Sunshine Pyranometer

The Sunshine Pyranometer type SPN1 from Delta-T Services (UK) measures global (total) and diffuse radiation, and sunshine state – all in one instrument! It is easy to use and needs no routine adjustment or polar alignment. The SPN1 is a meteorological class instrument designed for long-term outdoor exposure, and is an affordable alternative to traditional shade-ring pyranometers, the Campbell-Stokes and other sunshine recorders. It also provides some of the functionality of expensive pyrheliometers.
Global (total) and diffuse horizontal irradiance in W.m-2 ; Sunshine threshold to WMO definition: >120 W.m-2 in the direct beam; No moving parts, no shade rings, no motorised tracking needed; No routine adjustment or polar alignment needed; Works at any latitude.
For Photovoltaic applications, the SPN1 is also proving popular for PV applications. For major PV investments, when it is important to identify the best sites, an SPN1 can be used to quantify the available global and diffuse radiation. After installation of the PV facility, the SPN1 can help monitor the short and long term efficiency of the panels and this data can be fed back into improved PV panel design.
The unique design of the Sunshine Pyranometer uses a patented array of thermopile sensors and a computer-generated shading pattern to measure the direct and diffuse components of incident solar radiation. The shading pattern and thermopiles are arranged so that at least one thermopile is always fully exposed to the solar beam, and at least one is fully shaded from it, regardless of the position of the sun in the sky. A microprocessor derives the global and diffuse radiation values, which allows an estimate of the direct beam, and hence sunshine hours, to be calculated.
The Sunshine Pyranometer is protected by patents EP 1012633 & US 6417500.The Sunshine Pyranometer provides 2 voltage outputs for global and diffuse energy, and a digital output of sunshine state for data logging. Delta-T`s low cost logging solution for the SPN1 is the GP1 Data Logger.
The SPN1 has a precision ground glass dome and uses wideband thermopile sensors; it achieves a near ideal spectral and cosine response. The internal heater keeps the Sunshine Pyranometer clear of dew, ice and snow down to –20°C, ensuring reliable readings in difficult climatic conditions.