• Supported Platforms
• TX Matrix Routers

• Related Topics
• TX Matrix Craft Interface Overview
• Replacing a TX Matrix Two-Input 160-A DC Power Supply
• Replacing a TX Matrix Three-Input 240-A DC Power Supply

Troubleshooting the TX Matrix Power System

Problem

The following alarms, LEDs, command output, and conditions indicate a problem with the power system:

• The yellow CB TRIP LED lights on the two-input 160-A power supply faceplate to indicate that the power supply detects a fault (the power supply fails, does not have sufficient airflow, is going through a startup test, or is not properly inserted).
• The blue DC OK LED blinks on the three-input 240-A power supply faceplate to indicate that the power supply detects a fault (the power supply fails, does not have sufficient airflow, is going through a startup test, or is not properly inserted).
• The yellow OVER TEMP LED lights on the power supply faceplate when the two-input 160-A power supply or the three-input 240-A power supply is not receiving enough airflow to maintain proper temperature.

During normal operation:

• If the green CB ON and the blue DC OK LEDs on each two-input 160-A power supply faceplate are on, the power source is good and the power supplies are functional.
• The CB ON LED on the faceplate of each two-input 160-A power supply faceplate or three-input 240-A power supply lights when the circuit breaker is functioning.
• If the green INPUT PRESENT and the blue DC OK LEDs are on each three-input 240-A power supply, the power source is good and the power supplies are functional.
• The INPUT PRESENT LEDs light on each three-input 240-A power supply when the input is receiving source DC power.

Solution

To verify that a power supply is functioning normally:

• Check the LEDs on each two-input 160-A power supply faceplate.

  • If the green CB ON and the blue DC OK LEDs are on, the power source is good and the power supplies are functional.
  • The CB ON LED on the power supply lights when the circuit breaker is functioning.
  • The DC OK LED lights when the power supply is receiving source DC power.
  • The yellow CB TRIP LED lights when the power supply detects a fault (the power supply fails, does not have sufficient airflow, is going through a startup test, or is not properly inserted).
  • The yellow OVER TEMP LED lights when the power supply is not receiving enough airflow to maintain proper temperature.

• Check the LEDs on each three-input 240-A power supply faceplate.

  • If the green INPUT PRESENT and the blue DC OK LEDs are on, the power source is good and the power supplies are functional.
  • The INPUT PRESENT LED lights when the input is receiving source DC power.
  • The CB ON LED on the power supply lights when the circuit breaker is on.
  • The blue DC OK LED blinks when the power supply detects a fault (the power supply fails, does not have sufficient airflow, is going through a startup test, or is not properly inserted).
  • The yellow OVER TEMP LED lights when the power supply is not receiving enough airflow to maintain proper temperature.
• Check the display on the craft interface. The Junos OS constantly updates the screen with status information for each component.

  Note: On the display and in the CLI, the power supplies are referred to as PEM0 and PEM1, from top to bottom.

If a power supply is not functioning normally, perform the following steps to diagnose and correct the problem:

• If the DC OK power supply LED is off, check the red alarm LED on the craft interface. The Junos OS monitors the system temperature, and if it exceeds a certain limit, the software triggers a red alarm, a condition that shuts down the power supplies.
• If a red alarm condition occurs, check the display on the craft interface to determine the source of the problem.

  Note: If the system temperature exceeds the threshold, the Junos OS shuts down all power supplies so that no status is displayed. The Junos OS also can shut down one of the power supplies for other reasons. In this case, the remaining power supply assumes the load, and you can still view the system status through the CLI or display.

• If the DC OK power supply LED is off and no red alarm condition exists, check that the circuit breaker is switched to the on position (|).
• Verify that the source circuit breaker has the proper current rating. Each input on each power supply must be connected to a separate power source.
• Verify that the power cables from the power source to the TX Matrix router are not damaged. If the insulation is cracked or broken, immediately replace the cable.
• Connect the power supply to a different power source with a new power cable. If the power supply DC OK LED still does not light, the power supply is the source of the problem. Replace the power supply with a spare.
• If the DC OK LED on the installed spare lights, the replaced power supply is faulty, and you should return it for replacement, as described in Returning a TX Matrix Router or Component.
• If the OVER TEMP LED on one of the power supplies lights, check the fans and air filters to be sure they are functioning and providing sufficient airflow through the chassis.
• If you cannot determine the cause of the problem or need additional assistance, see Contacting Customer Support.