Specifications

• Redundancy for both hardware failures and power input failures
• Hot-plug capability for any BPS in a redundant configuration
• Better data security, maintenance scheduling, and maintenance operations without system
interruption
Figure 17. Power inputs and interconnects in the HP 9000 rp7440 Server are designed for fault-tolerant power compliance.
Fault-tolerant power compliance in the HP 9000 rp8440 Server
The AC input to the HP 9000 rp8440 Server is divided into four separate circuits. Each circuit is fed
by any 50- to 60-Hz high line source through four line cords (“high line” refers to 200 to 240 V
operation). A minimum of two power cords is used to maintain normal operation of the HP 9000
rp8440 Server. A second set of two cords is added to improve system availability by protecting, for
example, against power grid failures or accidentally tripped circuit breakers. Four power cords are
used to enable redundancy and hot-swap functionality of the bulk power supplies. This power is
routed from four individual 20-A circuit breakers through input line filters to six internal bulk power
supplies. These four lines are labeled A0, B0, A1, and B1 at the line filter inputs on the back panel of
the HP 9000 rp8440 Server.
Figure 18 shows the HP 9000 rp8440 Server power configuration. Each AC inlet feeds three HP
9000 rp8440 Server BPSs, and two separate AC inlets feed each bulk supply. The design of the
individual BPSs and the configuration of the interconnect meet all the conditions for fault-tolerant
power compliance.
Each BPS shown in Figure 18 can be thought of as two sub-power supplies housed in a single BPS
module. If only Grid A power cords are used, only one of the two sub-power supplies is in use. The
other supply is off until the Grid B cords are used. The benefit of this design is that when utilizing all
four power cords, the HP 9000 rp8440 Server has 2N+1 redundant power protection.
The dual AC modular power supplies provide:
• The ability to purchase only the amount of power conversion necessary for the intended HP 9000
rp8440 Server configuration
• Redundancy for both hardware failures and power input failures
• Hot-plug capability for any BPS in a redundant configuration
• Better data security, maintenance scheduling, and maintenance operations without system
interruption
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