Power Conditioner - Usages

Usages

Power conditioners can vary greatly in specific functionality and size, with both parameters generally determined by the application. Some power conditioners provide only minimal voltage regulation while others provide protection from half a dozen or more power quality problems. Units may be small enough to mount on a printed circuit board or large enough to protect an entire factory. Small power conditioners are rated in volt-amperes (V·A) while larger units are rated in kilovolt-amperes (kV·A).

Ideally electric power would be supplied as a sine wave with the amplitude and frequency given by national standards (in the case of mains) or system specifications(in the case of a power feed not directly attached to the mains) with an impedance of zero ohms at all frequencies.

No real life power feed will ever meet this ideal. Deviations may include:

• Variations in the peak or RMS voltage are both important to different types of equipment.
• When the RMS voltage exceeds the nominal voltage by 10 to 80% for 0.5 cycle to 1 minute, the event is called a "swell".
• A "dip" (in British English) or a "sag" (in American English – the two terms are equivalent) is the opposite situation: the RMS voltage is below the nominal voltage by 10 to 90% for 0.5 cycle to 1 minute.
• Random or repetitive variations in the RMS voltage between 90 and 110% of nominal can produce a phenomenon known as "flicker" in lighting equipment. Flicker is the impression of unsteadiness of visual sensation induced by a light stimulus on the human eye. A precise definition of such a voltage fluctuations that produce flicker have been subject to ongoing debate in more than one scientific community for many years.
• Abrupt, very brief increases in voltage, called "spikes", "impulses", or "surges", generally caused by large inductive loads being turned off, or more severely by lightning.
• "Undervoltage" occurs when the nominal voltage drops below 90% for more than 1 minute. The term "brownout" in common usage has no formal definition but is commonly used to describe a reduction in system voltage by the utility or system operator to decrease demand or to increase system operating margins.
• "Overvoltage" occurs when the nominal voltage rises above 110% for more than 1 minute.
• Variations in the frequency
• Variations in the wave shape – usually described as harmonics
• Nonzero low-frequency impedance (when a load draws more power, the voltage drops)
• Nonzero high-frequency impedance (when a load demands a large amount of current, then stops demanding it suddenly, there will be a dip or spike in the voltage due to the inductances in the power supply line)