The Digital Eye of Smart Water Management: Yexsensor YEX-ZS-406-A Online Turbidity Sensor

In modern water treatment and industrial process control, turbidity is a core indicator for measuring water clarity, evaluating filtration efficiency, and ensuring process safety. The YEX-ZS-406-A integrated online turbidity sensor developed by Yexsensor integrates cutting-edge optical sensing technology and digital communication protocols, providing global system integrators with a high-precision, low-maintenance, and easy-to-deploy industrial-grade water quality monitoring tool.

Leading Optical Measurement Architecture

1. Based on 90° Scattered Light Principle

YEX-ZS-406-A strictly follows the international standard scattered light measurement method. When an infrared beam enters the water sample to be measured, suspended particles in the water cause light scattering. The sensor accurately captures the intensity of scattered light at a 90° angle to the incident light direction and combines it with internal preset calibration algorithms to achieve high-sensitivity conversion of turbidity (NTU) in water. This design effectively filters background light interference and ensures measurement accuracy at low ranges.

2. Optical Fiber Structure and Infrared LED Light Source

Anti-interference capability: The specially designed optical fiber structure greatly enhances the sensor's shielding ability against external ambient stray light, allowing stable operation even in open water tanks.

High-stability light source: Built-in infrared LED cold light source with extremely stable luminous flux output, which not only extends the service life of the equipment but also reduces measurement temperature drift caused by light source attenuation.

3. Fully Digital Communication Interface

The sensor has a built-in signal conversion circuit and supports the standard RS-485 (Modbus RTU) protocol. This enables the YEX-ZS-406-A to be directly integrated into digital factory architectures, achieving multi-sensor networking without complex analog conversion, greatly simplifying system wiring and later debugging.

Yexsensor YEX-ZS-406-A Online Turbidity Sensor Detailed Technical Specifications

Yexsensor YEX-ZS-406-A Online Turbidity Sensor Application Scenarios

1. Tap Water Plant Filtration Monitoring and Finished Water Quality Control

In drinking water treatment processes, turbidity is an important indicator for evaluating filter operation status. The 0-20 NTU low-range version of the YEX-ZS-406-A features ultra-high resolution of 0.01 NTU. It can be installed in post-filter water and finished water pipelines to monitor filtration effectiveness in real time and ensure effluent meets hygiene standards.

2. Wastewater Treatment Plant Effluent Discharge Compliance Monitoring

Wastewater treatment plants require strict monitoring of suspended solids concentration at the final discharge outlet. This sensor features IP68 protection and strong anti-fouling capability, enabling it to adapt to complex discharge environments and assist management personnel in real-time control of process discharge compliance.

3. Industrial Cooling Circulating Water and Process Control

In power, steel, and chemical industries, an increase in cooling circulating water turbidity indicates risks of heat exchanger leakage or system scaling. The RS485 output of the YEX-ZS-406-A can be directly connected to DCS systems to achieve automatic blowdown and water replenishment control, reducing system operation risks.

4. Environmental Monitoring and Smart River Channels

Thanks to its low-power design and IP68 protection, this sensor is ideal for integration into solar-powered buoy monitoring stations for long-term online turbidity monitoring of surface water, lakes, and river channels, providing underlying data support for smart environmental protection.

Installation and Wiring Specifications

Physical Installation Requirements

To ensure the measurement window is not affected by side wall interference and to obtain representative water samples, please follow these spacing recommendations:

• Wall distance: The sensor probe should maintain a distance of more than 5cm from the side wall of the measurement container.

• Bottom distance: The sensor measurement end face should maintain a distance of more than 10cm from the bottom.

• Installation method: Submersible installation, fixed on brackets or pipelines using 3/4 NPT thread.

Digital Wiring Guidelines

Use 5-core twisted shielded cable to effectively resist electromagnetic interference in industrial sites:

• Red wire: Power positive (12～24VDC)

• Black wire: Power negative (GND)

• Blue wire: 485A

• White wire: 485B

• Yellow wire: Current output (optional; if not enabled, leave suspended and perform waterproof treatment)

Yexsensor YEX-ZS-406-A Online Turbidity Sensor Maintenance and Calibration Guide

1. Daily Maintenance Procedures

The cleanliness of the measurement window is the lifeline for ensuring accurate readings.

Surface cleaning: Rinse the sensor housing with tap water. For stubborn dirt on the measurement window, it is recommended to use a damp soft cloth with a small amount of household detergent and gently wipe. Never use rough objects to scrape.

Cable inspection: Ensure the cable is in a relaxed state to avoid long-term tension causing internal wire breakage.

2. Digital Two-Point Calibration

When regulatory requirements or environmental factors cause reading deviations to exceed the error range, calibration is required:

• Zero point calibration: Place the sensor in zero-turbidity liquid, ensure it is more than 10cm above the bottom of the container, and write the zero position via communication command after stabilization.

• Slope calibration: Place the sensor in the corresponding turbidity standard solution, and execute the slope correction command after stabilization.

Frequently Asked Questions (FAQ)

Q1: Does the Yexsensor YEX-ZS-406-A support operation in seawater?

Answer: The sensor housing is made of POM and ABS materials, offering good corrosion resistance and can be used in ordinary seawater or high-salinity environments. However, it is recommended to apply additional waterproof and anti-corrosion treatment at the wiring connections and regularly clean the measurement window to prevent biological attachment.

Q2: Why can't my controller display the measurement results?

Answer: First, check whether the wiring sequence is correct, especially the power polarity and whether the RS485 A/B wires are reversed. Also, check whether the communication parameters (such as baud rate and device address) are consistent with the factory settings of the sensor.

Q3: Can the sensor's response speed meet automatic control requirements?

Answer: The T90 response time of the YEX-ZS-406-A is less than 30 seconds. For most water treatment blowdown and dosing linkage control, this speed can fully meet real-time feedback requirements.

Q4: Does this sensor need to be paired with a dedicated display instrument?

Answer: Not necessarily. Since it supports the standard Modbus RTU protocol, it can be directly connected to PLC or industrial host computers. Of course, Yexsensor also provides supporting multi-parameter controllers for convenient on-site data viewing.

Q5: What causes large and continuous fluctuations in measured values?

Answer: There are usually two reasons: first, foreign matter or air bubbles are attached to the sensor measurement window — please clean the window; second, the installation position is improper, such as being too close to the container wall causing background light reflection — please ensure the probe maintains more than 5cm distance from the side wall.

Q6: What is the maximum submersion depth supported by the sensor?

Answer: This product has an IP68 protection rating and is designed with redundancy to support long-term submersion in environments up to 20 meters water depth.

Q7: What is the function of the built-in temperature sensor?

Answer: The temperature sensor (Pt1000) is mainly used for automatic temperature compensation. Because the optical properties of liquids and the response of electronic circuits are affected by temperature, the real-time temperature compensation algorithm ensures the sensor provides consistent readings within the 0-50°C range.

Q8: Can the sensor be installed horizontally?

Answer: Vertical installation is recommended. Horizontal installation may cause sediment or air bubbles to accumulate on the measurement window, affecting the optical path. If horizontal installation is necessary, please ensure the fluid flow rate is sufficient to remove deposits from the window surface.

Quality Commitment and Professional Service

Yexsensor always adheres to the principle of "Quality First". Every YEX-ZS-406-A undergoes rigorous 72-hour aging tests and stability verification before leaving the factory. We promise to provide a one-year after-sales warranty from the date of sale (excluding man-made damage).

Standard Packing List:

• YEX-ZS-406-A sensor × 1

• 5-meter high-quality shielded cable × 1

• Product certificate and paper manual