Cisco Systems XR 12406 manual Troubleshooting an AC Power Subsystem, AC-Input Power Supply LEDs

Chapter 4 Troubleshooting the Installation

Troubleshooting an AC Power Subsystem

Troubleshooting an AC Power Subsystem

AC PEMs provide –48 VDC OUTPUT. The +5 VDC OUTPUT from the CSF powers the MBus module on each card in the system. The MBus module, in turn, control the DC-DC converters also present on each card in the system. The DC-DC converter takes –48 VDC from the power supply and converts it into +2.5, +3.3 and +5 VDC, which is distributed to the card circuitry.

AC PEMs are monitored by the MBus module and the RP for over- or undervoltage and over- or undercurrent conditions.

Begin checking the AC-input power subsystem by first looking at the LEDs on the AC-input power supplies. Figure 4-1 shows the location of the LEDs on the power supply.

Figure 4-1 AC-Input Power Supply LEDs

3

1

	57916
2	5

4

1

2

3

AC-input power supply

Handle

Power standby switch

4Captive screws on release levers

5LEDs

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	Cisco XR 12406 Router Installation Guide
4-6	OL-13831-01