DC Power Supply in an EX8200 Switch

The DC power supplies in EX8200 switches are hot-removable and hot-insertable field-replaceable units (FRUs).

Note: EX8208 switches support 2000 W DC power supplies. EX8216 switches support 3000 W DC power supplies.

You can install up to six DC power supplies in an EX8200 switch. Power supplies are installed at the bottom of the chassis in slots labeled PSU 0 through PSU 5 (left to right). See Slot Numbering for an EX8208 Switch and Slot Numbering for an EX8216 Switch. All power supplies are accessible from the front of the chassis.

Warning: The switch is pluggable type A equipment installed in a restricted-access location. It has a separate protective earthing terminal provided on the chassis. This separate protective earthing terminal must be permanently connected to earth ground.

Note: EX8216 switches have two protective earthing terminals provided on the chassis, one on the left side of the chassis and the other on the rear of the chassis. Only one of these protective earthing terminals needs to be permanently connected to earth ground. See Chassis Physical Specifications of an EX8216 Switch for the location of the protective earthing terminals.

Note: DC power supplies are shipped only in the redundant configuration of EX8200 switches. See EX8208 Switch Configurations for details about different EX8208 switch configurations. See EX8216 Switch Configurations for details about different EX8216 switch configurations.

Each DC power supply weighs approximately 7 lb (3.2 kg) and has two independent pairs of DC input lugs (A: –48V A: RTN and B: – 48V B: RTN ) on the front of the power supply. Each power supply also has an Enable switch, a fan, and four LEDs on the faceplate that indicate the status of the power supply. See Figure 1.

Figure 1: DC Power Supply

Note: A 2000 W DC power supply requires a dedicated 60 A circuit breaker for each input DC feed. A 3000 W DC power supply requires a dedicated 100 A circuit breaker for each input DC feed.

Each DC power supply connects to the backplane in an EX8208 switch and to the midplane in an EX8216 switch. The backplane in an EX8208 switch and the midplane in an EX8216 switch distribute the output power produced by the power supplies to different switch components. Each DC power supply provides power to all the components in the switch.

The output of each 2000 W DC power supply is 52 VDC. The output power is 2000 W.

The output of each 3000 W DC power supply is 52 VDC. The output power is 3000 W.

A DC power supply works with only one input DC feed connected. It is able to deliver the full output power to all chassis components with only one DC feed connected.

Each DC power supply has its own fan and is cooled by its own internal cooling system. The airflow is from the front of the power supply to the back. Hot air exhausts from the rear of the chassis.

The minimum power configuration required by an EX8200 switch is an N+1 power configuration. In an N+1 power configuration, if one power supply fails or is removed, the remaining power supplies continue to supply power for the system without interruption.

The configuration type of the switch and the input voltage determine the number of power supplies needed (N) for a switch. You must install an additional power supply to meet the required N+1 power redundancy configuration. The DC power supplies each provide independent A and B power feeds, so that dual power feed redundancy is available even in an N+1 configuration. See EX8208 Switch Configurations for details about different EX8208 switch configurations. See EX8216 Switch Configurations for details about different EX8216 switch configurations.

The tables in this section list the N+1 power requirements of different EX8200 switch configurations:

• Table 1—Lists the N+1 power requirements of EX8208 switch configurations that use 2000 W DC power supplies.
• Table 2—Lists the N+1 power requirements of EX8216 switch configurations that use 3000 W DC power supplies.