Abstract: A switchboard for mounting and supplying electrical power to a plurality of circuit breakers. The switchboard comprises a frame including a center mounting pan, and at least first and second circuit breaker mounting pans for engaging and supporting the rear end portions of the circuit breakers. The switchboard also comprises a power stack assembly mounted on the center mounting pan of the frame. The power stack assembly includes first, second and third, substantially vertically disposed main bus bar members for being connected to a source of electrical power and for releasably engaging the circuit breakers. The first main bus bar member is selectively spaced from the center mounting pan with insulator members so as to define a first ventilation passageway therebetween. The second main bus bar member is selectively spaced from the first main bus bar member with insulator members so as to define a second ventilation passageway therebetween.

Abstract: A clamping assembly which provides a uniform pressure simultaneously at two spaced apart points. The assembly includes a portion of a support member which has two parallel sides and a passage connecting the two parallel sides. A tubular shaped sleeve is received within the passage and includes short tabs extending slightly past the surface of the two parallel sides of the support member. A U-shaped anti-turn bracket is slidably received around the support member and includes slots that coincide with the passage in the support member. The tubular sleeve has a non-circular inside cross-section. A double-ended bolt having a first and second threaded end and an intermediate non-circular portion complementary to the non-circular cross-section of the sleeve is slidably received within the sleeve. The bolt is permitted to move linearly but not permitted to rotate within the sleeve. Threaded nuts are placed on each of the first and second threaded end.