Rockwell Automation 2364E Non-Regenerative DC Bus Supply Unit (NRU) - Manual (Page 18)

Publication 2364E-5.01 April 2002
1-4 Overview
Six-Pulse, Full-Wave, 3-Phase-Diode-Bridge Rectifier Unit
The bridge rectifier converts the 3-phase AC power to DC.
DC Bus Choke
The DC bus choke reduces peak currents in the AC line and the
bridge circuit. The DC bus choke also reduces line harmonics.
Control Power Transformer
This transformer steps down 2 phases of the 3-phase AC line voltage
to a single-phase, 115V AC control signal.
Primary and Secondary Control Transformer Fusing
Control transformer fusing protects the transformer and control
circuitry from excessive currents.