Power Quality Testing

Electrical Power Quality.

Power quality is a measure of the purity of electrical energy delivered to equipment. The term “power quality” can imply service reliability in terms of limiting permanent or momentary outages. It can also mean maintaining acceptable voltage or addressing issues of harmonics affecting sensitive equipment.

Power quality is important to anyone who relies on equipment and systems that are sensitive to electrical disturbances. The impact of power quality disturbances can be substantial. Even the smallest variation can have significant implications in the form of lost time, productivity and equipment replacement costs.

Power disturbances can have their source in either the electric utility service provider or in the customers wiring system or equipment. These disturbances can be classified into categories that can vary in effect, duration and intensity. Some types of equipment can be sensitive to the resulting voltage changes.

Power Quality Investigation.

A Power Quality Investigation is generally performed to determine if there is too much distortion of the voltage applied to equipment and diagnose the cause. Electrical current is also monitored to assist in determining the cause of distortions. Voltage distortion tolerance curves have been developed by the Computer Business Equipment Manufacturer’s Association (CBEMA) that provide a guideline within which most computer equipment will operate without trouble. Other equipment tolerances, as specified by manufacturers, are also considered.

The most common reason for a load measurement survey is to assist in diagnosing a Power Quality problem. Other common reasons include:

Confirmation of loading or overloading.
Comparison of pre-construction to post-construction equipment efficiency.
Measuring the effect of starting and/or running significant equipment.