1-19
Catalyst 3650 Switch Hardware Installation Guide
OL-29734-01
Chapter 1 Product Overview
Rear Panel
For information about replacing a power supply module, wiring a DC power supply module, and module
specifications, see Chapter 3, “Power Supply Installation,” and Appendix A, “Technical Specifications.”
Fan Modules
The switch has three internal hot-swappable 12-V fan modules. The air circulation system consists of
the fan modules and the power supply modules. The airflow patterns vary depending on the power supply
configuration.
Figure 1-8 shows the airflow patterns for the 24- and 48-port switches. The blue arrow shows cool air
flow, and the red arrow shows warm air flow. When the fan modules are operating properly, a green LED
is on at the top left corner of the fan assembly (viewed from the rear). If the fan fails, the LED turns to
amber. The switch can operate with two operational fans, but the failed fan should be replaced as soon
as possible to avoid a service interruption due to a second fan fault.
Note Three fans are required for proper cooling.
Figure 1-8 24- and 48-Port Switch Airflow Patterns
For information about installing a fan module and fan specifications, see Chapter 4, “Installing the Fan,”
and Appendix A, “Technical Specifications.”
DC-Power Supply Module LEDs
DC OK Description PS OK Description
Off No DC input power. Off Output is disabled, or input is
outside operating range (DC LED
is off).
Green DC input power present. Green Power output to switch active.
Red Output has failed.
Table 1-13 Switch Power Supply Module LEDs (continued)
Table 1-14 Switch Fan Module
Fan Module Description
FAN-T1= Fan module
C
a
t
alyst
3650
48P
oE
+
4X
1
G
347812
01
X
13
X
12
X
24
X
25
X
36X
37X
48X
