NSDD-Lite3 Multi-spectral Commercial Water Quality Sensor
The NSDD6 is a self-cleaning spectral water quality sensor capable of real-time monitoring of multiple physical and chemical parameters. Operating without any chemical reagents, it ensures zero secondary pollution to the water. With this sensor, users can instantly access a comprehensive range of water quality data, enabling prompt and accurate assessments of water conditions.
NSDD-Lite3
Commercial-Grade Multi-spectral Water Sensor
The NSDD-Lite3 is an advanced online spectral sensor designed for real-time monitoring of organic water quality indicators. Operating without chemical reagents, the sensor ensures zero secondary pollution to the water source.
It is an ideal solution for a wide range of applications, including commercial water purifiers, central purification systems, ultrapure water machines, secondary water supply equipment, industrial pure water testing, desalination, and laboratory environments. With the NSDD-Lite3, users can access real-time multi-parameter data to assess water quality conditions promptly and accurately.
Key Features:
- Simultaneous Multi-Parameter Monitoring Supports real-time online detection of up to 4 water quality indicators simultaneously.
- Non-contact Spectral Sensing Utilizes advanced optical technology for precise, non-invasive measurements.
- Reagent-free & Zero Consumables Eliminates the need for chemical reagents, preventing secondary pollution and reducing maintenance costs.
- Automatic Temperature Compensation Built-in temperature calibration ensures data accuracy across varying environments.
- Ultra-low Power Consumption Optimized energy efficiency for long-term continuous operation.
- Flexible Communication Options Supports both UART and RS485 interfaces to suit different integration needs.
- High Pressure Resistance Robust design capable of sustained operation in high-pressure environments up to 1.5 MPa.

100% In-House R&D
Space-Flight Proven
Applications
Flexible Installation · Stable & Reliable · Versatile Applications
The NSDD-Lite3 features a compact, integrated design that allows for flexible installation in various piping systems and tanks, meeting the demands of online water quality monitoring across diverse operating conditions. Equipped with a standard G1/2 thread interface, the sensor can be directly mounted using dedicated stainless steel tees or fittings, ensuring a simplified setup and high system compatibility.
In terms of structural and sealing integrity, the NSDD-Lite3 is optimized for long-term online performance. It operates reliably under high-pressure conditions, supporting a continuous working pressure of up to 1.5 MPa—making it ideal for continuous, unmanned industrial and commercial systems.
316L Stainless Steel Body · Hygienic Design · Corrosion Resistance
Constructed with a premium 316L stainless steel housing, the NSDD-Lite3 offers exceptional resistance to corrosion, pressure, and ensures hygienic safety. It is engineered to perform in demanding environments, including pure water, ultrapure water, high-salinity water, and various industrial media. This robust design prevents material leaching and secondary pollution, satisfying the most stringent requirements for high-purity water applications.

| ● Commercial Water Purification Equipment |
| ● Food & Beverage Processing |
| ● Ultrapure Water Systems |
| ● Secondary Water Supply / Pumping Stations / Pipelines |
| ● Industrial Pure Water Testing |
| ● Seawater Desalination |
| ● Laboratory / Medical Equipment |
Installation Methods

Flexible In-line Mounting: Paired with specialized tee accessories, the sensor supports easy pipeline integration. Standard G1/4 threading allows for effortless connection and adaptation to multiple pipe sizes.

Through-Wall Installation: Effortlessly mount the sensor on water tanks or reservoirs to enable continuous online monitoring. Ensure secure sealing to prevent leaks during setup.

Technical Specifications
Absolute Maximum Ratings
| Parameter | Symbol | Value | Unit |
| Supply Voltage | Vcc | -0.3…5.5 | V |
| Max. Operating Current | I_max | 50 | mA |
| Max. Power Consumption | P_max | 250 | mW |
| Digital Port Voltage | Vio | -0.3…5.5 | V |
| Operating Temperature | Topr | 0…50 | ℃ |
| Storage Temperature | Tstg | -10 … 70 | ℃ |
| Operating Water Pressure | Pre | 0…1.5 | MPa |
| Max. Measurement Rate | FD_max | 5 s/reading | / |
* Exceeding the conditions listed above may cause permanent damage to the sensor!
Electrical Connections
The electrical interface for the external control board utilizes a standard XHB 2.54mm 4-pin socket. The pinout details are described below:

