Table 50: Chassis Power Consumption For N+N Configurations Running Junos; Configuration - Juniper EX8208 Complete Hardware Manual

Complete Hardware Guide for EX8208 Ethernet Switches
Calculating System Thermal Output for Your EX8208 Switch Configuration
110
Table 50: Chassis Power Consumption for N+N Configurations Running
Junos OS Release 10.2 or Later
Chassis Component
Fan tray
SRE module
SRE module
SF module
Total
Calculate the maximum internal power consumption of the entire switch by adding
2.
in the power requirements of each line card.
For example, for a switch fully loaded with 8-port SFP+ line cards and using N+1 power
redundancy, the maximum internal power consumption:
= (chassis watts) + 8 (8-port SFP+ line card watts)
= (1600 W + 8 (450 W))
= (1600 W + 3600 W)
= 5200 W
Calculate the maximum system power consumption by dividing the maximum internal
3.
power consumption by the efficiency of the power supply. This accounts for the loss
of energy within the power supply.
NOTE: The efficiency of a 2000 W AC power supply is approximately 90
percent when input is high-voltage line (200–240 VAC).
The efficiency of a 2000 W AC power supply is approximately 87 percent
when input is low-voltage line (100–120 VAC).
For example, for a switch fully loaded with 8-port SFP+ line cards and using N+1 power
redundancy with high-voltage line input, the maximum system power consumption:
= (maximum internal power consumption) / (power supply efficiency)
= (5200 W) / (0.90)
= 5778 W
Use the following procedure to calculate the system thermal output in British thermal
units (BTU) per hour for your switch configuration.
Base Configuration
700 W
200 W
—
100 W
1000 W
Copyright © 2010, Juniper Networks, Inc.
Redundant Configuration
700 W
200 W
200 W
100 W
1200 W