The Pacific Energy Center (PEC) has a tool lending library that contains tools for measuring lighting and solar radiation, HVAC parameters, energy usage and data-loggers in general.  Each device has a unique data file and corresponding software to translate that data file into usable form.  It can be a big headache to take data from numerous instruments and combine it into one data file for further analysis.  To tackle this problem, the PEC wrote the Universal Translator software program to combine and analyze data from all of the devices in their library.   The software is free and open source. http://www.pge.com/pec.