IBM 7133 Series Service Manual

Chapter 1. Reference Information| The 7133 Serial Storage Architecture (SSA) Disk Subsystems can be attached to reduced| instruction-set computer (RISC) systems. Models 010 and 020 1 are rack-mounted units| that can be installed in a standard Electrical Industries Association (EIA) 19-inch rack.| Models 500 and 600 2 are deskside units.The 7133 can contain up to 16 SSA disk drive modules (eight at the front and eight at theback).| The 7133 has fan-and-power-supply assemblies that provide all the power and cooling for| the 7133. Models 010 and 500 have two or three fan-and-power-supply assemblies,| subject to configuration requirements. Models 020 and 600 always have three| fan-and-power-supply assemblies.The disk drive modules are connected to each other in strings of four modules (two stringsat the front of the 7133, and two strings at the back). These strings can be connected toeach other, to strings in other 7133s, or to SSA adapters. The adapters can be inseparate using systems or in the same using system.The 7133 can be disconnected from its related SSA adapters while the using system isrunning. Also, most of the field-replaceable units (FRUs) of the 7133 can be removed andreplaced while the 7133 and the using system are running. For a list of those FRUs, see“Concurrent Maintenance” on page 3-1.The customer’s preinstallation planning information contains information about the systemand its configuration.Chapter 1. Reference Information 1-1