We’ve seen dramatic improvements in data center physical infrastructure equipment and practices in recent decades, driven in large part by a need for more power density, the sheer number of IT devices in the data center, and the need to add and remove IT devices quickly and easily, with no downtime.
Yet old ways die hard. Visit a new data center today and you may well see lots of traditional architecture, such as massive transformer-based PDUs feeding under-floor wired circuits via conduit. These methods can result in:
- Data center operators being unable to tell which branch circuits are near overload or which are candidates for eventual overload
- Under-floor cooling plenums blocked by a snake’s nest of cables, restricting the air flow necessary for the IT load
- Large transformer-based PDUs (power distribution units) running out of branch circuits or generating heat that must be cooled, increasing costs and decreasing data center efficiency
- Data center operators having to do “hot work” (make circuit changes on live wiring)
Data center technology and practices have evolved to the point where such historical power distribution architecture is – or should be – obsolete. Rather than continue to adhere to a traditional data center model that ill-serves the enterprise, data center owners should aspire to an optimal, or ideal power distribution system.
As described in an APC by Schneider Electric white paper, an ideal power distribution system would possess the following characteristics:
- No under-floor cables
- All power levels would be supported using a single cable to the IT enclosure
- All circuits would be monitored for power
- New circuits could be safely added to the live system
- Breaker status could be monitored remotely
- IT zones and associated power distribution could be deployed over time
- Every circuit could be managed for capacity and redundancy
- No unneeded copper installed
- It would be highly efficient
Numerous new products and technologies are available to help create an ideal power distribution system, including modular power distribution systems, branch circuit power metering, overhead cable trays with flexible power cords, overhead fixed busway with removable power taps, high-power, pluggable rack power distribution units, transformerless PDUs and power capacity management software.
How an ideal power distribution system is set up depends on the size of the data center. Larger data centers might distribute the main critical bus power from the UPS to IT rows using overhead busways. For smaller data centers (300 kW or less) with only one or two PDUs, an overhead busway may not be necessary.
Modern power distribution systems afford great flexibility. They allow IT racks or entire PDUs to be installed or changed with no new wiring, they distribute power overhead, they improve the data center’s electrical efficiency, they reduce consumption of copper, and they have a standard capacity management system.
These systems are necessary to meet the requirements of data center environments defined by rapid change, evolving needs and flexible power consumption.
For more information on data center power distribution, read the APC by Schneider Electric white paper, A Scalable, Reconfigurable, and Efficient Data Center Power Distribution Architecture.
