Juniper MX2010, Hardware Manual

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NOTE: For midpoint impedance grounded source, the CLI display of the input voltage is
inaccurate for the input source with lower input voltage. For example, if one source is
+/-120V, and the other source is +/-125V, the CLI input voltage display is 250 V for one
input, and is 245 V (should be 240 V) for the other.
8. If a red alarm condition occurs, issue the show chassis alarms command to determine the source of
the problem.
9. If all PSMs 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.
To restart a high-capacity AC power supply after a shut down due to an over-temperature situation:
1. Move the power switch on the power supply to the off (o) position.
2. Turn off power to where the AC line goes into the power distribution module (PDM) area.
3. Wait for the power supply LEDs to fade out and for the fans inside the power supply to shutdown.
This can take up to 10 seconds.
CAUTION: Do not attempt to power-on the power supply if the LED is still lit
and the fan is still running. If you do, the router will not reboot.
4. Turn on power to where the AC line goes into the power distribution module (PDM) area.
5. Move the power switch on the power supply to the on (|) position.
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