HP StorageWorks Scalable File Share for SFS20 Enclosure Hardware Installation Guide Version 2.2

2.6 Power Distribution System
AC power is distributed to the rack through three 24-amp (North America, Latin America, or
Japan) or 32-amp (international) 0/1U power distribution unit (PDU) assemblies.
The PDUs consist of two main parts: the control unit (Figure 2-19 “Power Distribution Unit”)
and the extension bars, more commonly called power strips (Figure 2-20 “Group of Three Power
Strips”). Each PDU has one control unit and four power strips. The control units are usually
referred to as the PDU.
Figure 2-19 Power Distribution Unit
Note:
Figure 2-19 “Power Distribution Unit” shows only PDUs 1 and 3. Each HP SFS rack has three
PDUs.
The three PDUs are mounted horizontally (1U position) at the bottom of each rack. PDUs 1 and
2 are mounted at the 1U position with PDU1 in the front of the rack and PDU2 at the rear of the
rack. PDU3 is mounted at the 2U position in front of the rack above PDU1. On the DL360 1:1 and
2:1 expansion cabinets, the PDUs mount on both sides of the rack rather than at the bottom.
The control unit is a single-phase unit that branches out into four single-phase branch circuits.
The power strips plug into the control units. The control unit has four outlet receptacles. However,
all four outlet receptacles might not be in use simultaneously because the total capacity of each
PDU cannot exceed 24 amps for models shipped to the US and Japan or 32 amps for international
models.
The control unit houses the main power switch, circuit breakers, load groups, and power-on
light. The control unit features include the following:
• Over-current and short-current protection for each branch circuit (four 15A UL-489 Listed
circuit breakers)
• Easy identification of overloaded circuits (full-trip circuit breakers move to the OFF position),
thereby minimizing down time resulting from overload conditions
• Manual on/off control for each of the four output load groups
• Main AC input power on/off switch and pilot indicator
• Switch guards to prevent inadvertent power off
• Secure outlet power cable retention
Each power strip has eight outlet receptacles. Three power strips are mounted together. Each
power strip in a group of three power strips are connected to the same numbered PDU circuit
breaker. For example, the three power strips in one group are connected to circuit breaker 1 on
each of the PDUs. The groups of three power strips are mounted at the lower left rear (powered
from PDU breakers 1 and 2) and lower right rear (powered from PDU breakers 3 and 4) of each
cabinet.
62 HP StorageWorks Scalable File Share Components