The DCFB board provides control-level power to a dc drive or exciter and 115 V ac that is typically used to power enclosure cooling fans. The DCFB includes the following circuits:
Control-level power supplies (+5, ± 15, and ± 24 V dc)
Motor or generator field power circuits (except the SCR module)
Driver circuits for the armature SCR gate pulse generators
Circuits to instrument numerous ac line and dc motor or generator signals, including:
– Armature current and voltage
– Field current
– Ac line current
– Ac line voltage magnitude and phase sequence
A printed wiring board is identified by an alphanumeric part number imprinted on it. For example, the Power Supply Board is marked with part number:
The DS200DCFB portion is the base number that identifies the printed wiring board, in this case, the Power Supply Board. The r and u digits are alphabetic characters that indicate the board revision level. The r digit reflects a functional change that is not downward compatible. It is essentially a new catalog number. The u digits represent revision levels that are downward compatible.
The G# identifies a group, which is a variation of a particular board.
The DCFB board has only one group, G1.