The KSA-DOY-02 optical dissolved oxygen digital sensor is designed based on the core principle of dynamic fluorescence quenching, specifically designed for online continuous monitoring of dissolved oxygen in conventional water treatment scenarios. It eliminates the drawbacks of traditional membrane based electrolyte consumption, integrates triple automatic compensation for temperature, pressure, and salinity, industrial grade IP68 water protection, fast response speed, and low maintenance cost. It is a cost-effective intelligent solution for dissolved oxygen monitoring in municipal water treatment, aquaculture, environmental monitoring, and other fields.
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Parameters
| Item | Specification |
|---|---|
| Measuring Principle | Dynamic Fluorescence Quenching |
| Measuring Range | 0~20mg/L (0~200% saturation) |
| Resolution | 0.01mg/L (DO), 0.1℃ (Temperature) |
| Accuracy | ±2%F.S. (DO), ±0.5℃ (Temperature) |
| Response Time | 40s T90 |
| Compensation Function | Automatic temperature/pressure/salinity compensation |
| Temperature Compensation | PT1000 |
| Operating Temperature | 0~45℃ |
| Working Pressure | ＜0.2MPa |
| Waterproof Grade | IP68 (20m water depth) |
| Power Supply | 12/24VDC±10%, 10mA |
| Signal Output | RS485 (Modbus/RTU Protocol) |
| Installation Interface | 3/4″ NPT Taper Thread |
| Calibration Method | Two-point Calibration (Zero + Slope) |
| Cable Length | 5m standard, customizable |
| Housing Material | SUS316 Stainless Steel / POM (optional) |
| Service Life | Sensor ≥3 years, Fluorescent cap ≥1 year |
| Overall Size | Φ30mm × 189mm |
| Power Consumption | Low power consumption (internal anti-interference design) |
Why choose KSA-DOY-02 dissolved oxygen digital sensor?
- Fluorescence method with no consumables: no electrolyte, no dissolved oxygen consumption in water, no secondary pollution during measurement, eliminating the problem of frequent electrolyte replacement in membrane electrodes.
- Triple automated compensation: PT1000 temperature, pressure, and salinity sensors, full-dimensional environmental interference cancellation, more accurate measurement data.
- Quick response: T90 requires no power polarisation or preheating, responding in 40 seconds and ready for immediate measurement after initiation, ideal for on-site monitoring.
- Exclusive filter design resists external light source interference, internal circuit optimised for anti-interference, data stable under difficult operating situations.
Featured Applications
- Municipal water treatment keeps an eye on the amount of dissolved oxygen in the biochemical tanks of sewage treatment plants and the aeration tanks of water plants to make sure they are working well.
- Aquaculture: To check the quality and oxygenation of the water, dissolved oxygen levels are checked in fish, prawn and nursery ponds.
- You can find out if water in rivers, lakes, and landscapes is polluted and healthy for the environment by measuring the amount of dissolved oxygen in it online.
- In the chemical and light industries, industrial water treatment keeps an eye on the amounts of dissolved oxygen in cooling water and process circulation water to stop microbes from growing and equipment from getting damaged by low water oxygen levels.
Installation and wiring
Installation requirements
- Supports 7 installation methods including sinking, floating, drainage, 1/2 “/3/4″/1 “pipeline, side insertion, and top insertion, with flexible selection based on on-site conditions
- It must be installed in areas with slow water flow and no bubbles to avoid fluctuations in measurement data caused by turbulent water flow and dense bubbles
- The 3/4 “NPT taper thread interface is firmly connected to the pipeline/installation bracket to prevent loosening and leakage, ensuring that the probe is completely submerged in the measured water body
- The cable should be made of flexible twisted pair shielded wire, and the wiring should be separated from the power line. Waterproof sealing should be done at the connection point to avoid electromagnetic interference and water corrosion
Electrical wiring (four wire system, color coded)
| Wire Color | Signal Definition | Instruction |
|---|---|---|
| Brown | V+ | 12/24VDC Power Positive |
| Black | GND | Power Negative / Ground |
| Blue | RS485A | RS485 Signal A |
| White | RS485B | RS485 Signal B |
| Bare Wire | Shield Layer | Cable shielding, anti-interference |
Before wiring, be sure to cut off the power and confirm that the positive and negative poles are not connected in reverse; After the wiring is completed, check the firmness of the circuit. In humid environments, waterproof sealing treatment should be applied to the wiring terminals; The cable is a 4-core AWG-24/AWG-26 shielded wire with an outer diameter of 6.0-6.2mm and is resistant to bending and stretching.
Maintenance and Care
Calibration of zero points (anaerobic water calibration)
- Add 2g of sodium sulphite to 98mL of distilled water. To make 2% sodium sulphite anaerobic water, stir it well.
- Put the sensor probe all the way into anaerobic water and let it sit for three minutes, or until the value stays the same.
- To finish zero calibration, send the zero calibration instruction (register 0x1001, write 0) using Modbus/RTU.
- After calibrating, take the sensor off right away. Rinse the surface with distilled water and use a soft cloth to soak up the water so that leftover sodium sulphite doesn’t corrode the probe.
Routine Maintenance
- Clean the fluorescent film head attachment every 30 days. Do not use hard objects to scrape, only gently wipe with a soft damp cloth, or rinse the surface with slow water flow
- When the fluorescent cap head is worn or the fluorescent material falls off, it should be replaced in a timely manner. When replacing, it is necessary to confirm that the waterproof sealing ring is not missing to ensure the sealing effect
- When the sensor is idle for a long time, clean it thoroughly and store it with a protective cover covered with moist protective cotton; If stored dry for a long time, the probe should be soaked for 48 hours before reuse
- It is recommended to choose a dedicated protective cover to prevent microorganisms from adhering to the surface of the membrane head and affecting measurement accuracy
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The KSA-DOY-02 optical dissolved oxygen sensor features fluorescence quenching method without consumables, triple compensation with high precision, easy installation in multiple scenarios, and long lifespan with low maintenance as its core highlights. It completely eliminates the pain points of traditional dissolved oxygen electrodes and is suitable for monitoring dissolved oxygen in all scenarios of conventional water treatment. Choose KSA-DOY-02, let intelligent optical sensing technology safeguard your water quality dissolved oxygen control, worry free, efficient, and more durable!
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