IEEE 1668-2014

This document is a non-industry-specific recommended practice for voltage-sag ride-through performance and compliance testing for all electrical and electronic equipment connected to low-voltage power systems (with nominal/rated voltage less than 1000 V) that can experience malfunction or shutdown as a result of reductions in supply voltage lasting less than one minute. The recommended practice includes defining minimum voltage-sag immunity requirements based on actual voltage-sag data. A clause dedicated to the detailed analysis of voltage sags experienced by end users provides insight into real-world voltage sags. Testing procedures and requirements for test equipment are clearly defined within this document to reflect the electrical environment, including single-phase, two-phase, and three-phase, balanced and unbalanced voltage sags. The recommended practice also defines requirements for certification and test reporting, including characterization of voltage-sag ride-through equipment.

The purpose of this recommended practice is to clearly define test methods and ride-through performance for determining the sensitivity of electrical and electronic equipment to voltage sags. Analysis of real-world sags provides the foundation for both test methods and performance criteria, aligning themselves as closely as possible to the end user’s electrical environment. The recommended practice will define the characteristics in terms of the depths/magnitudes, durations, phase angles, and vectors of voltage sags required to relate to real-world voltage sags. The recommended practice will show how different voltage-sag testing methods can be used to simulate real-world sags. End users will be able to use the recommended practice in their purchase specifications to ensure the required level of equipment performance. In addition, end users can use the voltage-sag criteria as a performance benchmark for existing equipment. This recommended practice can be used to provide a benchmark that can be used to identify equipment that has enhanced ride-through characteristics.

New IEEE Standard - Superseded. A trial-use, non-industry-specific recommended practice for voltage sag and short interruption ride-through performance and compliance testing for all electrical and electronic equipment connected to low-voltage power systems that can experience malfunction or shutdown as a result of reductions in supply voltage lasting less than one minute is detailed in this document. Testing procedures and requirements for test equipment are clearly defined within this document to reflect this electrical environment, including single-phase, two-phase, and three-phase balanced and unbalanced voltage sags. Requirements for certification and test reporting, including characterization of voltage-sag ride-through equipment are also defined.