NBL-DDM-406-S Industrial-grade Online Salinity Sensor: For Seawater, Aquaculture,High-Salt Water Treatment Monitoring

NBL-DDM-406-S Industrial-grade Online water Salinity Sensor

High-salinity water monitoring often faces problems such as fast electrode corrosion, obvious temperature drift, limited installation, and signal interference, resulting in unstable measurement, frequent maintenance, and increased system integration difficulty. The NiuBoL NBL-DDM-406-S online salinity sensor adopts inductive electrode method and high-corrosion-resistant material design, effectively solving these engineering pain points and providing system integrators and engineering contractors with a high-precision, strong-stability, and easy-to-integrate online salinity monitoring solution.

NBL-DDM-406-S Online Salinity Sensor Core Advantages

• Inductive Electrode Measurement: Non-contact inductive principle reduces electrode pollution and corrosion, ensuring long-term measurement stability.

• Automatic Temperature Compensation: Integrated Pt1000 sensor provides real-time compensation for temperature effects, ensuring high-precision output within 0～50℃.

• Digital Integrated Output: RS-485 Modbus RTU protocol supports seamless connection to PLC, DCS, SCADA and other systems, with optional 4-20mA analog output.

NBL-DDM-406-S Online Salinity Sensor Product Overview

The NiuBoL NBL-DDM-406-S online salinity sensor is specially designed for seawater, high-salt water and various industrial water treatment scenarios. Based on the inductive electrode method principle, it accurately measures the salinity (PSU) of water bodies. The product has fast response (T90＜30s), resolution of 0.1 PSU, and minimum detection limit of 0.1 PSU, making it suitable for application environments requiring continuous and reliable salinity data.

The sensor supports RS-485 bus and standard Modbus RTU communication protocol, which can be directly connected to PLC, DCS, industrial control computers, touch screens and other third-party equipment to achieve remote data transmission and system linkage. Optional 4-20mA current output further enhances compatibility with traditional control systems.

The whole machine adopts ABS and TC4 titanium alloy housing, with outstanding seawater corrosion resistance. It has IP68 protection rating and supports long-term submerged installation (working pressure ≤0.6 MPa). The 3/4 NPT standard pipe thread interface makes installation convenient, particularly suitable for long-term online monitoring in complex working conditions such as seawater aquaculture, marine monitoring, and industrial high-salt water treatment, significantly reducing maintenance costs and system deployment difficulty.

NBL-DDM-406-S Online Salinity Sensor Core Technical Advantages

• Inductive Electrode Technology: Adopts non-contact inductive measurement principle, avoiding the problems of easy pollution and corrosion of traditional electrodes, reducing maintenance frequency, and improving long-term stability in high-salinity environments.

• Automatic Temperature Compensation: Built-in high-precision Pt1000 temperature sensor performs real-time automatic compensation to ensure salinity measurement is not affected by temperature fluctuations, with accuracy of ±1% of reading and temperature ±0.3℃.

• High Corrosion-Resistant Material Protection: The housing is composed of ABS and TC4 titanium alloy, with excellent resistance to seawater and strongly corrosive media. Combined with IP68 protection rating, it can withstand water pressure ≤0.6 MPa for a long time and is suitable for harsh water environments.

• Digital Communication and Anti-interference: Standard RS-485 Modbus RTU protocol uses 5-core twisted shielded cable transmission, effectively resisting electromagnetic interference in industrial sites and supporting long-distance transmission and multi-node networking.

• Convenient Installation Design: 3/4 NPT pipe thread interface supports submerged, pipeline or tank installation. During installation, the sensor bottom should be at least 5cm from the container bottom and at least 2cm from the side wall to ensure measurement accuracy.

• Low Power Consumption Operation: Power consumption is only 0.2W@12V, suitable for continuous online operation and reducing overall system energy consumption. The two-point calibration method is easy to operate, with stable and reliable calibration parameters.

These technical features make the NBL-DDM-406-S a reliable choice for high-salinity water online monitoring, ensuring data continuity and accuracy while simplifying engineering integration and later maintenance.

NBL-DDM-406-S Online Salinity Sensor Technical Specifications

NBL-DDM-406-S Online Salinity Sensor Application Scenarios

1. Seawater Aquaculture Intelligent Management: Real-time monitoring of salinity in breeding ponds, combined with temperature data to optimize the breeding environment and ensure healthy growth of fish, shrimp and other organisms.

