Harmonic measurements using a digital storage oscilloscope

It is pointed out that the availability of high-quality digital oscilloscopes at reasonable cost, which can be connected to the power system using current transformers and potential transformers to capture and digitize voltage and current waveforms, allow the plant engineer to make fast, accurate harmonic measurements on the plant power system. Microprocessors, often built into the oscilloscope, can quickly and easily analyze this digitized data. The need for harmonic field measurements, for equipment required, and the properties of the fast Fourier transform (FFT) algorithm are discussed. >