IEEE 421.3:1997 (R2004)

Revision Standard - Superseded.
High-potential test voltages for excitation systems used with synchronous machines are established. Test voltages are established based on whether equipment is connected to the exciter power circuit or is electrically isolated from the exciter power circuit.

This standard applies to high-potential testing of complete excitation systems and their components for synchronous machines. The components of the excitation system are described in IEEE Std 421-1972, Criteria and Definitions for Excitation Systems for Synchronous Machines. Also included are auxiliary devices that are exposed to excitation system stresses. Examples of such auxiliary devices are temperature indicators, transducers, meters, etc. This standard does not cover the synchronous-machine field winding or field circuit breaker and discharge resistor.
This effort is to review the existing standard (IEEE Std 421B-1979) which is one of 5 standards in the 421 series on Excitation Systems for Synchronous Machines.