Introduction1-4Power Distribution SystemThe SmartSwitch 9000 uses a distributed DC power distribution system(Figure 1-2) similar to those used in super computers. Three separate power busesare used to distribute DC power. The 48-volt DC System Power Bus, located onthe backplane, powers all modules and the system cooling fans. The DiagnosticPower Bus provides 5 volts DC to all of the system’s diagnostic controllers andthe Environmental Module. The INB Termination Power Bus provides 3.3 voltsDC to the SmartSwitch 9000 INB termination modules (ITM).To offer the greatest variety of power options, the 48-volt DC System Power Busand all components that use this bus are capable of operating using voltageranging from 40–60 volts DC. This capability allows the SmartSwitch 9000 tooperate from typical AC power and to charge batteries in a battery backup unit oroperate on DC power, such as found in a central office or a battery backup system.Figure 1-2. Distributed DC Power Distribution SystemRelated ManualsThe manuals listed below should be used to supplement the procedures andtechnical data contained in this manual.SmartSwitch 9000 Installation GuideSmartSwitch 9000 9C300-1 Environmental Module User’s GuideIn addition, each Interface Module has a user’s guide.207 - 264 voltsAC Power Supply56 volts 5 volts 3.3 volts INBAC Power Supply56 volts 5 volts 3.3 volts INBDC/DCConvertorDiagnosticControllerCommunicationsSystems ComponentsDC/DCConvertorDiagnosticControllerCommunicationsSystems Components48 Volt System Power Bus5 Volt Diagnostic Power Bus207 - 264 volts3.3 Volt INB Termination Power Bus