Selecting the Right Power Meter

The set of electrical properties that allows electrical systems to function in their intended manner without significant loss of performance or life is called Power Quality. Power quality analysis is an opportunity to be aware of the quality of electric power and study the changes in RMS voltages, transient voltages, wave shape, voltage imbalance, flickers, etc.

Power quality analysis involves several issues like classification and characterization of electrical disturbances, propagation of disturbances and measurement campaigns. Wave-shapes are used for evaluation of harmonic distortion and voltage profiles for steady-state RMS variations. Power quality monitoring also includes the detection of electrical disturbances such as sags, harmonics, swells, etc. Once the disturbance has been detected and recorded, analysis of the captured waveforms can give more information about the disturbance.

A power meter helps in analysis of motor start-up, detection of unbalanced situations that lead to equipment failures, verification of power distribution systems and measurement and recording of the parameters of power quality. It helps to avoid power disturbance. Power meters include both single-phase and three-phase power quality analyzers for predictive maintenance, quality of service compliance testing and load studies.

With so many options in the market, choosing the correct power meter can be a difficult task. The primary step in choosing a meter is to determine the goal for the monitoring system. There are easier-to-use, less sophisticated and cheaper meters which measure parameters such as energy usage, peak demand, and basic voltage/current. For more complex requirements in industrial facilities, more capable power meters are available as well. Usually, a meter's cost determines its limitations because all metering devices are constrained by hardware, firmware, and software functionality.

Power meters should include basic features like the ability to capture, view, and provide alarms based on anomalies or steady-state conditions that can affect the operation of equipment or processes. A good meter must also be able to examine several categories of power quality issues. In facilities which require higher levels of power quality, a power meter which provides comprehensive information on all power quality categories will be more useful, but such a meter will also be more expensive.

The real potential of a good power quality monitoring system also lies in its extensive link between the hardware and software. A permanently mounted metering scheme has additional strengths because it's typically layered through the electrical system. If the software has access to data from all power meters, characterization of the power quality throughout the facility is easier.