Considerations for a Highly Available Intelligent Rack Power Distribution Unit A White Paper on Availability
Introduction Data centers are currently undergoing a period of great change.
Reliability Intelligent rack PDUs (Figure 1), offering flexible and comprehensive remote management and real-time monitoring capabilities, can provide the best view of IT power consumption and rack operating conditions. However, while these new rack PDUs offer advanced capabilities, they are not much use if their core function is compromised or impeded: providing basic power distribution in any circumstance.
Below are key features that help keep the idle power consumption of intelligent rack PDUs low. • Aluminum construction - Aluminum has better conductivity than steel and helps keep the internal temperature rise to a minimum. It also makes the rack PDU lighter in weight, resulting in easier deployments. • Backlit LCD display • Bistable relays - These relays, also known as latching relays, draw power only when there is a change of state outside of normal operation.
Power Cord and Outlet Locking Software Electronic OCP Power cord and outlet locking mechanisms secure the physical connection and ensure the power cords are not accidently pulled out of the outlet, causing an inadvertent load drop. (Figure 3) Globally, the most common standard for outlets used in rack PDUs is IEC320 C13 and C19. IEC receptacles are internationally acceptable and handle output voltages up to 250V.
Switching Switching within rack PDUs is vital to being able to remotely turn on or off the connected equipment, and is enabled by the use of relays at each outlet. The relays used within rack PDUs can be one of three types: normally-open; normally-closed or bistable relays. • Normally-open relays require power to be supplied to them in order for the outlets to be able to deliver power to the connected loads.
11.29 12 10.16 10 8 5.88 6 4 2 0 2.04 Extrapolated value (incidents) for FY 2013 Extrapolated value (incidents) for FY 2010 6.84 2.48 Total DC shutdown Localized shutdown Limited Outages Figure 5. Frequency of data center outages over two years, based on results of 2013 survey from the Ponemon Institute. There are three factors that need to be considered for better maintainability. This also holds true at the rack level.
Conclusion Emerson Network Power-Global Headquarters 1050 Dearborn Drive P.O. Box 29186 Columbus, Ohio 43229 Tel: +1 614 888 0246 With increasing data center densities, a single rack can now support the same computing capacity that used to require an entire room.
