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Power Infrastructure

Uninterruptible Power Supply

UPS

Battery-backed power system that maintains continuous supply to critical loads during mains failure.

Unit: kVA / kW

Full Definition

An Uninterruptible Power Supply (UPS) provides emergency power when the main source fails. Modern data centre UPS systems use double-conversion (online) designs that continuously convert incoming AC to DC and back, isolating equipment from power quality problems. Systems are sized in kVA or kW and typically provide ride-through of several minutes — enough for diesel generators to start and stabilise. Modular UPS designs allow N+1 or 2N redundancy within a row or pod.

Also Known As

uninterruptible power supplybattery backup

Source Reference

IEC 62040-3 — UPS Performance Requirements

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