

Municipal Wastewater Treatment Plants: Used for BOD load monitoring at inlet and outlet, real-time adjustment of aeration volume, and optimization of energy consumption.

River and Lake Surface Water Monitoring: As the core unit of water quality early warning system in smart river chief system projects, monitoring sudden organic pollution events.

Industrial Process Water Quality: Real-time monitoring of circulating water and discharge water in papermaking, printing and dyeing, food processing and other industries.

Rural Decentralized Sewage Treatment: With low maintenance features, it is suitable for unmanned automated monitoring stations in remote areas.

NBL-BOD-406-S Online Water Quality BOD Sensor Wiring and Installation Guide

1. Quick Wiring Instructions

NiuBoL sensor adopts standard 5-core waterproof cable with rigorous and clear wiring logic:

• Red wire: Power positive pole (12-24VDC)

• Black wire: Power ground (GND)

• Blue wire: RS485-A

• White wire: RS485-B

Note: Before powering on, please confirm the wire sequence and ensure all connection points have been treated with industrial-grade waterproofing to prevent capillary phenomenon from causing moisture inside the sensor.

2. Installation Suggestions

• Installation Depth: It is recommended to submerge at least 30cm underwater, and the maximum depth should not exceed 2 meters, to avoid floating objects on the water surface and ensure pressure safety.

• Water Flow Direction: The measurement window should face the water flow direction, and the installation position should avoid bubble accumulation areas to reduce interference of bubbles on the optical path.

FAQ

Q1. What is the correlation between the data measured by NBL-BOD-406-S and traditional BOD₅?

Since the fluorescence intensity of organic matter has a high correlation with BOD₅, the sensor has been modeled with a large number of standard sample solutions at the factory. Under specific working conditions, users can further optimize the correlation coefficient through on-site two-point calibration.

Q2. How often does the sensor need to be calibrated?

This depends on the application environment. In relatively clean water bodies, calibration is usually required once every 3-6 months; at the inlet of sewage plants, it is recommended to check once a month.

Q3. Can this sensor measure high-salinity water quality (such as seawater)?

Yes. The sensor shell adopts 316L stainless steel, which has good salt spray resistance. However, for long-term use in seawater, it is necessary to strengthen the cleaning of biological attachment on the window.

Q4. Why is tryptophan (Tryptophan) solution required for calibration?

Tryptophan is an internationally recognized standard calibration substance for fluorescence water quality analysis, and its excited fluorescence characteristics are highly consistent with dissolved organic matter.

Q5. Can the sensor work normally in low-temperature environments?

The working range of NBL-BOD-406-S is 0-45℃. As long as the water body does not freeze, the sensor can measure normally. Its built-in temperature sensor will automatically perform data compensation.

Q6. If the measured value shows continuous fluctuation, what may be the reason?

It is usually caused by bubbles near the measurement window or large suspended particles blocking it. Please check whether the self-cleaning brush is working normally and ensure the installation position has steady water flow.

Q7. Can data be read directly without a PLC?

Yes. Since it outputs standard Modbus signals, you can use an RS485 to USB converter together with the host computer software provided by NiuBoL to read data directly on the computer.

Q8. Is the dynamic sealing device required to be returned to the factory for replacement every 18 months?

18 months is the recommended cycle to ensure safety under high water pressure and continuous mechanical cleaning environments. If the application environment has extremely low pressure and low cleaning frequency, it can be appropriately extended, but regular factory maintenance can greatly improve the overall life of the sensor.

Summary and Engineering Support

NiuBoL NBL-BOD-406-S online BOD sensor is a professional tool born to cope with complex water quality challenges. Its digital, reagent-free design concept precisely meets the core requirements of "high reliability, zero maintenance, and easy integration" for water quality monitoring equipment in the Industry 4.0 era.

Are you looking for higher cost-effective components for real-time monitoring solutions in sewage treatment projects?

Our technical engineer team can provide you with detailed register description documents and installation integration guidance. Contact us immediately to obtain the latest NiuBoL sensor quotation and complete technical manual.

NBL-BOD-406-S Online BOD Sensor User Manual Data Sheet

NBL-BOD-406-S Online BOD Sensor.pdf