Juniper EX4200-24T

The Switch Displays the “Unsupported PSU” Alarm
Problem Description: The “Unsupported PSU” alarm appears on the EX4200-24PX or the
EX4200-48PX switch.
Symptoms:
• A 930 W AC power supply is installed in the switch, but no power is detected on PoE+
ports.
• The Alarm (ALM) LED lights red and when you check the alarm status using the show
chassis alarms command, the “Unsupported PSU” alarm is displayed as shown below:
user@switch> show chassis alarms
1 alarm currently active
Alarm time Class Description
2011-02-14 08:34:39 UTC Unsupported PSU
Cause The power supply you have installed is not compatible with the switch.
EX4200-24PX and EX4200-48PX switches do not support the 930W (EX-PWR-930-AC)
or the 600 W (EX-PWR-600-AC) AC power supplies that are used in the EX4200-48P
and the EX4200-24P switch models. EX4200-24PX and EX4200-48PX switches work
only with the power supplies labeled EX-PWR2-930-AC or EX-PWR3-930-AC. All EX4200
switches support EX-PWR2-930-AC and EX-PWR3-930-AC power supplies.
Solution Check the label of the power supply you have installed in the switch. You can find the
label on the top of the power supply (see “Removing a Power Supply from an EX4200
Switch” on page 185). If it is an incompatible power supply, remove it and install the correct
power supply.
Related
Documentation
• Installing a Power Supply in an EX4200 Switch on page 183
• Power Supply in EX4200 Switches on page 33
239Copyright © 2017, Juniper Networks, Inc.
Chapter 25: Troubleshooting Switch Components