Troubleshooting The T640 Power System - Juniper T640 Hardware Manual

Troubleshooting the T640 Power System

Problem
Copyright © 2010, Juniper Networks, Inc.
The following alarms, LEDs, and other conditions indicate a problem with the power
system:
If all power supplies have failed, the system temperature might have exceeded the
threshold, causing the system to shut down.
The following indicate a problem on a two-input 160-A DC power supply:
The and
DC OK CB OK
If the yellow CB TRIP LED lights but the power supply is not going through a startup
test, the power supply detects a fault (the power supply fails, does not have sufficient
airflow, or is not properly inserted).
The yellow
OVER TEMP
airflow to maintain proper temperature.
The following indicate a problem on a three-input 240-A DC power supply or four-input
240-A DC power supply:
The blue LED is off.
DC OK
If the blue LED blinks but is not going through a startup test, the power supply
DC OK
detects a fault (the power supply fails, does not have sufficient airflow, or is not
properly inserted).
The yellow OVER TEMP
airflow to maintain proper temperature.
The
INPUT PRESENT
power.
If the
INPUT PRESENT
breaker is off.
The following indicate a problem on a three-phase delta or wye AC power supply:
The green AC OK LED is off when the power supply is not receiving source AC power.
The blue LED is off.
DC OK
If the blue DC OK LED blinks but is not going through a startup test, the power supply
detects a fault (the power supply fails, does not have sufficient airflow, or is not
properly inserted).
The yellow
OVER TEMP
airflow to maintain proper temperature.
Chapter 16: Troubleshooting T640 Router Hardware Components
LEDs are off.
LED lights when the power supply is not receiving enough
LED lights when the power supply is not receiving enough
LED is off, indicating that the input is not receiving source DC
LED is lit but the LED is off, it indicates that the circuit
CB ON
LED lights when the power supply is not receiving enough
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