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Cisco AS5850 Universal Gateway Hardware Installation Guide
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Chapter 1 Cisco AS5850 Product Overview
Online Insertion and Removal
DC-Input Power Specifications
The PEMFs provide –48 VDC power, which is distributed from the PEMF to the chassis backplane. No
damage occurs to the PEMFs if any or all outputs have no load (no load occurs when there are no cards
plugged into the backplane), or if the maximum input voltage is exceeded; however, input voltages that
exceed 75V eventually trip the PEMF 60A circuit breaker, and you might have to reset the breaker.
The Cisco AS5850 supports several types of logic cards with varying power requirements. As a result,
each logic card DC-to-DC converter system is isolated from the distributed –48 VDC power, creating a
more stable distributed power system.
Online Insertion and Removal
The Cisco AS5850 supports online insertion and removal (OIR), which allows you to remove and
replace a field-replaceable unit (FRU) while the system is operating, without affecting system operation.
Note
This section describes the mechanical functions of the system components and emphasizes the
importance of following the correct procedures to avoid unnecessary circuit board failures. This
section is for background information only.
Each FRU contains female connectors that connect to the system backplane. Each male backplane
connector comprises a set of tiered pins in three lengths. The backplane pins send specific signals to the
system as they make contact with the card connectors. The system assesses the signals it receives and
the order in which it receives them to determine whether to initialize a startup or shutdown procedure.
Each RSC card and feature card is designed with two ejector levers to be used when you install or remove
a card. The function of the ejector levers (see
Figure 3-4
) is to align and securely seat the card connectors
in the backplane and facilitate the installation and removal process.
Do not force the RSC cards or feature cards into the slot, because this can damage the card connector
pins if they are not aligned properly with the card connectors.
To avoid erroneous failure messages, you must allow at least 15 seconds for the system to reinitialize
and note current interface configurations before you remove or insert another RSC card or feature card
in the chassis.
Note
If you need to OIR the RSC serving as the primary clock source with a split backplane configuration,
you will need to switch the primary clock source to the other RSC as described in Chapter 4,
“Maintenance” in the
Cisco AS5850 Operations, Administration, Maintenance, and Provisioning
Guide
, available online at:
http://www.cisco.com/univercd/cc/td/doc/product/access/acs_serv/as5850/sw_conf/5850oamp/
index.htm
