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Why we use UPS instead of Power Invertors


Why we use UPS instead of Power Invertors in Computing
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The primary role of any UPS is to provide short-term power when the input power source fails. However, most UPS units are also capable in varying degrees of correcting common utility power problems:

Power failure: defined as a total loss of input voltage.

Surge: defined as a momentary or sustained increase in the main voltage
.
Sag: defined as a momentary or sustained reduction in input voltage.
Spikes, defined as a brief high voltage excursion.
Noise, defined as a high frequency transient or oscillation, usually injected into the line by nearby equipment.

Frequency instability: defined as temporary changes in the mains frequency.

Harmonic distortion: defined as a departure from the ideal sinusoidal waveform expected on the line.

UPS units are divided into categories based on which of the above problems they address[dubious – discuss], and some manufacturers categorize their products in accordance with the number of power-related problems they address.
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