NBL-WQ-NHN Online Water Quality Ammonia Nitrogen Sensor

The online ammonia nitrogen water quality integrated sensor NBL-WQ-NHN is manufactured using an ammonium ion-selective electrode based on a PVC membrane to measure ammonium ion content in water with temperature compensation, ensuring fast, simple, accurate, and economical testing. The technical parameters, maintenance, and communication protocols of the ammonia nitrogen sensor are described in detail in this user manual. Signal output: RS-485 bus, Modbus/RTU protocol, convenient for connection to PLC, DCS, industrial control computer, general controller, paperless recorder, touch screen display, and other third-party equipment. 

The patented ammonium ion probe, with an internal reference solution, slowly exudes through a microporous salt bridge under a pressure of at least 100 kPa (1 bar). This reference system is highly stable and provides a longer electrode service life than conventional industrial electrodes. Easy installation: 3/4 NPT thread for easy submersible installation or installation in pipes and tanks. Protection level IP68.

Technical Specifications of Water Quality Ammonia Nitrogen Sensor NBL-WQ-NHN

1. Application environment

The integrated online ammonia nitrogen water quality sensor NHN-206A is manufactured using an ammonium ion-selective electrode based on a PVC membrane to measure ammonium ion content in water with temperature compensation, ensuring fast, simple, accurate, and economical testing. The technical parameters, maintenance, and communication protocols of the ammonia nitrogen sensor are described in detail in this user manual.

Signal output: RS-485 bus, Modbus/RTU protocol, convenient for connection to PLC, DCS, industrial control computer, general controller, paperless recorder, touch screen display, and other third-party equipment.

The patented ammonium ion probe, with an internal reference solution, slowly exudes through a microporous salt bridge under a pressure of at least 100 kPa (1 bar). This reference system is highly stable and provides a longer electrode service life than conventional industrial electrodes.

Easy installation: 3/4 NPT thread for easy submersible installation or installation in pipes and tanks.

Protection level IP68.

2. Electrical connection

a) Red wire - Power supply (12 ~ 24 V)

b) Black wire - Ground (GND)

c) Blue wire - 485A

d) White wire - 485B

After wiring is completed, carefully check to avoid incorrect connections before powering on.

Cable specification: Since the cable is immersed in water (including seawater) for long periods or exposed to air, all connection points must be waterproofed. The user cable must have corrosion resistance.

3. Maintenance

1. Use and maintenance

Rinse the electrode in distilled water (or deionized water), dry it with a cloth, and do not rub it dry. Place the electrode in the electrode holder. Before use, immerse the electrode tip in distilled water (or deionized water) for 10 minutes, then immerse it in a diluted ammonium ion solution for 2 hours.

Keep the electrode dry before use. The sensitive element should be stored in the protective bottle. The electrode must be activated in a conditioning solution for 24 hours before testing. If stored overnight or longer, rinse with deionized water, dry, and store in the original packaging.

Check whether the terminal is dry. If contaminated, clean with absolute ethanol and dry it. Avoid long-term immersion in distilled water or protein solutions and avoid silicone grease contact. For long-used electrodes, the PVC membrane may become translucent or develop deposits, which can be rinsed with distilled or deionized water. If measurement errors occur after long-term use, recalibrate the meter.

If calibration and measurement cannot be performed even after proper maintenance, the electrode has failed and should be replaced.

Major interfering ions are shown below:

Concentration of interfering ions that causes 10% error at different ammonium ion concentrations

4. Sensor calibration

Note: The sensor is calibrated before leaving the factory. If measurement error is not exceeded, it should not be arbitrarily recalibrated.

a) Zero calibration

Place the sensor in a vial containing zero standard solution and wait 5 minutes. Once the value stabilizes, check if it is within the error range. If not, perform zero calibration. Refer to the appendix for calibration instructions.

b) Slope calibration

Place the sensor in a vial containing slope standard solution and wait 5 minutes. Once the value stabilizes, check if it is within the error range. If not, slope calibration is required. Refer to the appendix for calibration instructions.

NBL-WQ-NHN Ammonia Nitrogen Water Quality Sensor Datasheet.pdf

NBL-WQ-NHN Ammonia Nitrogen Water Quality Sensor.pdf