INTRODUCTION

The DXCB-2 De-Excitation/Crowbar Module protects the generator field

and exciter circuits by providing a low impedance path for currents that

would otherwise cause excessively high transient voltage or damaging

arcs. A DXCB-2 module can be operated in one of two modes: de-

excitation (DX) or crowbar (CB).

In DX mode, the DXCB-2 module provides a path for the generator field

current when its field breaker is opening or when the normal path is not

available.

In CB mode, the DXCB-2 module provides a low-resistance path for large

positive voltages across the generator field and exciter bridge. Generator

pole-slip is one source of high voltage.

The enclosure of the DXCB-2 offers electric shock protection from incidental

contact. An identical footprint and functional compatibility make for simple

replacement of a DXCB with a DXCB-2.