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Power Fundamentals

Step-down transformer

A step-down transformer reduces voltage from a higher utility or distribution level to a lower facility voltage. Data center projects may use multiple transformation stages from transmission or sub-transmission down to medium-voltage and low-voltage distribution.

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Liquid cooling

Liquid cooling removes heat using liquid closer to the IT components than traditional room air cooling. It is increasingly important for AI workloads because rack power densities can exceed practical air-cooling limits.

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Single-phase power

Single-phase power is AC power delivered through one alternating voltage waveform. It is common for smaller loads and support equipment, but large data center service is normally planned around three-phase systems.

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Bulk electric system

Bulk electric system generally refers to transmission elements and connected real/reactive power resources at defined voltage and configuration thresholds, excluding local distribution. Whether an asset is BES-relevant can affect reliability standards, studies, and operating requirements.

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