Product Description

Yexsensor brand YEX-iDO-306 adopts leading fluorescence quenching technology, requires no electrolyte replacement, features a maintenance-free design, and supports RS485 digital output. It is suitable for high-standard water quality monitoring scenarios such as smart agriculture, sewage treatment, and industrial process monitoring.

Precise Insight into Water Oxygen Content: YEX-iDO-306 High-Precision Online Fluorescence Dissolved Oxygen Sensor

In modern industrial water treatment and high-density aquaculture, the content of dissolved oxygen (DO) is a core indicator for measuring water quality and health. Yexsensor's YEX-iDO-306 integrated online fluorescence dissolved oxygen sensor completely overturns the maintenance pain points of traditional membrane electrodes. With its excellent stability, long service life, and digital communication capabilities, it is becoming the preferred water quality monitoring component for global system integrators and engineering companies.

Core Technology: Cutting-edge Monitoring Based on Physical Quenching Principle

The core of the YEX-iDO-306 sensor lies in its advanced fluorescence quenching principle.

Unlike traditional electrochemical sensors, the high-performance blue LED integrated inside YEX-iDO-306 illuminates the sensitive material on the surface of the fluorescent cap. After being excited, the fluorescent material emits red light. Since oxygen molecules can absorb energy (quenching effect), the release time and phase of the red light will change with the increase of oxygen density.

By accurately detecting the phase difference between red light and blue light through the built-in microprocessor and combining it with real-time temperature compensation algorithm, the sensor can directly output the corrected dissolved oxygen concentration or saturation value. This non-chemical reaction measurement method ensures that the sensor can still maintain extremely high accuracy and extremely low zero-point drift during long-term operation.

Eight Core Advantages of YEX-iDO-306 Online Fluorescence Dissolved Oxygen Sensor

• Maintenance-free design: No need to replace electrolyte, no polarization required, greatly reducing labor costs for later operation and maintenance.

• Zero dependence on flow velocity: No oxygen is consumed during measurement, and accurate data can still be provided even in static water or environments with slow flow velocity.

• Intelligent dual compensation: Built-in Pt1000 temperature sensor supports full automatic temperature compensation; flexible salinity compensation settings are also provided.

• Strong anti-interference: Not affected by chemical substances such as H₂S (hydrogen sulfide), nor by electromagnetic interference, with stable data output.

• Fast response performance: Optimized fluorescent film design, T90 response time less than 30 seconds, real-time reflection of water quality changes.

• High-standard protection level: IP68 protection design, the shell is composed of POM, ABS and 316L stainless steel, with excellent corrosion resistance.

• Digital communication: Standard RS-485 interface, supports Modbus-RTU protocol, can be easily connected to PLC, DTU or various smart cloud platforms.

• Extremely low operating cost: The fluorescent membrane head has a service life of up to 1 year and is extremely easy to replace, with overall power consumption of only 0.2W.

Technical Performance and Specifications of YEX-iDO-306 Online Fluorescence Dissolved Oxygen Sensor

Wide Application Scenarios of YEX-iDO-306 Online Fluorescence Dissolved Oxygen Sensor: From Laboratory to Extreme Environments

The design intention of YEX-iDO-306 is to provide a “one-stop” monitoring solution for various complex water environments.

1. Smart Aquaculture
   In high-density aquaculture, hypoxia is the primary cause of fish and shrimp death. YEX-iDO-306 can link with aerators in real time, precisely control energy consumption through monitoring, and achieve energy saving and efficiency improvement while ensuring biological safety.

2. Municipal Sewage Treatment
   In activated sludge process and aeration tank control, dissolved oxygen concentration directly affects microbial activity. The sensor can withstand complex chemical components in sewage, provide accurate data support for aeration systems, and optimize process flow.

3. Environmental Surface Water Monitoring
   Suitable for automatic water quality monitoring stations in rivers, lakes, wetlands and coastal areas. The long-distance transmission characteristics of RS485 combined with solar power supply system can realize remote unattended monitoring.

