Rockwell Automation has extended the power range of its PowerFlex 755 AC drives to 900 kW/1350 Hp and added 600/690 volt ratings. Building on the Allen-Bradley PowerFlex 755 high-power models, the new drives are suited for a variety of heavy industrial applications and provide users with increased application flexibility, advanced diagnostics and a common DC bus option.
The common DC bus option allows users to connect the PowerFlex 755 AC drive to a common DC-bus configuration, which takes advantage of different drive cycles to share energy. In this configuration, a DC bus acts as a common energy source that feeds energy from a generating load to a motoring load. The new frame size includes an embedded Ethernet port and five option slots that enables users to tailor it to their application. Option modules include I/O, feedback, safety, additional communications and an auxiliary power supply.
In addition to a "roll-out" design aimed to provide easier access to the drive, its converter and control pod also can remain in the unit while the inverter is rolled out. A firmware upgrade includes interior permanent magnet motor control, in addition to a “stop dwell” feature designed to prevent motors from coasting to a stop.
