Each AC power supply comes with a power retainer that holds the power cord in place.See Figure 22 on page 35. The power retainer has a clip and an adjustment nut. TheL-shaped ends of the clip hook into the bracket holes on each side of the AC applianceinlet on the faceplate. The adjustment nut holds the power cord in the correct position.For instructions for installing the power retainer, see “Connecting AC Power to a J-EX8200Switch” on page 130.Figure 22: Power Retainer for an AC Power SupplyEach power supply connects to the backplane in a J-EX8208 switch . The backplanedistributes the output power produced by the power supplies to different switchcomponents. Each AC power supply provides power to all the components in the switch.Each power supply has its own fan and is cooled by its own internal cooling system. Theairflow is from the front of the power supply to the back. Hot air exhausts from the rearof the chassis.A J-EX8208 switch supports 2000 W AC power supplies.The 2000 W AC power supply supports both the low-line (100–120 VAC) and the high-line(200–240 VAC) AC power configurations. In both cases, the output is 52 VDC. The outputpower is 1200 W for low-line input and 2000 W for high-line input.The 3000 W AC power supply supports only the high-line (200–240 VAC) AC powerconfiguration. The output is 52 VDC. The output power is 3000 W for high-line input.N+1 Redundancy Configuration of AC Power SuppliesN+1 redundancy configuration is required for normal operation of J-EX8200 switches. Inan N+1 redundancy configuration, if one power supply fails or is removed, the remainingpower supplies continue to supply power for the switch without interruption.The number and type of line cards installed in the switch and the input voltage determinethe number of power supplies needed (N) for a switch. You must then install an additionalpower supply to meet the required N+1 redundancy configuration.Table 20 on page 36 lists the N+1 power requirements of J-EX8208 switch configurationsthat use 2000 W AC power supplies.35Chapter 2: Component Descriptions