The electrical characteristics of the interface are as follows:
| Pin | Symbol | Function | Voltage Requirement |
|---|---|---|---|
| 1 | VCC | Power Supply (Red) | 5V |
| 2 | GND | System Ground (Black) | 0V |
| 3 | RX | UART Data Receiver (Blue) | 0-5V |
| 4 | TX | UART Data Transmitter (White) | 0-5V |
For interface connections, please refer to the diagram below:

Notes:
-
The sensor features a built-in isolated power supply, and the communication interface utilizes optocoupler isolation.
-
A stable power supply is critical for ensuring measurement accuracy and sensor stability. It is recommended to keep the power supply ripple below 20 mV.
-
The maximum voltage level of the digital interface must not exceed 5.5V.
Mechanical Specifications
The product structure is as follows:

Dimensions:

Detailed Specifications
| Parameter | Symbol | MIN | TYP | MAX | Unit | Notes |
| Operating Voltage | Vcc | 4.5 | 5 | 5.5 | V | |
| Operating Current | Iop | 45 | 50 | mA | During measurement | |
| Standby Current | Is | 20 | 23 | 30 | mA | Standby mode |
| Digital Interface Voltage | Vio | 3 | 5 | V | ||
| Communication Distance | D | / | 100 | 100 | cm | |
| Communication Baud Rate | BD | / | 115200 | / | bps | |
| Response Time | T | / | 1 | 3 | S | |
| Recovery Time | T_r | 3 | 5 | / | S | |
| Measurement Interval | T_in | 3 | 5 | / | S | Continuous mode |
| TOC Index | Measurement Range | 0 | 20 | mg/L | ||
| Resolution | / | 0.1 | / | mg/L | ||
| Consistency | -(0.1+R5%) | +(0.1+R5%) | mg/L | k=2, see Note 1 | ||
| Repeatability | -0.04 | 0.04 | mg/L | |||
| Accuracy | -15%FS | 15%FS | mg/L | see Note 2 | ||
| COD Index | Measurement Range | 0 | 20 | mg/L | ||
| Resolution | / | 0.1 | / | mg/L | ||
| Consistency | -(0.1+R5%) | +(0.1+R5%) | mg/L | k=2 | ||
| Repeatability | -0.04 | 0.04 | mg/L | |||
| Accuracy | -15%FS | 15%FS | mg/L | see Note 2 | ||
| UV254 Index | Measurement Range | 0 | 0.5 | AU/cm | ||
| Resolution | / | 0.0001 | / | AU/cm | ||
| Consistency | -0.001 | 0.001 | k=2 | |||
| Repeatability | -0.001 | 0.001 | ||||
| Accuracy | -15%FS | 15%FS | ||||
| Temperature | Range | 0 | 80 | ℃ | ||
| Resolution | / | 0.01 | / | ℃ | ||
| Consistency | -0.5 | 0.5 | ℃ | |||
| Repeatability | -0.2 | 0.2 | ℃ | |||
| Accuracy | -0.5 | 0.5 | ℃ | |||
| Ambient Operating Temp. | Topr | 0 | 25 | 50 | ℃ | |
| Sample Water Temp. | Ts | 0 | 25 | 80 | ℃ | |
| Storage Temp. Range | Tstg | -10 | 25 | 70 | ℃ | |
| Operating Water Pressure | Pre | 0 | 1.2 | MPa | ||
| Connection Size | G1/2 | Thread Type | ||||
| Enclosure Rating | / | IP66 | / | |||
| Dimensions | / | 38 | / | mm | Housing Diameter | |
| Weight | / | 185 | / | g |
Notes:
1. R refers to the sensor Readout. For example, if TOC = 2, the consistency is ±0.2; if TOC = 4, the consistency is ±0.3.
2. FS stands for Full Scale. Due to the complexity of water pollutants, this value indicates the maximum error: Range 1 (0-4 mg/L) has a max accuracy error of ±0.6; Range 2 (4-8 mg/L) has a max accuracy error of ±1.2; Range 3 (8-20 mg/L) has a max accuracy error of ±3.
| Housing Material | PTFE (Teflon), PPS, Aluminum Alloy, etc. |
| Measurement Range | Please contact our sales team for details |
| Cable / Connector | Please contact our sales team for details |
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Dedicated G1/2 Tee Fitting |
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USB-C to TTL Serial Adapter |
| Product Brochure | Download |
| User Manual | Download |
| NSDD6 Debugging Software | Download |
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