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Familiar with 277 volt? It may just be the power your data center needs.


Guest blog written by David Chetham-Strode, HP Product Manager - Enterprise Infrastructure Solutions


One of the basic laws of electricity is that higher voltages can carry more power.


Aside from the useable voltages typically seen in IT, another option exists for data centers. That option is the three-phase 480V and single-phase 277V configuration (480V/277V). This voltage provides for a staggering increase in available power.  In a modern 480V data center, the 480V is pulled through a transformer-less UPS direct to the HP 480V/277V Rackmount PDU in the rack. The HP 480V/277V Rackmount PDU is able to convert the 480V/3-phase to a 277V/single-phase circuit. This not only increases the amount of power efficiency by as much as 10 percent but also brings more than two times the power to the rack for those switching form a 120V single-phase setup to the 277V single-phase. For those looking for the big prize, switching from single phase to three-phase, the increase is a whopping 6+ times!




IT Equipment Autosenses 100-240V Only. Yes, But…


The power supplies in most servers and IT equipment have an auto-sensing feature that allows each device to automatically adjust to voltage levels ranging from 100V-240V. The question arises: What about equipment being able to sense 277V? The fact is that most IT equipment is not designed to run above 240V and cannot autosense 277V. To take advantage of the 277V power pipeline requires special connectors, power cables, and power supplies . The bottom line is that the 277V is a completely different standard.




Good News


There is good news in that the 480V/277V configuration only requires a minimal, upfront investment for what will eventually be a sizeable efficiency gain. The 277V setup does not need a huge building transformer, which inevitably leads to power losses in the conversion process. Nor does it require additional operational or capital investments. Efficiencies are gained since typical transformers would waste a significant amount stepping down the power from 480 volts to the more common 208 volts. Anywhere from 4-8 percent power efficiency may be lost during the traditional transformation of power to the IT equipment rack level. The introduction of the HP 480V/277V PDU circumvents these issues.


The HP 480V/277V Rackmount PDU performs the conversion to single phase at the rack itself, thereby ensuring a minimum loss of power. Overall, the HP solution helps save upfront investment costs and future energy expenses.




The HP 277V Portfolio


For datacenters looking to gain the greatest power efficiency via a 480V/277V setup, HP has a complete portfolio of rack power solutions to make the migration to 277V simple. The total solution at the rack eliminates the need for large, inefficient building power transformers in the data center to improve efficiency. The HP products available include:


HP 480V/277 Volt Rackmount PDU

277 Volt Rackmount Transformer

1200 Watt Common Slot 277 VAC Hot Plug Power Supply




Piqued Your Interest?


Check out the following links to learn more.  Still need help?  Post a comment or send us a message and we'll be happy to assist!


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