4. Industrial Circulating Water and Process Monitoring
   In circulating cooling water systems of power, chemical and other industries, controlling dissolved oxygen is the key to preventing pipeline corrosion. The sturdy shell of YEX-iDO-306 can cope with certain industrial pressure environments.

Installation and Electrical Connection Guide for YEX-iDO-306 Online Fluorescence Dissolved Oxygen Sensor

To ensure measurement accuracy, please follow the following installation specifications:

Physical Installation

• Immersion installation: The sensor should be submerged below the liquid surface. It is recommended to use 3/4 NPT thread to fix it on the bracket.

• Protection measures: It is strictly forbidden to collide with or scratch the fluorescent membrane surface. The installation position should avoid areas with more sediment to prevent the membrane head from being covered by sludge.

• Operation preparation: The black rubber protective cover must be removed before putting into use.

Electrical Wiring (4-core twisted-pair shielded wire)

• Red (VCC): 12～24V DC

• Black (GND): Ground wire

• Blue (485A): RS-485 signal +

• White (485B): RS-485 signal -

FAQ: Common Questions and Technical Support

Q1: What is the biggest advantage of YEX-iDO-306 compared with traditional membrane (polarographic) sensors?

A1: The biggest advantage is “zero maintenance” and “zero flow velocity requirement”. Membrane sensors require regular replacement of electrolyte and oxygen-permeable membrane, and water flow must be maintained to measure. YEX-iDO-306 requires no consumables and can obtain accurate values in still water, with extremely low long-term operating costs.

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

A2: Under normal use conditions, we recommend replacing the fluorescent membrane head once a year. If the measurement environment contains strongly abrasive particles or strong acid and alkali, it is recommended to check the integrity of the membrane surface every six months.

Q3: Why has the sensor’s response speed slowed down?

A3: This is usually because biofilm or dirt has attached to the fluorescent membrane surface. It is recommended to gently wipe the membrane head surface with clean water and a soft cloth every 30 days. If the industrial wastewater contains oil, it can be cleaned with diluted household detergent.

Q4: Does the sensor support connection to my existing PLC system?

A4: Yes. The sensor adopts the standard Modbus-RTU protocol and is compatible with most PLCs on the market (such as Siemens, Mitsubishi, etc.) and industrial host computer software.

Q5: What should I pay attention to when storing the sensor?

A5: When not in use, cover it with the protective cover containing a moist sponge to keep the fluorescent membrane moist. If the membrane head is dry for a long time, it will cause data drift. If it has dried out, please soak it in clean water for 48 hours before use.

Q6: What may be the cause of abnormal fluctuations in measurement data?

A6: First check whether the fluorescent membrane head is tightened; secondly observe whether there are air bubbles attached to the membrane surface, as air bubbles will cause high or fluctuating readings; finally check whether the RS-485 shielded wire is correctly grounded to eliminate electromagnetic interference.

Q7: How to perform on-site calibration?

A7: YEX-iDO-306 supports two-point calibration. Zero point calibration uses 5% sodium sulfite oxygen-free water; slope calibration (full point) usually uses air-saturated water (prepared by aeration). Usually, the sensor has been calibrated before leaving the factory and does not require frequent calibration.

Q8: Can this sensor directly measure seawater?

A8: Yes. YEX-iDO-306 has built-in salinity compensation parameters. Users can set the environmental salinity value through Modbus commands to obtain accurate concentration readings corrected for seawater environment.

Quality Commitment and Service

Yexsensor always adheres to the manufacturing standard of “quality first”. Every YEX-iDO-306 has undergone 72-hour high-temperature aging test and full-range stability test before leaving the factory to ensure that every product delivered to customers meets IP68 protection level and measurement accuracy requirements.

Warranty period: Provide one-year limited warranty service from the date of sale (excluding physical damage to the fluorescent cap and improper use).

Standard configuration: Sensor host (including 5m cable), product manual, certificate of conformity.

If you have further technical requirements for smart water integration and large-scale aquaculture monitoring, please feel free to contact our engineering support team.