Introduction
The document discusses the stationary water quality monitoring system using the nitrate probe SPS-NO3, designed for measuring nitrate concentrations in water. It highlights the increasing nitrate pollution in groundwater due to agricultural practices and the need for high-resolution monitoring.

Specifications
The SPS-NO3 is a robust, low-maintenance probe made of stainless steel, suitable for observation wells with a diameter starting from 3 inches. It offers high measuring accuracy with minimal drift, requiring only annual calibration verification. The probe is available in different measuring ranges up to 266 mg/L NO3- and connects via RS 485 for data logging.

Measuring Principle
The probe uses a xenon lamp and photodiode to perform optical measurements at specific wavelengths, allowing for precise nitrate concentration calculations. It compensates for organic compounds and turbidity, ensuring accurate measurements.

Optimized Measuring Ranges
The SPS-NO3 offers three path lengths (1 mm, 2 mm, 5 mm) with corresponding measuring ranges, allowing for optimal selection based on expected nitrate concentrations.

Accessories
An optional cleaning module with a wiper is available to maintain the cleanliness of the measuring window, configurable via SEBAConfig software.

Protective Housing and Data Logger
The probe is housed in a robust aluminum protective housing with space for a data logger and energy supply. The SEBA water quality station uses the UnilogCom data logger, featuring a 32-bit microcontroller, 16 MB ring buffer, and 32 input channels. It supports data transmission via a 4G modem and can send alarm messages via SMS.

Operating and Power Supply
The system can be operated via USB or Bluetooth and is powered by a rechargeable battery, with an option to extend runtime using a solar panel.

Modular Sensor Concept
The system supports additional SEBA probes, such as the multi-parameter probe MPS-D8 and the pressure/temperature probe DS(T) 22, for comprehensive water quality monitoring.

Technical Data
The probe features a xenon flashlight, multiple photo diodes, and offers various measurement ranges and accuracies depending on the path length. It operates under specific temperature and pressure conditions and is protected by an IP 68 rating.

Advantages
The SPS-NO3 offers high measurement accuracy with low operating costs, minimal calibration needs, and compatibility with SEBA data loggers, making it a cost-effective solution for nitrate monitoring.