Juniper OCX1100, Hardware Manual

Page: 41 / 204

Do Not Install AIR IN (AFI) and AIR OUT (AFO) Components in the Same Chassis
Do not install power supplies and fan modules with different airflow labels (
AIR IN (AFI)
and
AIR OUT (AFO)
) in the same chassis. If the fan modules have
AIR IN (AFI)
labels, the
power supplies must also have
AIR IN (AFI)
labels; if the fan modules have
AIR OUT (AFO)
labels, the power supplies must also have
AIR OUT (AFO)
labels.
The labels on the power supplies and fan modules should match the labels on the switch
chassis.
Mixing components with AIR IN (AFI) and AIR OUT (AFO) labels in the same chassis
hampers the performance of the cooling system of the switch and leads to overheating
of the chassis.
Under normal operating conditions, the fan modules operate at a moderate speed.
Temperature sensors in the chassis monitor the temperature within the chassis.
CAUTION: The system raises an alarm if a fan module fails or if the ambient
temperature inside the chassis rises above the acceptable range. If the
temperature inside the chassis rises above the threshold temperature, the
system shuts down automatically.
Positioning the Switch
In front-to-back airflow, indicated by the label
AIR OUT (AFO)
on the fan modules and
power supplies, hot air exhausts through the vents on the rear panel of the switch. In
back-to-front airflow, indicated by the label
AIR IN (AFI)
on the fan modules and power
supplies, hot air exhausts through the vents on the front panel of the switch.
In data center deployments, position the switch in such a manner that the
AIR IN (AFI)
labels on switch components are next to the cold aisle, and
AIR OUT (AFO)
labels on
switch components are next to the hot aisle.
Related
Documentation
•
OCX1100 Switches Hardware Overview on page 3
•
Field-Replaceable Units in OCX1100 Switches on page 12
•
Installing a Fan Module in an OCX1100 Switch on page 105
•
Removing a Fan Module from an OCX1100 Switch on page 106
•
Prevention of Electrostatic Discharge Damage on page 167
21 Copyright © 2017, Juniper Networks, Inc.
Chapter 3: Cooling System and Airflow