Juniper EX4200 Series, Hardware Manual, Page: 55 / 344

CHAPTER 4
Power Supplies
• Power Supply in EX4200 Switches on page 33
• AC Power Supply LEDs in EX4200 Switches on page 37
•
DC Power Supply LEDs in EX4200 Switches on page 38
Power Supply in EX4200 Switches
The power supply in EX4200 switches is a hot-removable and hot-insertable
field-replaceable unit (FRU) that you can install on the rear panel without powering off
the switch or disrupting the switching function. EX4200 switches have an internal
redundant power supply, making the power supply in EX4200 switches fully redundant.
All the EX4200 switch models, except the EX4200-24F-S and EX4200-48T-S switches
are shipped with one power supply pre-installed in the rear panel of the switches.
EX4200-24F-S and EX4200-48T-S switches are not shipped with pre-installed power
supplies; you must order them separately.
NOTE: This topic uses the term PoE to refer to both PoE and PoE+ unless
there is a need to distinguish between the two.
EX4200 switches use power supplies that provides two DC output voltages: 12 V for
system and logic power and 48–51 V (or higher, to compensate for voltage drops along
the path from the power supplies to the RJ-45 connector) for PoE ports.
NOTE: After powering on the switch, wait for at least 60 seconds before
powering it off. After powering off the switch, wait for at least 60 seconds
before powering it back on.
After the switch has been powered on, it can take up to 60 seconds for status
indicators—such as LEDs on the power supply,
show chassis
command output,
and messages on the LCD panel—to indicate that the power supply is
functioning normally. Ignore error indicators that might appear during the
first 60 seconds.
33 Copyright © 2015, Juniper Networks, Inc.