3-phase Wye
3-phase Delta

Hyperscaler Data Centers and the Importance of Three-Phase PDUs

Today's data centers are experiencing increasing demand for energy consumption, driven by servers that are constantly undergoing consolidation and virtualization.

This trend that started a few years ago and is here to stay. The main contributors to this trend are the Internet of things (IoT), the cloud and new 5G systems, which are pushing energy demands even further than previously imagined. The result is a
increased demand for computing and storage capabilities.

Energy consumption per rack has almost tripled in recent years. A few years ago, it was possible to install 10 high-power servers in an IT rack and achieve a maximum power load of 6

Today, new IT limits see more blade servers or many more 1RU servers in the same rack, consuming up to 20 kW per rack.

Single-phase systems distribute current through two wires: a live (active) wire and a neutral wire. The alternating current sine wave crosses the zero point at regular intervals. These
Single-phase systems are frequently installed in residential environments that require a small
energy consumption.

Three-phase systems consist of three sine waves, each positioned at 120 degrees. Each
one (phase) carries a separate wire. Due to the relationship between phases, the current and voltage never drop to
zero. This allows three-phase systems to provide much more power than a system

Phase balancing, by connecting loads across all three phases in the PDUs, helps minimize
harmonic currents and the need for large neutral cables. This allows optimal use of
upstream electrical infrastructure capacity, resulting in greater overall efficiency of the
data center and helps minimize costs.
The comparison tables below show the dramatic difference in power capacity
between the single-phase and three-phase PDUs.

Phase configurationVoltage/CurrentPlug typeMax. power capacity (kW)
Three phase DELTA208V 60AIEC60309 3P+E 60A17.2
Three phase WYE346-415V 30AIEC60309 3P+N+E 30A16.6
Three phase DELTA208V 30ANEMA L15-30P Twistlock8.6
Three phase WYE100-120/200-240V 30ANEMA L21-30P Twistlock8.6
Three phase WYE200-240/346-415V 30A 3Phase WYENEMA L22-30P Twistlock16.6
Three phase WYE100-120/200-240V 20A 3 Phase WYENEMA L21-20P Twistlock5.7
Three phase WYE200-240/346-415V 20A 3NEMA L21-20P Twistlock11
single phase200-240V 30A 1 PhaseNEMA L6-30P Twistlock4.9
single phase200-240V 20A 1 PhaseNEMA L6-20P Twistlock3.3
single phase100-120V 30A 1 PhaseNEMA L5-30P Twistlock2.8
single phase100-120V 20A 1 PhaseNEMA L5-20P Twistlock1.9
Three phase WYE380 – 415V 32AIEC60309 3P+N +E 32A22.2
Three phase WYE380 – 415V 32AIEC60309 3P+N +E 16A11.1
single phase220-250V 32AIEC60309 1P+N +E 32A7.2
single phase220-250V 32AIEC60309 1P+N +E 16A3.6
Balanced loads across all three phases entering the data center help maintain the power factor of the incoming power and avoid any penalties imposed by utility companies. Even if current load requirements are not too high, bringing three-phase power to the rack provides the scalability required for the future. The data center of the future requires an agile, scalable and flexible infrastructure. Since power is what keeps critical equipment running, it is important to choose a PDU that meets these requirements.