Nitrate Nitrogen Digital Sensor:NO3-201

Q: What are the mandatory requirements for installing NO3-201 online nitrate and nitrogen sensors?

The sensor should not be installed upside down or horizontally. During installation, it is necessary to ensure that the inclination is ≥ 15 ° to ensure that the internal reference liquid leaks out normally; The installation position should avoid dead zones of water flow and areas with dense bubbles to prevent interference with measurement accuracy. It also supports various installation methods such as immersion, pipeline, tank, etc. that are compatible with 3/4NPT pipe threads.

Q: <strong>How often does the sensor need to be calibrated, and what are the prerequisites and operational points for calibration?</strong>

The sensor has undergone professional calibration before leaving the factory. If the measurement data deviation exceeds the accuracy standard of ± 10% or ± 2mg/L, there is no need for frequent calibration; Calibration requires two-point calibration (zero point+slope). Place the sensor in the corresponding standard solution and let it stand for 5 minutes. After the value stabilizes, issue the calibration command. After calibration, verify the measurement accuracy.

Q: <strong>What is the warranty period for electrodes, what is their lifespan under normal use, and can they be replaced with separate parts if damaged?</strong>

Electrodes are consumables and the official provides a six-month warranty service; Using a patented reference system, the lifespan under normal use is better than that of ordinary industrial nitrate nitrogen electrodes; The electrode membrane cap can be disassembled and replaced separately, without the need to replace the sensor as a whole, effectively reducing maintenance costs in the later stage.

The NO3-201 integrated online nitrate nitrogen digital sensor was made to measure the concentration of nitrate ions in water bodies online. It uses the idea of a PVC membrane nitrate ion selective electrode and has automated temperature correction using Pt1000. It is good for many uses, such as aquaculture, environmental monitoring, and water treatment, because it has stable measurements, is easy to install, and works with a wide range of devices. It is a cheap way to keep an eye on nitrate nitrogen online.

★★★★★

Short delivery time
Better price
Customizable parameters

Parameters

Parameter Item	Technical Index
Measuring Range	0~100.0mg/L (Resolution: 0.1mg/L), 0~1000.0mg/L (Resolution: 0.1mg/L)
Measuring Accuracy	±10% or ±2mg/L; Temperature Accuracy: ±0.5℃
Operating Environment	Temperature: 0~40℃, Pressure: <0.1MPa, pH Range: 2.5~11pH
Storage Temperature	-5~40℃
Power Supply	12~24VDC, Power Consumption: 0.2W@12V
Signal Output	RS-485 (Modbus/RTU), Default: 9600, n, 8, 1
Housing Material	316L Stainless Steel
Protection Grade	IP68
Mounting Method	3/4NPT Pipe Thread, Immersion Mounting (Inclined ≥15° required)
Cable Configuration	Standard: 5m 4-core Twisted Shielded Cable, Customizable Length
Calibration Method	Two-point Calibration (Zero Point + Slope)
Temperature Compensation	Automatic Temperature Compensation (Pt1000)
Power Consumption	0.2W@12V
Interfere Resistance	With anti-interference design for common ions

Why choose this digital sensor?

Patented nitrate electrode with Pt1000 automatic temperature regulation, anti-interference for common ions, stable measurement and long life.
Flexible installation & strong compatibility: 3/4NPT thread, multiple mounting ways; Modbus/RTU protocol, dockable with PLC/DCS.
Easy maintenance & low cost: Replaceable membrane cap, no frequent calibration needed.
High protection & durable: IP68 rating, 316L stainless steel housing, corrosion-resistant for long-term immersion.

Featured Applications

Municipal sewage treatment: online monitoring of nitrate and nitrogen throughout the entire process to ensure that the effluent meets the discharge standards
Industrial wastewater monitoring: Real time detection of nitrate and nitrogen in wastewater from chemical, food and other industries to meet control requirements
Aquaculture: Monitoring of nitrate and nitrogen in freshwater/seawater aquaculture, providing data support for water quality control and yield increase
Environmental monitoring: Long term monitoring of nitrate and nitrogen in rivers, lakes, and groundwater to assist in water ecological protection

Installation and wiring

Installation requirements

Inverted/horizontal installation is prohibited. The sensor should be installed at an angle of ≥ 15 ° to ensure normal leakage of the reference solution;
Support installation methods such as top insertion, circulation, pipeline, and sinking. The installation location should avoid dead zones and areas with dense bubbles to prevent measurement interference.

Electrical wiring (4-core twisted pair shielded wire)

Red line: power cord (12~24VDC)
Black wire: Ground wire (GND)
Blue line: 485A
White line: 485B

Waterproof treatment should be done at the wiring points, and external cables for users should have anti-corrosion capabilities to avoid cable aging in immersion/exposure environments.

Maintenance

Soak the electrode in tap water for 24 hours before use, and dry and protect the sensing element;
Rinse the electrode with distilled water in daily life, absorb dry water and do not wipe to avoid damaging the membrane body;
Long term storage requires washing and drying the electrodes, placing them in their original packaging, and keeping them away from distilled water, protein solutions, and organic silicone oils;
Wipe and dry the contaminated wiring terminals with anhydrous alcohol, and perform two-point calibration when the measurement error exceeds the limit;
The sediment attached to the membrane cap can be washed away. If it still cannot be calibrated after maintenance, replace the membrane cap/electrode.

Technical Support

The sensor should not be installed upside down or horizontally. During installation, it is necessary to ensure that the inclination is ≥ 15 ° to ensure that the internal reference liquid leaks out normally; The installation position should avoid dead zones of water flow and areas with dense bubbles to prevent interference with measurement accuracy. It also supports various installation methods such as immersion, pipeline, tank, etc. that are compatible with 3/4NPT pipe threads.

The sensor has undergone professional calibration before leaving the factory. If the measurement data deviation exceeds the accuracy standard of ± 10% or ± 2mg/L, there is no need for frequent calibration; Calibration requires two-point calibration (zero point+slope). Place the sensor in the corresponding standard solution and let it stand for 5 minutes. After the value stabilizes, issue the calibration command. After calibration, verify the measurement accuracy.

Electrodes are consumables and the official provides a six-month warranty service; Using a patented reference system, the lifespan under normal use is better than that of ordinary industrial nitrate nitrogen electrodes; The electrode membrane cap can be disassembled and replaced separately, without the need to replace the sensor as a whole, effectively reducing maintenance costs in the later stage.

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Due to its stable measurement performance, flexible installation method, and easy maintenance, the NO3-201 online nitrate nitrogen sensor can meet the online monitoring needs of water bodies in multiple scenarios, providing accurate and reliable real-time data for water quality control, standard discharge, and ecological protection. We will provide comprehensive technical assistance and after-sales service to help customers implement water quality monitoring in diverse industries and protect the water environment.

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