IEEE 421.3:2016

Revision Standard - Active.
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 421.1(TM). Auxiliary devices connected to either the input or output side of the rectifier bridge are exposed to similar excitation system stresses and are included in the requirements of this standard. Examples of such devices include temperature indicators, transducers, meters, field circuit breaker, discharge resistor, crowbar, etc. This standard does not cover the synchronous machine field winding.
The purpose of this standard is to provide requirements and specific directions for the high-potential testing of complete excitation systems and their components using the most recent information manufacturers have made available.