85Installation and Maintenance GuideChapter 7Setting media bay module DIP switchesBefore you install a media bay module, assign switch settings for the media bay module. Thesesettings determine which line numbers (trunks) or DNs (extensions) the equipment connected tothe module will have access to. The DIP switches are located on the back or underside of themedia bay module.Start from the list of modules you chose in Chapter 4, “Selecting the media bay modules for yoursystem,” on page 59.After you determine which DS30 blocks you want to use, and how much DS30 bus capacity eachmodule requires, you determine the location of the modules on the DS30 array. From thatinformation, you choose switch settings for each module. These settings are then set on the moduleDIP switches.This chapter describes the latter process of positioning your modules in the DS30 hierarchy anddetermining and setting the DIP switch settings on the module.Rules for assigning DS30 bus blocks and offsetsMedia bay modules are assigned to DS30 bus blocks in a specific hierarchical manner. Thissection describes the preferred order of positioning for each type of module.Notes about assigning modulesThe following are some general notes about assigning modules:• If you chose a 3/5 DS30 split for your system, DS30 07 cannot be used by any module. Formodules that require two DS30 buses, this means that you cannot set the DIP switches to DS3006 for those modules, because the second level of lines would fall into 07, and would not beaccessible. Refer to Figure 37 on page 87.Refer to “Understanding DS30 bus blocks” on page 62 for more information about 2/6 and 3/5DS30 splits.• DSM 32 modules require two DS30 bus numbers. When you assign the first DS30 bus numberto a DSM 32, the module automatically adds the next DS30 bus. For example, if you assignDS30 02 to a DSM 32, it uses DS30 02 and 03. However, you cannot choose DS30 07 for theNote: Fiber Expansion Module (FEM) switchesThe switches on the fiber expansion module (FEM) do not work in the same way as thoseon the other media bay modules. On the FEM, the switches turn the fiber ports on and off.For information about setting the switches on an FEM, refer to “FEM switch settings” onpage 108.
