IEEE C62.41-1991 (R1995) pdf free.IEEE Recommended Practice on Surge Voltages in Low-Voltage AC Power Circuits.
IEEE C62.41 Specific equipment sensitivities should be defined in concert with the above-mentioned goals. The sensitivities will bedifferent for hardware failure or process upset.Such definitions might include: maximum surge remnant amplitudeand duration that can be tolerated, waveform or energy sensitivity, etc.
The applicable test waveforms recommended in this document should be quantified on the basis of the locationcategories and exposure levels defined herein.
The magnitude of the rms power-line voltage, including any anticipated variation, should be quantified.Power systemvoltages are generally regulated to comply with ANSI C84.1-1989 [1].That standard specifies two ranges (A and B)of service and utilization voltages and explicitly acknowledges the occurrence of abnormal conditions that cause thesevoltages to be exceeded.Successful application of surge-protective devices requires taking into consideration theseoccasional abnormal occurrences.Appropriate selection of the clamping voltage and continuous mains voltage ratingsis essential.
Evaluation of a surge-protective device should verify a long life in the presence of both the surge and electrical systemenvironments described above. At the same time, its remnant and voltage levels should provide a margin from thesensitivity levels of the equipment to achieve the desired protection. It is essential to consider all of these parameterssimultaneously.For example, the use of a protective device rated very close to the nominal system voltage may provideattractive remnant figures, but may be unacceptable when a broad range of occasional abnormal deviations in theamplitude of the mains waveform are considered. Lifetime or overall performance of the surge-protective deviceshould not be sacrificed for the sake of a low remnant (Martzloff and Leedy,1989[B46]).
The surge test environment should be carefully engineered with regard to the preceding considerations and any otherparameters felt important by the user. A typical test-environment description will include definitions of simultaneousvoltages and currents， along with demonstrations of proper short-circuit currents. It is important to recognize thatspecification of an open-circuit voltage without simultaneous short-circuit current capability is meaningless.IEEE C62.41 pdf download.