YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Product Overview

YEXsensor YEX-RDO-206 online fluorescence dissolved oxygen sensor (model: YEX-RDO-206) is an industrial-grade digital sensor developed by Yexsensor for online continuous monitoring of dissolved oxygen (DO) in water. The sensor adopts advanced fluorescence quenching principle: when excitation light irradiates the fluorescent membrane cap, the fluorescent material is excited to produce fluorescence, and oxygen molecules quench the fluorescence. By detecting the phase difference between fluorescence and excitation light and comparing it with the internal calibration curve, the oxygen concentration is accurately calculated, and then automatically compensated by temperature and salinity before outputting the final measurement value.

Compared with traditional electrochemical dissolved oxygen sensors, the YEX-RDO-206 has significant advantages: no need to add electrolyte, no polarization; no oxygen consumption, unaffected by water flow velocity; not interfered by chemical substances such as sulfides; extremely small drift, more accurate and stable measurement. The fluorescent membrane cap is easy to replace, has a long service life, and significantly reduces usage costs.

The sensor integrates a Pt1000 temperature sensor to achieve automatic temperature compensation and supports flexible salinity compensation parameter settings. It outputs standard RS-485 Modbus RTU protocol, which can be directly connected to PLC, DCS, industrial control computers, paperless recorders or touch screens and other third-party equipment without additional transmitters, simplifying system integration and reducing project costs.

The housing combines POM, ABS/PC alloy and 316L stainless steel materials, which is lightweight and has excellent corrosion resistance. The standard 3/4NPT pipe thread supports submersible installation and is suitable for pipelines, tanks and open water bodies. The standard cable length is 5 meters (customizable), and the connector is M16-5 core waterproof male connector. The IP68 protection rating ensures the sensor can be immersed in water for long-term use. The low power consumption design (0.2W@12V) combined with 12～24V DC wide voltage power supply is particularly suitable for remote or solar-powered on-site applications.

Yexsensor strictly controls product quality. Every YEX-RDO-206 sensor undergoes 72-hour aging tests and stability verification to ensure zero defects upon delivery, providing reliable guarantee for users' water quality dissolved oxygen monitoring.

YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Core Technical Advantages

Unique Advantages of Fluorescence Measurement Principle

• No electrolyte required, no polarization

• No oxygen consumption, unaffected by flow velocity

• Not interfered by chemical substances such as sulfides

• Small drift, fast response, accurate measurement

Intelligent Compensation and High Stability

Built-in Pt1000 temperature sensor realizes automatic temperature compensation and supports flexible salinity compensation parameter settings to ensure accurate and reliable data under different water quality conditions. Range 0～20.00 mg/L (0～200% saturation at 25℃), resolution 0.01 mg/L, accuracy ±2%, response time T90＜30s, minimum detection limit as low as 0.08 mg/L.

Digital Integration and Low-Maintenance Design

RS-485 Modbus RTU protocol output supports long-distance transmission and multi-device networking. The fluorescent membrane cap has a service life of about 1 year (under normal use), is easy to replace, simple to maintain, and significantly reduces long-term usage costs.

Rugged and Easy to Install

The IP68 protection rating combined with high-quality housing material adapts to working environments of 0～50℃ and ≤0.2MPa. The submersible installation method is flexible and particularly suitable for various water treatment site deployments.

These core advantages make the YEXsensor YEX-RDO-206 an ideal upgrade replacement for traditional electrochemical dissolved oxygen sensors, helping users achieve more stable and lower-cost online dissolved oxygen monitoring.

YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Technical Specifications

YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Wide Application Scenarios

The YEXsensor YEX-RDO-206 online fluorescence dissolved oxygen sensor, with its maintenance-free characteristics, high stability and digital integration capabilities, is widely used in the following fields:

• Municipal and Drinking Water Treatment
  In water treatment plants, secondary water supply systems, and pipe network monitoring, real-time dissolved oxygen levels are mastered to optimize aeration processes and ensure water quality safety.

• Sewage Treatment and Environmental Monitoring
  Monitoring in aeration tanks, aerobic tanks, and outlets of sewage treatment plants, as well as environmental water bodies such as rivers and lakes, helps precisely control aeration volume, reduce energy consumption, and ensure discharge compliance.

• Industrial Water Treatment Systems
  In circulating cooling water, process water and wastewater treatment in power plants, chemical, pharmaceutical, food and beverage, papermaking and other industries, precise monitoring of dissolved oxygen prevents anaerobic corrosion or excessive microbial growth.

• Aquaculture and Ecological Farming
  In fish, shrimp, crab and other aquaculture ponds, real-time monitoring of dissolved oxygen concentration avoids breeding losses caused by hypoxia and improves survival rate and yield.

• Other Professional Fields
  Including laboratory water quality analysis verification, seawater desalination process monitoring, bioreactor control, etc. Whether for continuous online monitoring or process optimization, the YEX-RDO-206 can provide stable and reliable data support.

Yexsensor helps users build intelligent dissolved oxygen monitoring systems through this sensor, achieving energy saving, process optimization and environmental compliance.

YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Installation and Electrical Connection

Installation Requirements

The sensor should be fixed and immersed below the liquid surface, using 3/4NPT pipe thread to screw directly into pipelines, tanks or brackets. Avoid collision or scratching the fluorescent membrane cap surface during installation and use to prevent sediment from attaching to the fluorescent membrane cap. Before use, please remove the rubber protective cap to ensure the fluorescent membrane cap is in a good flowing state.

