IEEE C62.11a-2008 pdf free.IEEE Standard for Metal-Oxide Surge Arresters for AC Power Circuits (>1 kV) Amendment 1: Short-Circuit Tests for Station, Intermediate, and Distribution Arresters.
All station, intermediate, and distribution arresters shall be tested in accordance with this subclause. The test shall be performed in order to show that an arrester failure does not result in a violent shattering of the arrester housing. by testing each arrester type with two or more values of short-circuit currents. If the arrester is equipped with some other arrangement as a substitute for a conventional pressure relief device, this arrangement shall be included in the test.
The frequency of the short-circuit test current supply shall be no less than 48 Hz and no more than 62 Hz.
With respect to the short-circuit current performance it is important to distinguish between 2 types of arresters as follows:
— “Design A” arresters have a design in which a gas channel runs along the entire length of the arrester unit and tills  50 % of the internal volume not occupied by the internal active parts. Typically, “Design A” arresters are porcelain housed arresters, or polymer housed arresters with a composite hollow insulator which are equipped either with pressure relief devices, or with prefabricated weak spots in the composite housing. If the valve elements fail electrically, an arc is established within the arrester. This arc causes an increase in pressure inside the housing, which will burst or flip open the pressure relief devices or prefabricated weak spots, thereby decreasing the internal pressure.
— “Design B” arresters are of a solid design with no enclosed volume of gas or having an internal gas volume filling < 50 % of the internal volume not occupied by the internal active parts. Typically, “Design B” arresters do not have any pressure relief device and are of a solid type with no enclosed volume of gas. If the valve elements fail electrically, an arc is established within the arrester. This arc causes heavy evaporation and possibly burning of the housing andior internal material. These arresters’ short circuit performance is determined by their ability to control the cracking or tearing open of the housing due to the arc effects, thereby avoiding violent shattering.
NOTE— “Active parts” in this context are the non-linear metal-oxide valve elements and any metal spacers directly in series with them.
Depending on the type of arrester and test voltage, different requirements apply with regard to number of test samples. initiation of short-circuit current, and amplitude of the first short-circuit current peak. Table Am 1. shows a summary of these requirements, which arc further explained in the following subclauses.IEEE C62.11a pdf download.