2. Seawater Desalination and Water Supply Systems: Monitoring salinity changes in raw seawater and during the desalination process to assist process control and effluent quality assurance.

3. Industrial High-Salt Wastewater Treatment: Online salinity monitoring for high-salt wastewater in chemical, petroleum, pharmaceutical and other industries to support process adjustment and compliant discharge.

4. Marine Environment and Nearshore Monitoring: Submerged installation in marine and estuary areas to achieve continuous online collection of salinity, assisting in environmental scientific research and pollution monitoring.

5. Industrial Circulating Cooling Water and Boiler Water Treatment: Monitoring water salinity to prevent scaling and corrosion and extend equipment service life.

Wiring and Installation Instructions

During installation, the sensor should be kept vertical or properly tilted. During testing, keep at least 5cm from the bottom of the container and at least 2cm from the side wall to avoid interference from walls or the bottom. It supports submerged installation and can also be used in pipelines or tanks (side wall installation is recommended with a dedicated mounting base).

Electrical Connection (5-core twisted shielded cable):

• Red wire → Power positive (12～24VDC)

• Black wire → Ground (GND)

• Blue wire → 485A

• Green wire → 485B

• Yellow wire → 4-20mA current output (optional, leave floating if not in use)

Before powering on, please carefully check the wire sequence. All wiring points must undergo strict waterproof sealing treatment, and cables with certain corrosion resistance should be selected to adapt to seawater or long-term humid environments.

FAQ

Q1: What measurement principle does the NBL-DDM-406-S use?

A: The product uses the inductive electrode method with a non-contact measurement approach, effectively reducing electrode pollution and corrosion, making it suitable for long-term online monitoring in high-salinity water bodies.

Q2: Does the sensor support temperature compensation?

A: Yes. It has a built-in Pt1000 temperature sensor that realizes automatic temperature compensation, ensuring that salinity measurement accuracy is not affected by temperature within the 0～50℃ operating range.

Q3: How does the RS485 Modbus protocol help system integration?

A: The sensor strictly follows the Modbus RTU standard and can be directly connected to PLC, DCS, SCADA or IoT platforms. It supports multi-node networking, has strong anti-interference capability, and is easy to integrate.

Q4: How is the corrosion resistance when used in seawater?

A: The housing is a combination of ABS and TC4 titanium alloy, with excellent seawater corrosion resistance. The IP68 protection rating supports long-term immersion in high-salinity environments.

Q5: Is the calibration operation complicated?

A: It uses two-point calibration (zero point calibration + slope calibration), which is easy to operate. Zero point calibration is performed in air, and slope calibration is completed by placing the sensor in standard solution.

Q6: What are the distance requirements during installation?

A: During installation and testing, the sensor should be at least 5cm from the bottom of the container and at least 2cm from the side wall to ensure the measurement area is not interfered with and data is more accurate.

Q7: Does it support 4-20mA analog output?

A: Yes. Optional 4-20mA current output is available and can be used together with RS-485 digital output to meet the access requirements of different control systems.

Q8: What is the product warranty period?

A: One-year warranty service is provided from the date of sale (excluding man-made damage). The sensor uses high-quality materials, has a long designed service life, and has low maintenance requirements.

Summary

The NiuBoL NBL-DDM-406-S online salinity sensor provides a professional and stable engineering solution for high-salinity water online monitoring with its inductive electrode technology, automatic temperature compensation and high-corrosion-resistant materials. It helps system integrators and engineering contractors achieve reliable continuous salinity monitoring in seawater aquaculture, seawater desalination, industrial water treatment and other fields, reducing operation and maintenance costs and improving overall system reliability.

If you are planning a salinity monitoring project or need customized technical support for seawater or high-salt working conditions, please feel free to contact the NiuBoL professional team. We will provide detailed product selection guidance, installation and commissioning suggestions, and long-term stable supply assurance to jointly build an efficient and reliable water quality monitoring system.

NBL-DDM-406-S Industrial-grade Online Salinity Sensor Data Sheet

NBL-DDM-406-S Industrial-grade Online Salinity Sensor.pdf