In this white paper methods for determining sources of voltage sag are discussed, as well as some example files that have identifiable sources of voltage sag. When placing a recorder to identify a specific problem, it is necessary to have the settings altered to capture the parameters needed to find the source. In order to capture and identify voltage sag causes, we must first consider the recorder settings. The most useful parameters in identifying such issues are the Voltage and Current intervals, single cycle histograms, and waveform captures. It is HIGHLY recommended to always record current in every recording session. The high emphasis on the current measurement is necessary because the voltage recording alone is basically useless in identifying the cause of an issue. The current signature is representative of customer load and can be used to differentiate between customer load issues and power sourcing issues. Discussed below are examples of Voltage Sag issues and the settings used to capture them.
This white paper includes: