IEEE/ASA 21:1964

Revision Standard - Superseded.


This Standard covers the following: (1) Electrical requirements for outdoor power apparatus bushings having basic impulse insulation levels 110 through 1300 kilovolts. (2) Mechanical requirements for the outdoor power apparatus bushings listed in Table 7.4. (3) Dimensions of the outdoor power transformer and alternating-current power circuit breaker apparatus bushings listed in Tables 7.1(a), 7.1(b), and 7.1(c). 1.2 This Standard does not apply to bushings for indoor apparatus, dry type instrument transformers, air-blast transformers, dry type regulators, oil-less and oil-poor apparatus, roof, floor, wall and generator bushings, potherads, distribution type circuit breakers and back-connected switch insulators. 1.3 Bushing requirements as set forth in this Standard apply to bushings when mounted for testing, according to requirements outlined in Section 9.3.