Harmonics

In the past, most industrial facilities could assume that the power received from the electrical utility was generally a pure sinusoidal waveform (good harmonics) and was considered clean power. However, today more and more industrial plants are finding that they have the problem of “dirty power” or conditions where voltage/current variations of the pure waveform are transient and cause distortions in power quality. In industrial plants, most of the harmonic distortions are self-induced often because of increased usage of variable frequency drives, power supplies and other components that use solid-state switching. Because harmonic distortions can be caused by internal plant components as well as neighboring facilities, it is crucial to understand the harmonics within your facility.

Harmonic distortion disrupts plants. Results include blown fuses, reduced capacitor life, reduced motor life, inability to operate to full motor load, reduced transformer life, and lost downtime through overloads tripping and logic faults in machine controllers.

MachineSense will record and detect harmonic distortions by measuring true-rms value as well as the instantaneous peak value of the wave peak. With this information, you can identify and track ongoing distortions that are occurring throughout your facility and then the various identified problems can be addressed. The advantage of MachineSense is that it can record these issues over a prolonged period since harmonic issues are often repeatable, but may not occur during periods of measurement by short duration power meters. Previous generation electrical power loggers often had limited memory and scope—as well as not being intuitive in the display of information for non-electrical plant management personnel.