Juniper Networks EX8208 manual Chassis Component Base Configuration Redundant Configuration

Complete Hardware Guide for EX8208 Ethernet Switches

Table 49: Chassis Power Consumption for N+N Configurations Running Junos OS Release 10.2 or Later

Chassis Component	Base Configuration	Redundant Configuration
Fan tray	700 W	700 W
SRE module	200 W	200 W
SRE module	—	200 W
SF module	100 W	100 W
Total	1000 W	1200 W

2.Calculate the maximum internal power consumption of the entire switch by adding 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

3.Calculate the maximum system power consumption by dividing the maximum internal 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

Calculating System Thermal Output for Your EX8208 Switch Configuration

Use the following procedure to calculate the system thermal output in British thermal units (BTU) per hour for your switch configuration.

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