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Maintaining the T4000 Power System



For optimum router performance, verify the condition of the power supplies and grounding.


On a regular basis:

  • Check the red and yellow alarm LEDs and the LCD on the craft interface. Power supply failure or removal triggers an alarm that causes one or both of the LEDs to light and an error message to appear on the LCD. You can display the associated error messages by issuing the following CLI command:

    user@host> show chassis alarms

    For a list of possible alarm messages, see Troubleshooting the T4000 Power System.

  • Make sure that the DC power cables are arranged so that they do not obstruct access to other router components.

  • The power supplies require an unobstructed airflow at both the front and rear of the chassis. Periodically check the site to ensure that both the air intake at the bottom front of the chassis and the exhaust from the power supply faceplates are unobstructed.

  • Periodically inspect the site to ensure that the grounding and power cables connected to the router are securely in place and that no moisture is accumulating near the router. To review grounding and site wiring requirements for the router, see T4000 DC Power Cable and Lugs Specifications and T4000 Chassis Grounding Cable and Lug Specifications.

  • Use the show chassis environment pem command to verify the status of the power supplies.

  • Routinely check the status LEDs on the power supply faceplates to verify that the power supplies are functioning normally. During normal operation:

    • The blue DC OK LEDs light to indicate that the power supplies are functioning normally.

    • Each green INPUT PRESENT LED on a DC power supply lights when the input is receiving source DC power.