COVID-19: Critical business support and our focus on employee health. Learn More

The Raritan Blog

Flexible 400V Power Distribution

Posted on August 30, 2010 by Greg More

Today’s high power demands, increasing power costs and constantly changing equipment require data center and facilities managers to look for power solutions that can deliver a lot of power but are flexible. A typical data center has both medium density (5-10 kW/rack) and high density (15-30 kW/rack) equipment racks. For example, some racks may have 2U/4U application and database servers, others may have 1U Web servers, still others may support blade servers, storage networks, or high density networking fabric.

The power requirements for this variety of equipment can range from single phase to three phase, rack power (kW) may be anywhere from 5 kW to 30 kW per rack, and there could be dozens of different physical receptacles. The key is to efficiently utilize the available power capacity and to maintain uptime to the greatest extent possible while changes are made.The traditional approach uses pedestals at several locations in the data center with under-floor conduit or whips from the pedestal to racks. All the cable under that raised floor can impede air flow and cooling. The fixed feeds lead to decreased flexibility and challenging serviceability. In fact, it is not uncommon for some cables to be abandoned in place.

 

Another approach worth considering is 400V three-phase power provided by overhead track busways with plug in modules which in turn feed intelligent rack PDUs. This deployment frees up more useable floor space than the pedestal approach. It also reduces the cable clutter under the raised floor for better air flow and cooling.

Both single and three-phase loads can be supplied from one busway so varying power densities can be fed with the same infrastructure. Some systems allow data center staff to add and remove circuits without de-energizing loads. This makes it easy to change voltage, current, and receptacle configurations as needs change. Power connections can be added and changed when needed which defers costs.

Running 400V from the busway directly to 400V rack PDUs eliminates transmission losses (480V–208V / 120V (4% loss) vs. 400V (0%)). Processors at 120V have 18% loss vs. processors at 230V (Line - Neutral at the PDU) which have a 15% loss. This deployment provides a net improvement of 7% (4% + (18%-15%)).

The rack PDU provides branch circuit overload protection at the rack and addresses the practical physical limitations to delivering multiple circuits such as for blade servers with multiple power supplies.

If an intelligent rack PDU (iPDU) is used, sophisticated energy metering, monitoring and management as well as environmental monitoring can be easily installed. This allows data center managers to monitor temperature and follow the latest ASHRAE guidelines to lower cooling costs.  The power metering allows managers to determine actual power requirements so they can do informed capacity planning. Armed with information from iPDUs and the flexibility of busway power, changes can be made as needs and layouts change. This means efficient use of available power including freeing up “stranded” power. The environmental monitoring ensures changes don’t lead to undetected hot spots.

For more detailed information about flexible 400V power distribution join Raritan September 30, 2010 at the Datacentre Dynamics show in Chicago.

Other Blog Posts

The New Dominion LX II: Why You Should Trade Up
Posted on April 2, 2020
Coronavirus Remote Management Checklist
Posted on March 18, 2020
The New Dominion LX II: Java-Free KVM-Over-IP for SMBs
Posted on February 5, 2020
Dominion KX IV-101 Newest Firmware Update
Posted on December 17, 2019
Rack PDUs Outlet Density and Types
Posted on November 14, 2019

View all Blog Posts

Subscribe


Upcoming Events

2020 DoDII Worldwide
August 2–5  •  Phoenix, AZ
AFCOM Data Center World 2020
August 24–27  •  San Antonio, TX
DCD NY 2020
September 1–2  •  New York City, NY
Critical Facilities Connect 2020
September 14–15  •  Charlotte, NC
Spiceworld 2020
September 15–20

View all Events

Latest Raritan News

Raritan Introduces Economical New Generation KVM-Over-IP Switch and Serial Access for SMBs
Posted on March 2, 2020
Extended IT rack power mapping possibilities with Raritan’s locking solution
Posted on October 23, 2019
Raritan Ranked as the Global Leader in KVM-over-IP Switches
Posted on October 21, 2019
Raritan’s New KVM-over-IP User Station Brings 4K Performance and Productivity to Remote Equipment Access
Posted on September 18, 2019
Raritan’s New 4K Ultra HD KVM-over-IP Switch Wins Best of Show Award at NAB
Posted on May 21, 2019

View all news