Juniper TX MATRIX PLUS Hardware Manual page 325

Solution
Copyright © 2010, Juniper Networks, Inc.
If a power supply is not functioning normally, perform the following steps to diagnose
and correct the problem:
Check the LEDs on each seven-input 420-A power supply faceplate.
1.
PEM OK power supply LED is off—Determine if there is a red alarm LED on the craft
interface.
power supply LED is off but no red alarm condition exists—Verify that
PEM OK
LEDs are lit steadily green and that the
PRESENT
that the circuit breakers are switched to the on position (
LED on a power supplies is lit— the power supply has failed, does not have
FLT
sufficient airflow to maintain proper temperature, or is not properly seated in the
chassis. It might also indicate that the power supply is going through a startup test
Verify that the fan trays and air filters in the chassis are functioning and providing
sufficient airflow through the chassis.
Verify that the power supply is properly seated in the chassis.
Check the LEDs on the craft interface:
2.
Verify that the PEMS OK
Red alarm or yellow alarm LED is lit—Use the
determine the source of the problem. The Junos OS constantly updates the screen
with status information for each component. See Table 50 on page 293 for a
description of power supply alarms and how to recover from alarm conditions.
NOTE: On the display and in the CLI, the power supplies are referred to
as PEM0 and
Issue the
3. show chassis environment pem sfc 0
, DC Input is , and the DC output for each channel on each PEM are equal.
Online OK
NOTE: The current sharing between PEMs relies on equal voltages at the
input terminals of the PEMs. The TX Matrix Plus router system power is
divided into multiple load zones. The input voltage on each input should
match the voltage on the same input on the other power supply. However,
if the voltages do not match, the TX Matrix Plus router operates normally
as long as the DC input voltages are within the operating range.
user@host> show chassis environment pem sfc 0
sfc0-re0:
--------------------------------------------------------------------------
PEM 0 status:
State
Temperature
Chapter 21: Troubleshooting TX Matrix Plus Hardware Components
PWR ON
is lit and that the FAIL LED is not lit.
show chassis alarms
PEM1 , from left to right.
to verify that the power supplies are
Online
35 degrees C / 95 degrees F
INPUT
LEDs are lit indicating
| ).
command to
291