Two CDs have been released to help the user with understanding variable-frequency drive (VFD) technology and to provide a simple method of calculating harmonic voltage and current distortion when using VFDs in building applications. The VFD "A to Zâ„¢" CD-ROM is an educational tool that explains the company's SED2â„¢ 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. The "SED2 Harmoneeâ„¢ Harmonics Calculator Tool" CD is a harmonics analysis tool that provides data on the full harmonic spectrum and harmonic order values. It compares expected results with worldwide harmonics standards, including IEEE519-1992, and gives the user the ability to compare harmonics generated by other comparable six-pulse drives versus the SED2 VFD product family. It also compares conventional drives with and without the use of filtering devices to reduce harmonics such as line reactors. These tools are available on the manufacturer's Web site.

Siemens Building Technologies Inc., 1000 Deerfield Pkwy., Buffalo Grove, IL 60089; 847-215-1000; www.sbt.siemens.com/hvp/components/products/variablefrequencydrives/default.asp

eProduct #195