TABLE OF CONTENTS With the advent of direct-off-line switchmode power supplies using sensitive electronic primary control circuits, the need for input AC powerline transient surge protection has become more universally recognized.
Measurements carried out by the IEEE over a number of years have demonstrated, on a statistical basis, the likely frequency of occurrence, typical amplitudes, and waveshapes to be expected in various locations as a result of artificial and naturally occurring electrical phenomena. These flndings are published in IEEE Standard 587 1980 [*] and are shown in Table 1.2.1. This work provides a basis for the design of AC powerline transient surge protection devices.40
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| *For high-impedance test specimens or load circuits, the voltage shown represents the surge voltage. In making simulation tests, use that value for the open-circuit voltage of the test generator. For low-impedance test specimens or load circuits, the current shown represents the discharge current of the surge (not the short-circuit current of the power system). In making simulation tests, use that current for the short-circuit current of the test generator. Other suppressors which have different clamping voltages would recieve different energy levels. |
[*] Also issued under ANSI/IEEE Standard C64.41 1980 and IEC Publication 664 1980.
In general terms, the surge stress to be expected depends on the location of the equipment to be protected. When equipment is inside a building, the stress depends...
