Dial Shelf Field-Replaceable Units
Cisco AS5800 Universal Access Server Hardware Installation Guide1-30
Figure1-17 CiscoAS5800 Enhanced AC-Input Power Shelf—Rear View
For detailed specification tables, refer to AppendixA, “Cisco AS5800 Specifications.”

Power Supply Safety Features (Enhanced AC-Input Power Shelf)

The power supplies in the enhanced AC-input power shelf have the following safety features:
•AC power supplies installed in the enhanced AC-input power shelf are protected against
overcurrent by circuit breakers, and against overtempe rature by internal protection circuits.
•A metal spring-clip locking mechanism in the ejector lev er s holds indi vi dual A C po wer supp lie s
in place and prevents the power supply from vibrating or sliding out of the power bay and
dislodging from the power backplane.
•Double grounding lugs (as per NEBS requirements) on both the enhanced A C-inpu t po wer s helf
and the dial shelf provide electrical grounding.
•A metal safety cover slides into grooves on the rear underside of the dial shelf to shield the DC
power cables from possible short circuit and to protect from electrical shock.
•The power supplies are self-monitoring. Each power supply monitors its own temperature and
internal voltages. An internal fan in each power supply draws cooling air from the front of the
power shelf, through the power supply, and out the rear of the power shelf. The power supply
airflow is separate from that of the rest of the CiscoAS5800 Universal Access Server
components.
Internal monitoring data is passed to the dial shelf through the maintenance bus (MBus)
monitoring system. You can view this data through a terminal connected to the router shelf
console port. The command to display the monitoring information is described in the Cisco
AS5800 Universal Access Server Software Installation and Configuration Guide
(DOC-AS5800-SICG=). The Cisco AS5800 Universal Access Server Software Installation and
Configuration Guide will be replaced by the Cisco AS5800 Universal Access Server Operation,
Administration, Maintenance, and Provisi oning Guide, available later this year.
24518
AC-input power
receptacles
Ground post
(chassis ground
does not connect to
+/- studs)
BUS +
terminal
stud
(-48 volt return)
BUS -
terminal
stud
(-48 volt input)