Cisco AS5800 Product Overview 1-41
DC-Input Power Specifications
The PEMs provide –48 VDC power, which is distributed from the filter module to the dial shelf
backplane. The analog isolators in the filter module are provid ed with 15 VDC. No damage will
come to the PEMs if any or all outputs have no load (no load occurs when there are no cards plugged
into the backplane) or if the maximum i nput voltage is exceeded ; however, input voltages tha t exceed
75V will eventually trip the PEM 60A circuit breaker, a nd you ma y have to reset the breaker.
The Cisco AS5800 supports several types of logic cards with varying power requirements. As a
result, each logic ca rd DC-to-DC converter syst em is isolated from th e distributed –48 VDC power,
creating a more stable distributed power system.
AC-Input Power SpecificationsThe Cisco AS5800 accepts AC-input power using a separa te, self-contained AC-input power shelf,
which converts AC-input powe r i nto DC ou tput fo r use by t he DC-po were d dial she lf. T he AC-input
power shelf is rack mounted and has a safety cover that shields the electrical connections in the
power shelf rear.
The AC-input to DC-output connection supplies –48 VDC-out put po wer to the dial s helf PEMs. The
PEMs receive the –48V and transmit power to the filter module. Power flows through the filter
module to the backplane, w here it is distributed to the dial shel f controller card and dial shelf cards.
The AC-input power shelf includes two 2,000W AC-input power supplies that plug into a common
power backplane in the AC-input power shelf. A single AC-input power supply is capable of
powering a fully configured Cisco5814 dial shelf. The second power supply provides full
redundancy.
During normal operation, the dual AC-input power supplies provide au tomatic loadsharing, with
each power supply supporting 50 percent of the power load. When you remove one of the A C -input
power supplies, the remaining power supply immediately ramps up to full power and maintains
uninterrupted system power.
The AC-input power supplies are “hot-swappable,” allowing you to remove or replace a power
supply while the system is operating; system operation is not affecte d. Whenever possible, we
recommend that you connect each AC-input power supply to a separate AC po wer s ource.
TEMP Yellow Lights when the power shelf has shut down because of
overtemperature conditions.
I LIM Yellow Lights when the power shelf is overloaded and operating in a
current-limiting state.
The current limit LED lights fo r eit h er of the following
reasons:
•The power supply is operating in a current o verload
condition, such that the voltage is drawn below the fault
threshold level.
•The power shuts down due to a n o v ercur re nt con di ti on in th e
power supply. (When this occurs, both the I LIM LED and
the Fault LED light.)
Table1-9 Standard AC-Input Power Supply LEDs (continued)
LED Color Description