22 | Power Supplyw w w . d e l l . c o m | s u p p o r t . d e l l . c o mAC Power Supply UnitsThe 2500W AC Power Supply Unit is capable of operating at either 100 VAC or 220 VAC. If the systemis connected to a 100 VAC power supply, each unit provides up to 1500W, and three power supplymodules are required to power the system; four power supply units are required for power supplyredundancy.If the system is connected to a 220 VAC power supply, two power supply units are required for providingpower to the system, three power supply units are required for power supply redundancy, and four powersupply units are required for full facility redundancy.Full facility redundancy requires two independent power sources (feeds) with two power supplies oneach feed. Each independent power source should have a dedicated circuit breaker sized in accordancewith your local electrical codes.CAUTION: Before removing and replacing a power supply unit, determine if the E600i is in full redundancy ornon-redundant mode. Operating in non-redundant mode will require a complete system power off whenremoving and replacing a power supply.NOTE: Do not mix power supplies. Installing a 2500W-AC2 power supply into a chassis with 2500W-ACpower supplies already installed may result in unpredictable behavior. FTOS version 8.3.1.2 and later willdeclare an alarm when the PSUs are mixed.Figure 6-2. AC Power Supply UnitPower SwitchStatus LEDGreen Power OnAmber FaultHandleCord RetainerLocking Screws (2)Power Cord SocketThumb Screw