Siemens Building Technologies, Inc.has developed two new CD tools to help customers understand VFD technology and provide a simple method of calculating harmonic voltage and current distortion when using VFDs in building applications. The VFD "A to Z"™ CD-ROM is an educational tool that explains Siemens SED2 VFD capabilities. It includes multimedia presentations and technical training videos on the SED2 family of products, conventional and e-bypass options, harmonics basics, and a documentation library.