This is a guide describing the surge voltage, surge current, and TOV environment in low-voltage [up to 1000 V root mean square (rms)] ac power circuits. This scope does not include other power disturbances, such as notches, sags, and noise. The surge considered in this guide do not exceed one-half period of the normal mains waveform (fundamental frequency) in duration. They can be periodic or random events and can appear in any combination of line, neutral, or grounding conductors. They include surges with amplitudes, durations, or rates of change sufficient to cause equipment damage or operational upset (see Figure ). While surge protective devices (SPDs) acting primarily on the amplitude of the voltage are often applied to divert the damaging surges, the upsetting surges may require other remedies. The rationale for including a description of TOVs in this guide on the surge environment is given in .
This guide, the first of a Trilogy of three IEEE standards addressing surges in low-voltage ac power circuits, focuses on the surge environment and on the TOV environment. This part provides readers with basic information on the occurrence of surges, as a database for the second document of the Trilogy, IEEE Std C62.41.2-2002 where recommendations are presented on the selection of representative surge parameters to be considered in assessing equipment immunity and performance of SPDs. The third document of the Trilogy, IEEE Std C62.45-2002 , presents recommendations on surge testing procedures for obtaining reliable measurements and enhancing operator safety. Including a description of TOVs in a document that has surges as its principal topic is necessary for the following reason:Correct application of SPDs--a topic not addressed directly in this Trilogy--does require knowledge of the TOVs to which these SPDs will be exposed to ensure compatibility of the SPDs with the TOV-related stresses. Thus, this information will serve as an input for other documents addressing the application of SPDs in the environment of low-voltage ac power systems.
New IEEE Standard - Inactive-Reserved.
This is a guide describing the surge voltage, surge current, and temporary overvoltages(TOV) environment in low-voltage [up to 1000 V root mean square (rms)] ac power circuits. This scope does not include other power disturbances, such as notches, sags, and noise. This IEEE standards product is part C62 Family on Surge Protection.