IBM 73Y9591 server / storage / networking hardware Server Hardware / Parts

The IBM 73Y9591 is a bulk power controller assembly, designated BPC. In IBM System z and large Power frames the power subsystem is managed rather than passive: the BPC watches the bulk power regulators and distribution assemblies, controls the order in which the frame powers up, and reports faults through the service processor to the hardware management console. Controllers are matched to the frame generation.

IBM builds its large frame systems, the System z mainframes and the high end Power servers that share their packaging, around a bulk power subsystem rather than around individual power supplies. Mains comes in at the bulk power enclosure, is regulated and controlled there, and is distributed through the frame to converter assemblies at each book and drawer. Blowers, motor drive assemblies and, on the liquid cooled models, refrigeration or water cooling units hold the processor complex in its thermal envelope. Every one of those is a field replaceable unit.

Tech-Star is UK-based and supplies IBM frame power parts worldwide.