Delta Electronics SS1-UM-1.05 SunScan probe, Beam Fraction sensor, Data Collection Terminal

SunScan probe

The light sensitive “wand” of the probe is 1 metre long, containing 64 photodiodes equally spaced along its length. The probe handle contains batteries and electronics for converting the photodiode outputs into digital PAR readings, which get sent to your Data Collection Terminal via the RS232 link.

Beam Fraction sensor

The Beam Fraction sensor (BFS) also measures PAR light levels. It is used to monitor the light incident on the canopy at the same time as you are making measurements beneath it. The BFS incorporates two photodiodes, one of which can be shaded from the direct solar beam by the shade ring. This allows the direct and diffuse components of PAR to be separated, which is necessary for the computation of LAI.

Data Collection Terminal

To observe and store readings from the SunScan probe, you need the Data Collection Terminal (a Psion Workabout). The Workabout is a lightweight, robust field unit with a full alphabetic keyboard for the annotation of readings. It comes with a removable Flashcard which can be used for data storage and transfer.

You can use a portable PC as a data collection terminal instead, but it is less convenient for field work.

SunData software

In order for the SunScan probe to communicate with the Workabout or a PC, it needs software. We pre-install the Workabout's SunData software, and we provide the SunData PC software on a 3.5 inch diskette which you must load into your PC. The SunData PC software is a DOS program; it does not require Windows, but it can be run in a DOS window. Data files are created in an ASCII text format which you can import into spreadsheets or other applications for analysis on any PC.

Field accessories

The sturdy field Carrying Case is designed to accommodate all the components of the SunScan system. It has room for an optional tripod mount which is intended primarily for use with the BFS, but which can equally well be used with the SunScan probe. Space is also provided for extension cables that may be ordered with the BFS.

SunScan User Manual v 1.05 Introduction • 7