LV3.6.4 - 3.6.4 Surge Characterization on LV Circuits WG

Douglas Dorr

This guide applies to surge protective devices (SPDs) intended for connection to 50 Hz to 60 Hz ac power circuits rated 1000 V RMS or less. This guide describes the effects on SPDs of power system disturbances occurring in these low-voltage ac power circuits. The disturbances are not limited to surges. The effects of the presence and operation of SPDs on the quality of power available to the connected loads are described. The interaction among multiple SPDs on the same circuit is also described. This guide discusses both voltage and current surges. The current surges discussed in this guide are the result of voltage surges. Current surges that are solely the result of load changes and do not result in voltage increases, such as a short circuit, are not discussed in this guide. An SPD's primary purpose is to provide surge protection. Devices discussed in this guide contain at least one nonlinear component for diverting surge current and/or dissipating surge energy, such as a metal oxide varistor (MOV), silicon avalanche diode (SAD), thyristor, or spark gap. Uninterruptible power supplies (UPSs), ferroresonators, motor-generators, and filters containing only inductive and/or capacitive components are not considered SPDs in this guide.

This is a guide describing the surge voltage, surge current, and temporary overvoltage (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 surges 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. 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 the purpose clause.

The scope of this recommended practice is to characterize the surge environment at locations on ac power circuits described in IEEE Std C62.41.1 by means of standardized waveforms and other stress parameters. The surges considered in this recommended practice do not exceed one half-cycle 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. While surge protective devices (SPDs) acting primarily on the amplitude of the voltage or current are often applied to divert the damaging surges, the upsetting surges might require other remedies.

This recommended practice defines recommendations for surge testing performance of surge testing on electrical and electronic equipment connected to low-voltage ac power circuits, specifically using the recommended test waveforms defined in IEEE Std C62.41.2. Nevertheless, these recommendations are applicable to any surge testing, regardless of the specific surges that may be applied.

A practical basis is provided for the selection of voltage and current tests to be applied in evaluating the surge withstand capability of equipment connected to utility power circuits, primarily in residential, commercial, and light industrial applications. The recommended practice covers the origin of surge voltages, rate of occurrence and voltage levels in unprotected circuits, waveshapes of representative surge voltages, energy, and source and impedance. Three locations categories are defined according to their relative position from the building service entrance. For each category, representative waveforms of surge voltages and surge currents are described, organized in two recommended ?standard waveforms? and three suggested ?additional waveforms.?

A practical basis is provided for the selection of voltage and current tests to be applied in evaluating the surge withstand capability of equipment connected to utility power circuits, primarily in residential, commercial, and light industrial applications. The recommended practice covers the origin of surge voltages, rate of occurrence and voltage levels in unprotected circuits, waveshapes of representative surge voltages, energy and source and impedance. Three locations categories are defined according to their relative position from the building service entrance. For each category, representative waveforms of surge voltages and surge currents are described, organized in two recommended standard waveforms and three suggested additional waveforms.

This IEEE standards product is part C62 Family on Surge Protection and supersedes C62.41 The scope of this recommended practice is to characterize the surge environment at locations on ac power circuits described in IEEE Std C62.41.1-2002 by means of standardized waveforms and other stress parameters. The surges considered in this recommended practice do not exceed one half-cycle 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. While surge protective devices (SPDs) acting primarily on the amplitude of the voltage or current are often applied to divert the damaging surges, the upsetting surges might require other remedies.

Guidance is provided for applying surge testing to AC power interfaces of equipment connected to low-voltage ac power circuits that are subject to transient overvoltages. Signal and data lines are not addressed in this document, nor are any specifications stated on the withstand levels that might be assigned to specific equipments. An important objective of the document is to call attention to the safety aspects of surge testing.

Superseded by C62.45-2002. Guidance is provided for applying surge testing to ac power interfaces of equipment connected to low-voltage ac power circuits that are subject to transient overvoltages. Signal and data lines are not addressed in this document, nor are any specifications stated on the withstand levels that might be assigned to specific equipments. An important objective of the document is to call attention to the safety aspects of surge testing.

Information is provided to users and manufacturers of surge-protective devices(SPDs) about the interactions that may occur between SPDs and power system disturbances. This guide applies to SPDs manufactured to be connected to 50 or 60 Hz ac power circuits rated at 100-1000 V rms. The effects and side effects of the presence and operation of SPDs on the quality of power available to the connected loads are described. The interaction between multiple SPDs on the same circuit is also described.

Information is provided to users and manufacturers of surge-protective devices (SPDs) about the interactions that can occur between SPDs and power system disturbances. This guide applies to SPDs manufactured to be connected to 50 or 60 Hz ac power circuits rated at 100-1000 V RMS. The effects of the presence and operation of SPDs on the quality of power available to the connected loads are described. The interaction between multiple SPDs on the same circuit is also described.

The scope of this recommended practice is the performance of surge testing on electrical and electronic equipment connected to low-voltage ac power circuits, specifically using theree commended test waveforms defined in IEEE Std C62.41.2TM-2002. Nevertheless, these recommendations are applicable to any surge testing, regardless of the specific surges that may be applied. This IEEE standards product is part C62 Family on Surge Protection.

Deletion of Table A.2 and associated text is addressed in this corrigendum.