IEEE C37.45-2007 pdf free.IEEE Standard Specifications for High-Voltage Distribution Class Enclosed Single-Pole Air Switches with Rated Voltages from 1 kV through 8.3 kV.
IEEE C37.45 establishes specifications for high-voltage (above 1000 V) distribution class enclosed single- pole air switches and associated accessories with rated voltages from 1 kV through 8.3 kV. All of these devices are intended for use on alternating current distribution systems. These specifications apply to the following specific types of equipment:
a) Distribution class enclosed single-pole air switches
b) Supports, mountings, fuse hooks, and tongs, all of the type used exclusively with distribution class enclosed single-pole air switches
c) Distribution class enclosed single-pole air switches used in enclosure packages
1.2 Background
In the headings and the text of this document there will be some areas where the information is included in brackets []. The information in the brackets is a term used in IEC standards that may be similar to the term used in this document, a term that is common in some parts of the world, or a term that has been used previously in IEEE or ANSI standards. Caution is advised when making comparisons.
2. Normative references
The following referenced documents arc indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments or corrigenda) applies.
3. General rating information
3.1 Ratings
The ratings of distribution enclosed air switches shall be applicable for the service conditions specified in 3.1.1 of IEEE Sid C37.40-20033. The ratings are validated as follows:
a) Rated maximum voltages, validated by the dielectric design tests specified in 4. 1.
b) Rated continuous current, validated by the temperature-risc design tests at the rated continuous current specified in 4.4.
c) Rated lightning impulse withstand voltage [basic impulse insulation level (BIL)], validated by the impulse withstand tests specified in 4.1.
d) Rated power frequency, as specified in 3.2.3.
e) Rated short-time currents, rated momentary withstand and rated 3 s withstand, validated by the design tests specified in 4.3.
1) The rated momentary short-time withstand current is the mis value of current, including the direct-current component that occurs in the first maximum offset current loop of the design tests specified in 4.3. The rated momentary current value for any device is based on its 3 s rated short-time withstand current multiplied by the appropriate asymmetry factor associated with the X/R specified. This rating provides an index of the ability of the device to withstand the electromagnetic forces that occur under maximum short-circuit conditions. To ensure that the device is tested with the proper severity, the first and second major current peaks shall be equal to or greater than those specified in IEEE Std C37.41-2000 Clause I 0 for the rated momentary current of the device.
2) The rated 3 s short-time withstand current test provides an index of the ability of the device to withstand the heat that may be generated under long-time short-circuit conditions.
3) The two tests in item 1) and item 2) can be combined as described in IEEE Std C37.41-2000. Clause 10.
It should be noted that for service conditions specified in 3.1.2 or 3.2 of IEEE Std C37.40-2003, additional testing to validate the rating of the device may be required.IEEE C37.45 pdf free download.