Yexsensor YEX-NHN-406 Online Ammonium Nitrogen Sensor: High Reliability Ion Selective Electrode Monitoring Terminal

In modern industrial wastewater treatment, environmental water quality monitoring and smart agriculture systems, real-time acquisition of ammonium nitrogen concentration data is the core link for optimizing denitrification processes and assessing the risk of water eutrophication. Yexsensor YEX-NHN-406 series online ammonium nitrogen sensor, based on advanced ion selective electrode (ISE) method, provides system integrators and environmental engineering contractors with an in-situ monitoring solution that combines economy and industrial-grade stability.

Compared with traditional large wet chemical analyzers, YEX-NHN-406 does not consume reagents, shortens the response time to the second level, and with its unique reference system design, it demonstrates excellent durability in harsh industrial application scenarios.

YEX-NHN-406 Online Ammonium Nitrogen Sensor Core Working Principle: Ion Selectivity Technology and Patented Reference System

1. Ion Selective Membrane (PVC Membrane)
   The core sensing element of YEX-NHN-406 is a PVC sensitive membrane based on patented formula. When the sensor is immersed in the solution to be measured, the ammonium ion potential difference on both sides of the membrane follows the Nernst Equation. By accurately measuring the potential difference between the working electrode and the reference electrode, and combining the compensation algorithm of the built-in temperature sensor, the sensor can convert the electrical signal into high-precision concentration values in real time.

2. Pressure Compensated Salt Bridge System
   The main reason why traditional electrodes fail easily in industrial sites is the loss or contamination of the reference solution. Yexsensor adopts a patented reference system design, in which the internal reference liquid is driven by a pressure of not less than 100 KPa and slowly seeps out through the microporous salt bridge. This positive pressure design effectively prevents the reverse permeation of external wastewater, ensures the high stability of the reference potential, and makes the electrode life far exceed that of ordinary industrial-grade products.

YEX-NHN-406 Online Ammonium Nitrogen Sensor Technical Performance Indicators and Selection Specifications

YEX-NHN-406 provides two configurations: Type A (general type) and Type S (industrial enhanced type) to meet the material compatibility and protection requirements under different working conditions.

1. Technical Parameters Table

2. Hardware and Electrical Specifications

System Integration and Deployment Engineering Guide

1. Digital Architecture Design
   YEX-NHN-406 supports native RS-485 Modbus RTU communication, which allows system integrators to easily mount the probe onto various industrial buses. Digital signal output avoids attenuation and noise interference caused by long-distance analog transmission.

2. Electrical Connection Specification

• Red (VCC): Power positive pole (12～24V DC)

• Black (GND): Power ground wire

• Blue (485A): Signal A

• Green (485B): Signal B

• Yellow (I-Out): 4-20 mA current output (optional item)

3. Installation Posture Requirements
   Key tip: The sensor is strictly prohibited from being installed upside down or horizontally. During on-site deployment, it must be installed with a tilt angle of at least 15 degrees. This tilt design helps the pressure conduction of the liquid inside the electrode and prevents air bubbles from adhering to the sensing membrane surface, thereby avoiding data drift.

YEX-NHN-406 Online Ammonium Nitrogen Sensor Typical Application Scenarios

• Municipal Wastewater Treatment: Real-time monitoring of ammonium nitrogen concentration in nitrification/denitrification processes to optimize aeration energy consumption.

• Industrial Wastewater Monitoring: Online monitoring of compliance at discharge outlets of petrochemical, leather and fertilizer production enterprises.

• Aquaculture: Real-time early warning of ammonia nitrogen toxicity in high-density aquaculture environments.

• Surface Water Monitoring: Integrated multi-parameter acquisition for river and lake monitoring buoys.

• Smart Irrigation: Precise regulation of nutrient components in agricultural irrigation water.

Maintenance and Anti-Interference Strategies

1. Activation and Storage
   Before testing, remove the protective sleeves of the measuring electrode and reference electrode, and soak them in clean water for 2 hours to complete electrode activation. When not in use for a long time, ensure that the electrode is stored dry and put back the sensing element protective cap.

2. Interfering Ion Analysis
   Ion selective electrodes are subject to competitive interference from ions such as potassium (K+) and sodium (Na+) in specific environments.

Frequently Asked Questions (FAQ)

Q1: Can the YEX-NHN-406 sensor test ammonia nitrogen?

A1: This sensor measures ammonium ions (NH₄⁺). Under specific pH conditions, there is a dynamic equilibrium between ammonium ions and molecular ammonia. By combining pH value, the total ammonia nitrogen content can be calculated.

Q2: Why must the installation be tilted by 15 degrees?

A2: Tilted installation ensures that the reference liquid inside the electrode is always pressed toward the sensitive membrane side, while avoiding air bubbles gathering on the measurement window. This is a technical requirement to ensure that long-term monitoring data does not drift significantly.

Q3: Will the discoloration of the sensor's PVC sensing membrane affect the measurement?

A3: After long-term use, the PVC membrane may become translucent or have deposits attached, which is a normal phenomenon. At this time, rinse with deionized water. If it still cannot measure normally after rinsing and recalibration, the sensing module needs to be replaced.

Q4: Can the sensor withstand high-pressure flushing?

A4: The maximum pressure bearing capacity of the sensor is 0.1 MPa. During cleaning, it is recommended to use spray or soft cloth wiping, and avoid direct impact of high-pressure water column on the sensitive membrane.

Q5: How to deal with severe potassium ion interference?

A5: If the potassium ion background value is extremely high in the application environment (such as certain specific fertilizer wastewater), it is recommended to optimize the compensation algorithm at the system integration end, or consult the Yexsensor technical department for correction solutions under specific working conditions.

Q6: Why must the electrode be activated before measurement?

A6: The ion selective membrane needs to establish a stable hydration layer through soaking. Electrodes that have not been fully activated respond slowly and have unstable values.

Q7: Can the Modbus address output by the sensor be modified?

A7: Yes. Through standard Modbus commands, users can modify the slave ID and baud rate of the sensor, which is convenient for integrating multiple probes on the same 485 bus.

Q8: What is the approximate life of the reference electrode?

A8: Thanks to the 100 KPa positive pressure salt bridge technology, in normal surface water or neutral sewage, the electrode life can usually reach 12-24 months, which is far better than conventional ISE electrodes.

Summary

Yexsensor YEX-NHN-406 is an online ammonium nitrogen sensing core specially designed for engineering integration. It not only solves the problems of large size and high maintenance of traditional analyzers, but also improves the stability of ion selective electrodes in complex industrial fluids through patented reference structure design. For system integrators who pursue low full life cycle cost and high data real-time performance, it is an ideal choice for digital water monitoring stations.