Juniper EX4550 - Figure 27: DC Power Supply for an EX4550 Switch; Table 22: Airflow Direction in DC Power Supply Used in EX4550 Switches

Figure 27: DC Power Supply for an EX4550 Switch
g050210
2
3
1
AFI
3—1— Ejector leverHandle
2—Terminal block
The DC power supply in EX4550 switches is a hot-insertable and hot-removable
field-replaceable unit (FRU): You can install it without powering off the switch or
disrupting the switching function.
Two variants of DC power supplies are available, each with a different airflow:
•
Back-to-front airflow, indicated by AFI label
•
Front-to-back airflow, indicated by AFO label
Each power supply has a label AFI or AFO and an arrow on the handle that depicts the
direction of airflow (see Figure 28 on page 46).
Table 22 on page 45 shows the DC power supply model numbers and the direction of
airflow in them.
Table 22: Airflow Direction in DC Power Supply Used in EX4550 Switches
Direction of AirflowLabel on Power SupplyModel Number
Back-to-front—air intake to cool the chassis is through the
vents on the rear panel of the chassis, and hot air exhausts
through the vents on the front panel of the chassis.
AFIJPSU-650W-DC-AFI
Front-to-back—air intake to cool the chassis is through the
vents on the front panel of the chassis, and hot air exhausts
through the vents on the rear panel of the chassis.
AFOJPSU-650W-DC-AFO
45Copyright © 2015, Juniper Networks, Inc.
Chapter 4: Power Supplies