Apogee S2-412-SS downward-looking SDI-12 NDVI sensor

Product detailed description

Get precise data on the health of your crop

The S2-412-SS sensor is a top-class tool for precise measurement of the health and density of plant cover. Using the normalised difference vegetation index (NDVI), you obtain objective data that are key for precision agriculture, scientific research and advanced vegetation monitoring, including demanding annual plants.

How does the sensor work?

The sensor measures reflected sunlight in two specific bands: red (Red, 650 nm) and near-infrared (NIR, 810 nm). Healthy, vital plants with a high chlorophyll content absorb most red light for photosynthesis and strongly reflect near-infrared light.

From these two values, the sensor calculates the NDVI index according to the formula (NIR - Red) / (NIR + Red). A high NDVI value indicates dense and healthy vegetation, while low values may signal plant stress, pest infestation, disease or a lack of nutrients.

Key features and benefits

• Precise NDVI measurement: You obtain objective data for informed decisions on irrigation, fertilisation or plant protection.
• Digital SDI-12 output: The standardised protocol ensures easy integration with data loggers and control systems.
• Extreme durability: Fully potted electronics in an anodised aluminium body with IP68 protection guarantee reliable operation even in the most demanding conditions.
• Self-cleaning design: The domed shape of the sensor head reduces dirt build-up and water run-off, which minimises maintenance requirements.
• Low energy consumption: Thanks to a current draw of just 1.3 mA, the sensor is ideal for long-term field installations powered by batteries or solar panels.
• Four-year warranty: The warranty against defects in material and workmanship is proof of high quality and reliability.

Typical uses of the sensor

This sensor is an invaluable helper for a wide range of applications. In agriculture, it allows you to monitor the condition of crops such as tomatoes, peppers or strawberries and optimise agrotechnical interventions. In research, it is used to track phenological stages (budburst in spring, ageing in autumn), assess the impacts of drought, research ecosystems, estimate leaf area (LAI) and for many other purposes.

Parameters

• Output: Digital, SDI-12 v1.3 protocol
• Input voltage: 4.5 to 28 V DC
• Current draw: 1.1 mA (idle state), 1.3 mA (active)
• Response time: < 1 s
• Field of view (FOV): 32.2° (pointing downwards)
• Measured wavelength bands: 650 nm (width 20 nm), 810 nm (width 20 nm)
• Calibration uncertainty: ± 10 %
• Measurement repeatability: < 1 %
• Long-term drift: < 2 % per year
• Operating environment: temperature -40 to 70 °C, relative humidity 0 to 100 %
• Dimensions: diameter 2.4 cm, height 2.75 cm
• Weight: 100 g (including 5 m cable)
• Cable: 5 m shielded twisted pair, Santoprene sheath, stainless steel connector
• Protection: IP68
• Warranty: 4 years