Power Module Fans - Cisco ASR 9901 Hardware Installation Manual

Power Module Fans

Power Module Fans
Each AC or DC power module is equipped with one fan that draws cooling air in through the front of the
power module and force warm air out through the air exhaust of the chassis:
• If the power source is within the required voltage range, the power supply fan remains on.
• If a fan fails:
For additional power supply troubleshooting information, see
103.
Note
For the RSP to communicate properly to a power module, input power to at least one of the two power modules
should be present.
Over-temperature Conditions
This console error message indicates that the system has detected an over-temperature condition or
out-of-tolerance power value inside the system:
Queued messages:
%ENVM-1-SHUTDOWN: Environmental Monitor initiated shutdown
The preceding message could also indicate a faulty component or temperature sensor. Enter the show
environment command or the show environment all command at the user EXEC prompt to display information
about the internal system environment. The information generated by these commands includes:
• Voltage measurements on each card from the DC-to-DC converter
• The +5 VDC for the I2C module
• Operating voltage for the fan tray
• Temperature measurements received by all sensors of RP and LC module as well as temperature
If an environmental shutdown results from an over-temperature or out-of-tolerance condition, the Fault
indicator on the power supply lights before the system shuts down.
Although an over-temperature condition is unlikely at initial system startup, make sure that:
• Heated exhaust air from other equipment in the immediate environment is not entering the chassis card
• You allow sufficient air flow by maintaining a minimum of 6 inches (15.24 cm) of clearance at both the
Cisco ASR 9901, ASR 9001, and ASR 9001-S Routers Hardware Installation Guide
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• Power module detects an internal over-temperature condition.
• Fault and Temp indicators light.
• Power module sends an over-temperature warning to the system and then power supply switchover
to the redundant power module.
measurements from sensors located in each power module
cage vents.
inlet and exhaust openings on the chassis and the power modules to allow cool air to enter freely and hot
air to be expelled from the chassis.
Troubleshooting the Installation
Troubleshooting the Power Subsystem, on page