Abstract: An apparatus for the analysis of power quality and the effects of harmonic distortions on machinery or equipment. The apparatus is compact, portable, and non-invasive in that the apparatus can be operatively connected to an electrical carrier without power interruption. A display device is built in allowing graphical display of averaged or continuously updated measurements and analysis. A central processing unit analyzes measurements using Fourier analysis.

Abstract: A monitoring apparatus for a tuned harmonic filter is provided to prevent electrical system and filter damage. A tuned harmonic filter is provided in an electrical system to prevent overheating, motor damage, flickering lights, capacitor failure, etc. The present invention provides a sensing device in conjunction with the filter reactor to provide a signal indicative of the true operating condition of the filter. A monitoring circuit compares the signal with normal operating conditions of the filter to determine if a "fault" is occurring. Timing devices provide for a delay or rapid disconnection of the filter and/or electrical system. Indicator devices are provided to aid in diagnostic analysis of an electrical system. A remote indicator device may be included.