NH3-N Water Analyzer | Online Ammonia Nitrogen Monitoring Analyzer

This online NH3-N water analyzer continuously measures ammonia nitrogen in drinking water, surface water and industrial wastewater. It adopts spectrophotometry / ion-selective electrode (ISE) principle, supports automatic calibration & cleaning, 4–20mA + RS485 output, and is widely used in unattended water quality monitoring stations and process control.

This online NH3-N (ammonia nitrogen) analyzer provides realtime, continuous monitoring of ammoniumnitrogen concentration in aqueous matrices. Two measurement principles are available to suit different water quality:

Spectrophotometric version (high accuracy): Nessler's reagent or salicylate method, colorimetric detection at specific wavelength, suitable for low-level drinking water/surface water and discharge compliance monitoring.

ISE electrode version (low maintenance): Ammonia selective electrode measurement, reagent-free or micro-reagent, fast response, ideal for industrial wastewater and process control.

The integrated system includes automatic sampling, filtering, dosing, reaction, cleaning and calibration modules, reducing manual intervention. It supports 2/4–20mA analog, RS485 Modbus-RTU, relay alarm, and data logging. The waterproof cabinet (IP65) enables outdoor installation in monitoring stations, pump stations and treatment plants.

The sensor measures ammonia nitrogen concentration using the ion-selective electrode method. The ammonia nitrogen ion-selective electrode directly detects ammonium ions in water to determine the ammonia nitrogen concentration. A pH electrode is used as a reference electrode for improved stability. Since the sensor's measurements can be affected by potassium ions, potassium ion compensation is required when the potassium ion concentration in water is high.

The ammonia nitrogen sensor integrates an ammonium ion-selective electrode, potassium ion electrode (optional), pH electrode, and temperature electrode into a single unit. These parameters can mutually correct and compensate for the ammonia nitrogen measurement while enabling multi-parameter measurement.

NH3-N Analyzer for Industrial Wastewater001

Sensor Technical Specifications

Measurement Range	NH4N: 0.1~ 3000 mg/L K+: 0.5~5000 mg/L (optional) PH: 5-10 Temperature: 0-40℃
Resolution	NH4N: 0.01 mg/L K+: 0.01 mg/L(optional) Temperature: 0.1℃ pH: 0.01
Accuracy	NH4N: NH4-N: ±5% of reading or ±0.2 mg/L, whichever is greater K+: ±10% of reading or ±0.2 mg/L (optional) Temperature: ±0.5℃ pH: ±0.1 pH
Repeatability	±5% or 0.2 mg/L, whichever is greater
Communication Protocol	MODBUS RS485
Storage Temperature	0 to 50°C (non-freezing)
Operating Temperature	0 to 40°C (non-freezing)
Dimensions	55mm×342mm(diameter × length)
Weight	<1KG
Protection Rating	IP68/NEMA6P
Cable Length	Standard 10 m cable, extendable up to 100 m

Controller Technical Specifications

Display Output	128×64 graphic dot-matrix LCD with LED backlight for sunlight-readable operation
Power Supply	AC: 85–500 VAC; DC: 9–36 VDC
Main Material	PA66+GF25+FR(Top cover);Aluminum alloy powder coating (lower shell)
Output	Three channels of 4-20mA
Relay	Three relays, programmable for response parameters and values
Digital Communication	MODBUS RS485 for real-time data transmission
Storage Temperature	-20 or 70℃
Operating Temperature	-15 or 60℃
Waterproof Ratin	IP66/NEMA4X
Dimensions	145mm125mm162mm (L × W × H)
Weight	1.35KG

Features

Digital sensor with strong anti-interference capability and long-distance signal transmission.
Standard digital signal output allows integration and networking with other devices without a transmitter.
Easy and quick on-site installation, plug-and-play.
Reverse polarity protection for power supply and misconnection protection for RS485 A/B terminals.
Simple operation with reliable results; intuitive interface reduces operational errors.
Visual alarm system provides critical warning functions.
The controller supports wall-mounted, panel-mounted, or tube-clamp installation.

NH3-N Analyzer for Wastewater Treatment Plant001

Typical Applications

Monitoring ammonia nitrogen levels in nitrification treatment and aeration tanks of wastewater treatment plants, industrial processes, and river water.