IEEE Standard Requirements for High- Voltage Switches

1. Overview 7

2. References 7

3. Definitions 8

4. Service conditions 8

4.1 Usual service conditions 8

4.2 Unusual service conditions 8

5. Ratings 9

5.1 Rated maximum voltage 9

5.2 Rated dielectric withstand voltages 9

5.3 Rated power frequency 9

5.4 Rated continuous current 9

5.5 Rated peak-withstand and short-time (symmetrical) withstand currents 11

5.6 Rated making current 12

5.7 Limit of corona and radio-influence voltage 12

5.8 Rated closing time (for power-operated switches) 12

5.9 Rated ice-breaking ability 13

5.10 Rated mechanical operations 13

5.11 Rated mechanical terminal load 13

5.12 Rated load-interrupting current 13

5.13 Ratings for switching shunt capacitance 13

5.14 Rated unloaded transformer interrupting current 14

5.15 Expected switching endurance 14

6. Test procedure 18

7. Nameplate markings 18

7.1 General 18

7.2 Interrupter switches 18

7.3 Fault-initiating switches 18

1. Overview

This standard applies to all high-voltage enclosed indoor or outdoor, and non-enclosed indoor or outdoor, switches rated in excess of 1000 V. This includes such switch types as disconnecting, selector, horn-gap, grounding, etc., for manual or power operation. The following switch types are not covered by this standard: distribution-enclosed, single- pole switches and distribution cutouts fitted with disconnecting blades; switches used in metal-enclosed gear covered by IEEE Std C37.20.2-1993, IEEE Std C37.20.3-1987, and IEEE Std C37.20.4-1996; and switches used in pad- mounted switchgear covered by IEEE Std C37.71-1984, ANSI C37.72-1987, and PC37.73 (Draft 8, Feb. 95).

NOTE — PC37.39, Proposed Standard for Interrupter Switches, is currently under development. Upon its approval and publication, all references to interrupter switches in this standard will be superseded.

This standard defines terms and words that uniquely apply to high-voltage switches and are not included in IEEE Std C37.100-1992. It also defines terms used for rating high-voltage switches and ratings that must be included on nameplates for high-voltage switches.

2. References

ANSI C37.32-1990, American National Standard for Switchgear—High-Voltage Air Switches, Bus Supports, and Switch Accessories—Schedules of Preferred Ratings, Manufacturing Specifications, and Application Guide.1

IEEE Std C37.34-1994, IEEE Standard Test Code for High-Voltage Air Switches (ANSI).2

IEEE Std C37.36b-1990 (Reaff 1996), IEEE Guide to Current Interruption with Horn-Gap Air Switches (ANSI).

IEEE Std C37.37-1996, IEEE Standard Loading Guide for AC High-Voltage Air Switches (in Excess of 1000 volts) (ANSI).

IEEE Std C37.100-1992 IEEE Standard Definitions for Power Switchgear.

IEEE Std 1-1986 (Reaff 1992) IEEE Standard General Principles for Temperature Limits in the Rating of Electric Equipment and for the Evaluation of Electrical Insulation (ANSI).

NEMA SG 6-1995, Power Switching Equipment.

Table 1— Switch ratings and required tests

*.Related to interrupter switches and will be superseded by IEEE PC37.39 when it is completed and approved.

†.Required if the interrupter switch has capacitance-switching ratings.

‡.At least one current-interrupting rating is required for interrupter switches.