John Yoon, PE, LEED AP, McGuire Engineers Inc., Chicago
Engineers must understand how the components in the HVAC systems they design use power and how they can be optimized without compromising traditional design values. Motors and drives are shown in relation to the design of HVAC systems.
A variable frequency drive (VFD) often is specified to reduce operational cost for pumps, fans, compressors, or any similar equipment with variable load profiles that may be found in a typical building. Here’s how to specify a VFD to meet load conditions while achieving efficiency.
Ten common issues that can affect functionality of motors and variable frequency drive (VFD) specification.
These guidelines dispel the confusion about matching variable frequency drives (VFD) and motors to fans and pumps that are typically encountered in commercial building applications. While the motivation to increase energy efficiency could be financial (reduced energy costs) or ethical (reduce greenhouse gas emissions associated with power production), it is taken for granted that VFDs are an easy way to improve energy efficiency in a motor application. And with these noble intentions in mind, the engineer will specify a VFD for his client. Oftentimes, that isn't the end of the story for the engineer.