Systems are referred to as dual AC system because the power subsystem in each cabinet can accommodate power from two separate power sources.
Each processing and storage cabinet has either two AC feeder boxes (one on each side of the cabinet), or four AC feeder boxes (two on each side of the cabinet).
- The AC feeder boxes on one side of the cabinet must be connected to one power source, and the AC feeder boxes on the other side of the cabinet must be connected to a separate power source.
- By default:
- If a cabinet has two AC feeder boxes, both share current.
- If a cabinet has four AC feeder boxes, the top two AC feeder boxes share current, and the bottom two AC feeder boxes share current.
- If the power source connected to the AC feeder boxes on one side of the cabinet is lost, the current on the AC feeder boxes connected to the remaining power source will increase to take over power for the lost source; however, the system will experience some operational degradation.
Note that power connections to some Ethernet switches are not redundant. A system that loses operation on some of its power cords will lose operation on Ethernet switches that are connected to a single power supply.