42 Chapter 2 Introducing the BCM50 hardwareNN40020-302BCM50 Expansion unit and media bay modulesIn addition to a main unit, the BCM50 system can have up to two BCM50 expansion units. Anexpansion unit connects to the main unit and provides additional functionality. For expansion unitport locations and descriptions, see the figure BCM50 expansion unit connections on page 42 andthe table BCM50 expansion unit ports, connectors, and descriptions on page 42.The BCM50 expansion unit accommodates one media bay module (MBM) that connectsadditional telephony equipment to the BCM50 system. The MBMs connect with external devicesto implement various types of voice trunks and stations. For a list of trunk and station MBMs thatcan be used with your BCM50 system, see the table Trunk MBMs on page 45 and the table StationMBMs on page 47. For a complete list of MBMs with links to additional information, see also thetable Media bay modules on page 59.Ensure that the MBM dip switches are set correctly (see Verifying the media bay module switchsettings on page 96).Figure 7 BCM50 expansion unit connectionsWarning: External equipment connected to the auxiliary ringer, page relay, pageoutput, and music-on-hold interfaces must use safety extra low voltage (SELV).All four interfaces are SELV, and the external equipment connected to theseinterfaces must be SELV. If these interfaces are not SELV, you must use externalline isolation units (LIU).Table 2 BCM50 expansion unit ports, connectors, and descriptions (Sheet 1 of 2)Port/connector DescriptionLAN port (port 1) An RJ-45 jack used to connect the customer LAN to the main unit.The LAN port on the expansion unit connects to the internal Ethernet switch on themain unit. You can use the expansion unit LAN port to connect an additional device tothe LAN.Power connector A barrel connector jack used to connect the power supply to the expansion unit.Ejector ExpansionportPowerLAN portMBM bayRetention clipmounting hole