Electrical Connection

The cable adopts 4-core twisted shielded wire, with the following wiring definitions:

• Red wire: Power positive pole (12～24V DC)

• Black wire: Ground (GND)

• Blue wire: 485A

• White wire: 485B

Before powering on, carefully check the wiring sequence to avoid reverse connection damaging the equipment. All wiring must be waterproof and anti-corrosion treated. The cable should have certain corrosion resistance. The sensor connector is M16-5 core waterproof male connector to ensure a sealed and reliable connection.

After installation, it is recommended to power on and run in clean water for a period of time, confirm that the data is stable before calibration.

YEXsensor YEX-RDO-206 Online Fluorescence Dissolved Oxygen Sensor Maintenance and Calibration Guide

Maintenance Schedule Recommendations

Maintenance Methods

• Sensor outer surface: Rinse with clean water. For stubborn dirt, add a small amount of household detergent and wipe with a damp soft cloth.

• Fluorescent membrane cap surface: Rinse with clean water or gently wipe with a soft cloth. Avoid scratching the measurement area.

• Inside the fluorescent membrane cap: If water vapor or dust enters, unscrew the cap, rinse the inner surface and optical window with clean water, dry and reinstall.

• Cable inspection: Ensure the cable is not damaged, wiring points are not immersed in water, and the cable is not overly tight during installation.

• Fluorescent membrane cap storage: When not in use, cover with a rubber protective cap containing a wet sponge to keep the measurement area moist. If it dries for a long time, soak in water for 48 hours before use.

Calibration Operation (Two-point Calibration)

1. Zero point calibration: Prepare 5% sodium sulfite solution (5g sodium sulfite dissolved in 95mL water), place the sensor in the solution, and execute the zero point calibration command after the value stabilizes for 3 minutes.

2. Slope calibration: Place the sensor in air-saturated water (or water-saturated air), and execute the slope calibration command after the value stabilizes for 3 minutes.

Air-saturated water preparation method: Add 2/3 volume of fresh distilled water in a constant temperature water bath, float a porous plastic plate on the water surface, continuously aerate for more than 1 hour, and let it stand for 20 minutes before use.

Precautions

• Avoid exposing the inner surface of the fluorescent membrane cap to direct sunlight

• Do not touch the fluorescent membrane directly with hands

• Avoid air bubbles attaching to the fluorescent membrane surface during measurement and calibration

• Avoid applying any mechanical stress (pressure, scratches, etc.) to the fluorescent membrane

Quality Assurance and Service Support

Yexsensor quality inspection department strictly follows specifications to conduct 72-hour aging tests and stability tests on each YEX-RDO-206 to ensure high-quality delivery. We provide one-year after-sales service from the date of sale (excluding damage caused by improper use). For repairs, please send it back to the company with good packaging, and we will repair the relevant damaged parts free of charge.

Standard accessories include:

• 1 × YEX-RDO-206 sensor

• 1 × User manual

• 1 × Certificate of conformity

• 1 × 5-meter cable

Optional accessories include spare fluorescent membrane caps, extension cables, mounting brackets, etc. Cable length customization and other personalized needs are supported.

Yexsensor professional technical team can provide full guidance on model selection consultation, installation and commissioning, and system integration.

Common Questions and Answers (FAQ)

Q1: What are the main advantages of YEX-RDO-206 compared with traditional electrochemical dissolved oxygen sensors?

A1: No electrolyte required, no oxygen consumption, not affected by flow velocity and sulfide interference, small drift, simple maintenance, longer service life, and lower cost.

Q2: How often does the fluorescent membrane cap need to be replaced?

A2: It is recommended to replace it once a year under normal use. The specific timing can be adjusted according to actual working conditions.

Q3: How to perform two-point calibration?

A3: Zero point calibration uses 5% sodium sulfite solution, and slope calibration uses air-saturated water or water-saturated air. The operation is simple. Detailed instructions can be found in the appendix or by contacting technical support.

Q4: Does the sensor support salinity compensation?

A4: Yes. It has built-in salinity compensation function. Users can flexibly set parameters according to actual water quality to ensure measurement accuracy.

Q5: What should be noted during installation?

A5: Avoid collision or scratching the fluorescent membrane cap. After installation, remove the rubber protective cap to ensure the membrane cap is immersed below the liquid surface with good flow.

Q6: What to do if the measurement value is unstable?

A6: Check whether the fluorescent membrane cap is tightened, whether there are attachments on the surface, whether it is damaged or has exceeded its service life, and clean or replace it.

Q7: What application scenarios is this sensor suitable for?

A7: It is widely suitable for municipal drinking water, sewage treatment, industrial water treatment, aquaculture and other fields, especially for online monitoring projects that require low maintenance and high stability.

Q8: Does Yexsensor provide batch customization services?

A8: Yes. We can customize cable length, special installation solutions or integration requirements. Bulk users are welcome to contact us for exclusive quotes and technical support.

The YEXsensor YEX-RDO-206 online fluorescence dissolved oxygen sensor has become the preferred device in the field of water quality monitoring with the advanced nature of fluorescence technology, low-maintenance characteristics and digital integration advantages. Yexsensor is committed to providing you with professional and reliable dissolved oxygen monitoring solutions to help achieve energy saving optimization and precise water quality management.

Welcome to contact Yexsensor for the latest quotation, technical information or on-site demonstration to jointly build an efficient and intelligent water quality monitoring system.