HP SW TL881 DLT Mini-Lib/1 Compaq StorageWorks TL881/TL891 Family MiniLibrary - Page 84

Installation 3-3 Positioning the Modules The Expansion Unit must be mounted at the top of the stack, which places its control panel at a convenient height. The control panels of the Data Unit MiniLibrary Base Modules are of secondary importance, as they serve mainly to help localize system failures. When installed, the motor drive assembly of the PTM is directly behind the Expansion Unit. Data units and MiniLibrary Base Modules can be installed anywhere below the Expansion Unit, in any order. There might be a slight performance advantage in making the MiniLibrary Base Modules contiguous, but gaps are permitted. The size of a gap is limited by the fact that some number of 7 in (18 cm) must bridge each gap of PTM track sections. For safety, available cover plates should be installed on all PTM sections that are not connected to MiniLibrary System modules. The Expansion Unit senses the position of each module during initialization at power-up. Even if there are gaps between modules, the system will operate correctly. If you plan to leave gaps between modules, be sure to order additional PTM track segments and cover plates equal to the length of the gap. Mechanical Installation Assembly of the PTM requires experience working with moderately complex mechanisms, and the ability to follow directions carefully. Identifying the Parts of the PTM Locate and identify the PTM internal and external parts. The PTM is made up of the following external parts, shown in Figure 3-1 (see Table 3-1).