Juniper Networks EX8208 - Manual (Page 141)

This topic describes these tasks:
• Calculating the Power Consumption of Your EX8208 Switch Configuration on page 115
• Calculating System Thermal Output for Your EX8208 Switch Configuration on page 116
• Calculating the Number of Power Supplies Required for Your EX8208 Switch
Configuration on page 117
Calculating the Power Consumption of Your EX8208 Switch Configuration
Use the following procedure to determine the maximum power you need to supply to
the switch. To calculate maximum system power consumption, you first determine the
combined maximum internal power requirements of all the switch components and then
divide this result by the power supply efficiency.
To calculate maximum system power consumption:
1. Determine the maximum power consumption of the base chassis components (that
is, the components other than the line cards):
• Use Table 48 on page 115 if your switch is configured for N+1 power redundancy or
if your switch is configured for N+N power redundancy and is running Junos OS
Release 10.1 or earlier.
• Use Table 49 on page 116 only if your switch is running Junos OS Release 10.2 or
later and power management is configured for N+N power redundancy.
NOTE: In Junos OS Release 10.2 or later, if power management is configured for N+N
redundancy, the maximum fan speed is lowered, reducing the chassis’ maximum power
consumption.
Table 48: Chassis Power Consumption for N+1 Configurations and for
N+N Configurations Running Junos OS Release 10.1 or Earlier
Redundant Configuration Base Configuration Chassis Component
1100 W 1100 W Fan tray
200 W 200 W Switch Fabric and Routing Engine (SRE)
module
200 W — Second SRE module
100 W 100 W Switch Fabric module
1600 W 1400 W Total
115 Copyright © 2010, Juniper Networks, Inc.
Chapter 7: Planning Power Requirements