The DSO-201B smart dissolved oxygen digital sensor always examines how much oxygen is in the water. It can keep a watch on farming, the environment, and water treatment because its detectors are incredibly sensitive. Its standard, industrial-grade design makes sure that it works well and gives you precise, real-time data for managing dissolved oxygen and changing the water process. Finding out how much dissolved oxygen is in the water is a simple and inexpensive approach to check its quality.
★★★★★
Parameters
| Item | Specification |
|---|---|
| Measuring Range | 0~20.00mg/L |
| Resolution | 0.01mg/L |
| Calibration Method | Two-point Calibration |
| Operating Temperature | 0-50℃ |
| Working Pressure | <0.2MPa |
| Power Supply | 24VDC (Compatible with 9-24VDC wide voltage) |
| Signal Output | RS485(Modbus/RTU) + 4-20mA |
| Installation Interface | 3/4″ G Thread |
| Cable Length | 5m standard, other lengths customizable |
| Communication Protocol | Modbus RTU |
| Default Communication Parameters | 9600 N 8 1 |
| Device Address Range | 1-255 (Modifiable via broadcast address 255) |
| Supported Function Codes | 0x03 (Read data), 0x06 (Modify parameters) |
| Wiring Standard | Red:V+, Black:V-, White:A, Blue:B |
Why choose DSO-201B digital sensor?
- High precision detection: 0.01mg/L high-resolution, two-point calibration mode, accurately capturing subtle changes in dissolved oxygen in water and restoring the true oxygen state
- Industrial grade adaptation: able to withstand working temperatures ranging from 0-50 ℃ and working pressures below 0.2MPa, suitable for complex working conditions in multiple scenarios such as municipal, industrial, and aquaculture
- Convenient installation: 3/4 “G universal threaded interface, directly connected to various water treatment pipelines/equipment, no additional adapter accessories required, efficient installation
- Dual signal output: RS485 (Modbus/RTU)+4-20mA dual signal, compatible with PLC/DCS automation systems and conventional digital display instruments, with strong adaptability
Featured Applications
- Aquaculture: Keeping an eye on the amount of dissolved oxygen in fish ponds, shrimp ponds, and aquaculture seedlings in real time to keep the ecosystem in aquaculture in balance.
- Industrial water treatment: checking for dissolved oxygen in circulating water and process water to stop corrosion, oxygen deficit, and the growth of microbes in water bodies
- Monitoring the environment: Online tracking of dissolved oxygen levels in natural bodies of water like rivers, lakes, and landscape water to show how healthy the water is for the environment
- Food and drink: management of dissolved oxygen in drinking water and water used to make drinks to meet production water quality criteria

Installation and wiring
Installation requirements
- 3/4 “G thread interface directly connects to pipelines/equipment, firmly installed to prevent loosening and leakage
- The probe is completely submerged in the water being measured, and it is recommended to install it in areas with gentle water flow, avoiding areas with dense bubbles and strong electromagnetic interference sources
- The probe should be at least 2cm away from the bottom of the container/pipeline to avoid impurities from adhering and affecting the detection. The wiring and power lines should be separated to reduce signal interference
- It is recommended to install aquaculture scenes in the middle and lower layers of water bodies to monitor the true dissolved oxygen status and avoid surface water interference
Electrical wiring (four wire system, color coded)
| Wire Color | Definition | Description |
|---|---|---|
| Red | V+ | 24VDC Power Positive |
| Black | V- | 24VDC Power Negative/GND |
| White | A | RS485A Signal Terminal |
| Blue | B | RS485B Signal Terminal |
| Extension Wire | 4-20mA | 4-20mA Analog Output |
After the wiring is completed, it is necessary to carefully check to confirm that there is no reverse or virtual connection, in order to avoid damaging the sensor after power on; Keep the wiring connections dry to prevent moisture.
Maintenance and Care
Calibration Specification
- Adopting a two-point calibration mode, factory pre calibration is completed, and frequent calibration is not required for non measurement errors that exceed the range
- When calibrating, first rinse the probe with distilled water and absorb the surface moisture, then immerse it in low and high concentration standard dissolved oxygen buffer solutions in sequence
- After the values in each level of calibration solution stabilize (about 3-5 minutes), send the corresponding calibration command through Modbus/RTU
- After calibration, rinse the probe with distilled water, wipe it dry, and put it into use to ensure calibration accuracy
Routine Maintenance
- To keep the sensing parts safe, wipe the probe attachment often with a gentle, damp cloth. Don’t use rough materials that could damage the fragile sensor film.
- If the probe gets scales, you should clean it gently with weak neutral soap and then rinse it with distilled water. Don’t use strong acids or alkalis to clean.
- Take the probe out after a while and rinse it off with clean water. After being soaked in a protected solution, the membrane should be kept in a container that can’t be opened.
- Check the seals on cables and connectors periodically to keep water and rust from making signs that don’t make sense. You need to fix broken wires right away with the right wiring.
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The DSO-201B smart dissolved oxygen sensor is easy to install and maintain, and it gives accurate readings. It keeps an eye on changes in dissolved oxygen levels at 0.01 mg/L and sends out two signals for automation. Industrial-grade design makes it easier to keep an eye on aquaculture, municipalities, and industries. It gives you dissolved oxygen data for water treatment process control and aquaculture ecological protection that is both fast and cheap. The DSO-201B uses modern sensor technology to easily keep an eye on the dissolved oxygen levels in water.
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