SenseUVI

This App senses 200-370nm wavelength UV light and gives an analogue output between 0-1V proportional to the UV Index.

Directions

Setup

Plug the Analogue Ultraviolet (UV) sensor into P5; navigate to the SenseUVI app on the Kookaberry’s menu and press Button B to run

Running the app

What is showing on the screen?

1. Top Row: Name of app; ID of Kookaberry (01); Pin for connection of peripheral (P5)
2. Second Row: Graphical representation of analogue input from 0 to 1V; UV Index (0 to 11)
3. Third Row: Value of incoming analogue voltage from the peripheral
4. Fourth Row: UV Risk Level in accordance with the Australian BOM UV Index risk scale: http://www.bom.gov.au/uv/
5. Fifth Row: Date and elapsed time since commencement of Run
6. Sixth Row: Button A is Exit from app; time in secs until next logging event.

Using the app

IMPORTANT: the sensor requires a source of UV light to operate, and will not show a value unless exposed to direct sunlight or a UV light.

It is difficult to observe the screen in direct sunlight but the app is measuring and logging the UVI at the data logging interval set by the _config app. These values are stored in the Kookaberry’s memory in a CSV file called SenseUVI.csv, and transmitted by radio at the data logging interval. These values can be captured by running SenseRX on a Kookaberry not more than about 5 metres distant.

The sensor used in this app operates in the same way as the ambient light sensor except that instead of operating in the visible light frequency range of 380-700nm, its photodiode is sensitive to ultraviolet light in the frequency range 200-370nm.

The relationship between UV index and the photoelectric current generated by the photodiode is linear. The ultraviolet radiation falling on the photodiode generates a voltage between 0-1V which corresponds to a UV index between 0-11.

For this sensor, each point on the UV Index scale is equivalent to 20 milliwatts per square meter of UV radiation. This is the “Analog Value” in the table below.