Juniper QFX5100, Руководство по оборудованию

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Figure 21: 2 U AC Power Supply in a QFX5100-96S Switch
The power supply provides FRU-to-port or port-to-FRU airflow depending on the product
SKU you purchase. On legacy switches, or switches with an LCD, this airflow is called
back-to-front and front-to-back. The power supplies either have labels on the handles
that indicate the direction of airflow or they have color-coded handles with a fan icon.
See
Figure 22 on page 36 for an example of the power supply. Either a power supply has
the label
AFI
or a blue handle, which denotes FRU-to-port airflow. A power supply with
the label
AFO
or a gold-colored handle denotes port-to-FRU airflow.
Figure 22: Power Supply Handle Detail
1— Fan icon on handle
CAUTION: Verify that the airflow direction on the power supply handle
matches the direction of airflow in the chassis. Ensure that each power supply
you install in the chassis has the same airflow direction. If you install power
supplies with two different airflow directions, Junos OS raises an alarm. If
you need to convert the airflow pattern on a chassis, you must change out
all the fans and power supplies at one time to use the new direction.
Table 11 on page 37 shows the different power supplies and their direction of airflow.
Copyright © 2014, Juniper Networks, Inc. 36
QFX5100 Switch Hardware Guide