Chapter 9 Connecting the cables to the BCM50 system 113Installation and Maintenance GuideTo connect extensions to DSM16, DSM32, ASM8, 4x16, G4x16, orG8x16 MBMs1 Read the warnings in the Wiring warnings on page 109 section.2 Obtain a 25-pair cable with an RJ-21 connector on one end.3 Plug the RJ-21 connector of the cable into the RJ-21 connector on the front of the MBM.Use the upper RJ-21 connector on the G4x16/G8x16 MBMs to connect digital extensions.4 Select the appropriate option to secure the RJ-21 connector to the MBM:• If you use a straight RJ-21 connector, use the two supplied screws on the sides of theconnector to secure it.• If you use a right-angle RJ-21 connector, use the supplied screw on the left side of theconnector to secure the left side of the connector. To secure the right side of the connector,use the supplied cable tie to fasten the 25-pair cable to the anchor on the MBM.5 Connect the other end of the cable to the local connecting blocks.6 If you connect extensions to a DSM32, repeat steps 2 to 5 for the second RJ-21 connector.7 Select the appropriate option for your system:• If your BCM50 system has another expansion unit, repeat this procedure if you add moreextensions, or proceed to Connecting telephone lines to the expansion units on page 111 ifyou add telephone lines.• If your BCM50 system has no other expansion unit, proceed to Connecting the auxiliaryequipment on page 113.For information about wiring the station MBMs:• 4x16 wiring charts on page 271• G4x16 and G8x16 wiring charts on page 275• DSM16 and DSM32 wiring charts on page 279• ASM8, ASM8+, and GASM wiring chart on page 283Connecting the auxiliary equipmentThe main unit has connections for an auxiliary ringer, an external paging system, and a musicsource.You can connect this auxiliary equipment through the auxiliary terminal block on the wiring fieldcard (WFC) or the patch panel. See the procedure To connect the cables to the wiring field card(optional) on page 117 or the procedure To connect the cables to the patch panel (optional) on page117.For information about connecting auxiliary equipment:• Connecting an auxiliary ringer on page 114• Connecting an external paging system on page 114• Connecting an external music source on page 115
