Replace A Fan Tray; Before Hot-Swapping A Fan Tray; Replace Fan Tray - Cisco 4451 ISR Hardware Installation Manual

Replace a Fan Tray

Care should be taken while removing the power supplies and power inverters (especially in boost
Warning
mode of operation). If the total power consumption is higher than can be supported by one power
supply alone and in this condition a power supply is removed, the hardware can be damaged. This
may then result in the system being unstable or unusable.
The following messages are expected behavior when you try to reload or insert a PoE supply in a router
with Ethernet Switch Network Module:
*Jul 21 22:35:23.868: %IOSXE_PEM-6-INSPEM_FM: PEM/FM slot POE0 inserted
Upon PoE converter power supply insertion, inline power supply restores automatically in the router.
After the insertion, resets are needed for the switch modules in the router for the PoE supply to work
properly.
If there are two PoE supplies, the power supplies can operate in a boost mode or redundant mode. In a
boost mode, the total power supplied is a sum of the two power supplies capacity. In a redundant mode,
if one of the PoE supply fails, the other PoE will supply power.
Replace a Fan Tray
The Cisco 4000 Series ISRs have hot-swappable fan trays that are field replaceable units (FRUs). The
fan tray includes all of the router fans in one assembly. If a fan fails, replace the tray using a flat-blade
or Phillips screwdriver.
Note
The Cisco 4331 ISR and Cisco 4321 ISR do not have hot-swappable fan trays.

Before Hot-Swapping a Fan Tray

Before hot-swapping a fan tray, read the safety precautions below.
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Replace Fan Tray

To replace the fan tray:
Note
If hot-swapping the fan tray, it is recommended to complete the operation within two minutes to ensure
the router remains within operating temperature.
Step 1
Remove the bezel. The bezel is secured with snap latches. To remove the bezel, hold the top and bottom
and pull the bezel.
Hardware Installation Guide for Cisco 4000 Series Integrated Services Routers
6-58
Read the entire procedure and have the required tools available.
Do not attempt the hot-swap in ambient air temperature above 90°F (32°C).
Do not attempt the hot-swap at an altitude above 6000 feet (1829 meters).
When the router is being operated, it is recommended to change the fans in the router within 2
minutes to ensure the router does not overheat:
Chapter 6 Install and Upgrade Internal Modules and FRUs
OL-32185-02