COMPONENT DESCRIPTIONS10-28 Edition One XC1000 ServiceThe switch trunk cables are connected to the main backplane through25-pair male amphenol connectors. Loop- or ground-start telephone linesthat connect to ATICs should be connected to the top row of amphenolconnectors on the main backplane.Two terminators are located at the lower corners of the main backplane.The serial bus runs between these terminators, between card-cage slots 1and 18. These terminators are removed to connect a second frame.The main backplane contains the telecom ground connection for signalingover the trunks to the switch. (Tie-line interfaces are used for ground-starttrunks, DID trunks, and E&M.) The telecom signal connectors are prewiredat the factory and do not need to be connected at installation time.Do not remove the main backplane shield unless systempower is off. Removing the shield with the power on ishazardous to personnel and equipment.Caution!The main backplane is covered with a shield. Openings are provided forcable connections between TICs and the CO. Do not remove the backplaneshield unless directed to by Octel Communications.10.6 MAIN DISTRIBUTION BOARDThe main distribution board is located below the main backplane. Thedistribution board provides connectors for external access to the system.These connectors are used for connecting data links, the system managerterminal, remote alarms, and the RDAC port to the XC1000. Refer tosection 3.8 for information about connecting the data links, systemmanager terminal, remote alarms, and RDAC port to the XC1000.Figure 10-16 shows the major internal connectors on the distributionboard.The CPU and monitor card are connected to the distribution board topermit external access to the system. The CPU connects to the distributionboard at J28 and J29. J28 connects to rows A and B of the CPU connec-tor on the main backplane using the CPU AB cable. J29 connects to rowsC and D using the CPU CD cable.The monitor card connects to the distribution board at J26 and J27. J26connects to the monitor card’s A and B rows on the main backplane usingthe monitor AB cable. J27 connects to the main backplane using themonitor CD cable.The system and message-file cards are not connected to the distributionboard. The file cards communicate with the CPU through the mainbackplane.SECTION 10.5 – 10.6
