The AC-input power supplies of all Cisco Catalyst 4500 Series switches require a single-phase source AC. The source AC can be out of a phase between multiple power supplies or multiple AC-power plugs on the same power supply, because all AC power supply inputs are isolated. Each chassis power supply must have a dedicated branch circuit, which is:
- 15 A or 20 A for North America
- Circuits sized to local and national codes for international locations
In order to support the 4200W AC power supply, the Cisco Catalyst 4500 Series switch requires at least Cisco IOS Software Release 12.2(25)EWA.