Virtual instruments are defined by the user while traditional instruments have fixed, vendor-defined functionality. A traditional instrument provides functionality with a finite list of fixed-functionality using the instrument front panel. With a virtual instrument, engineers and scientists can customize the acquisition, analysis, storage, sharing, and presentation functionality. Virtual instruments are much more flexible when changing measurement tasks. By not using vendor-defined, prepackaged software and hardware, engineers and scientists get maximum user-defined flexibility. The paper deals with virtual instrumentation approach to develop harmonic component analyzer according to international standard IEC 61000-4-7:2002/A1:2008. The paper presents the results of measurements performed on different loads.