LoRaWAN nitrite ion transmitter, designed specifically for online monitoring of water quality. Adopting PVC membrane ion selective electrode, with a range of 0-2 mg/L, resolution of 0.001 mg/L, accuracy of ± 5%, and integrated Pt1000 automatic temperature compensation. Supports LoRaWAN wireless communication (OTAA Class A/C), with a default reporting period of 10 minutes, long transmission distance, and flexible networking. Widely applicable for detecting nitrite concentration in industrial wastewater, surface water, drinking water, and agricultural process control. The electrode has a lifespan of 1-2 years, supports zero point, slope, and temperature calibration, and is easy to maintain. The equipment is powered by a wide voltage range (DC10-28V), with flexible installation methods, to assist in remote intelligent monitoring of water quality.