Juniper MX240 Hardware Manual page 357

Copyright © 2019, Juniper Networks, Inc.
If a DC power supply is correctly installed and functioning normally, the
, and
INPUT OK BRKR ON
Issue the CLI show chassis environment pem
power supply modules. As shown in the sample output, the value
labeled indicates that each power supply is functioning normally:
State
user@host> show chassis environment pem
PEM 0 status:
State
Temperature
DC output
PEM 2 status:
State
Temperature
DC output
If a power supply is not functioning normally, perform the following steps to diagnose
and correct the problem:
If a red alarm condition occurs, issue the
the source of the problem.
Check that the AC input switch (
that the power supply is receiving power.
Verify that the source circuit breaker has the proper current rating. Each power supply
must be connected to a separate source circuit breaker.
Verify that the AC power cord or DC power cables from the power source to the router
are not damaged. If the insulation is cracked or broken, immediately replace the cord
or cable.
Connect the power supply to a different power source with a new power cord or power
cables. If the power supply status LEDs indicate that the power supply is not operating
normally, the power supply is the source of the problem. Replace the power supply
with a spare.
If all power supplies have failed, the system temperature might have exceeded the
threshold, causing the system to shut down.
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 supplies provide power to the
router, and you can still view the system status through the CLI or display.
LED's light steadily.
command to check the status of installed
Online
OK
OK
Online
OK
OK
show chassis alarms
— ) or DC circuit breaker (
Chapter 5: Troubleshooting Hardware
PWR_OK
in the rows
Online
command to determine
| ) is in the on position and
,
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