WAYNE E GRASSEL
Engineers in Bethel Park, PA
License number
Pennsylvania PE041265E
Category
Engineers
Type
Professional Engineer
Address
Address
Bethel Park, PA 15102
Professional information
Hand-Held Power System Harmonic Distortion Meter With Selective Activation Of Display
US Patent:
4964055, Oct 16, 1990
Filed:
Nov 25, 1987
Appl. No.:
7/125548
Inventors:
Wayne E. Grassel - Bethel Park PA
Mark F. McGranaghan - McDonald PA
Mark F. McGranaghan - McDonald PA
Assignee:
Cooper Industries, Inc. - Houston TX
International Classification:
G01R 2316
US Classification:
364485
Abstract:
A hand-held, battery-powered harmonic distortion meter reduces the level of the AC power waveform of interest to a level compatible with the measurements to be performed, converts successive portions of the reduced waveform to digital representations in a multi-bit format for processing, stores a predetermined number of sequences of the digital representations, processes the stored sequences according to a fast Fourier transform algorithm using time decomposition with input bit reversal to produce intermediate calculations of the real and imaginary parts of the DC, fundamental frequency and harmonic components of the input waveform, further processes the intermediate calculations to obtain various parameters of the input waveform including magnitude of the harmonic components as a percentage of the fundamental frequency of the waveform, and selectively displays the final calculations according to switch selections on the face of the meter.