This invention relates to a circuit breaker and disconnect switch support member having means for attaching bolt-on electric circuit breakers such as described within U.S. Pat. No. 3,831,120 entitled "Trip Unit Having Improved Trip Adjustment Indicator and Circuit Breaker Incorporating Same". The so-called "bolt-on" circuit breakers cover a wide range of circuit breaker ampere ratings. Since the physical dimensions of the circuit breakers generally increase with increased circuit breaker ratings, the enclosure dimensions are customized to accommodate specific circuit breaker dimensions. Industrial electrical panelboards consequently must be fabricated and the circuit breakers installed at the factory site. One attempt to facilitate the accommodation of a wide range of molded case circuit breaker ratings is to attach a plastic base having plug-on jaws already attached thereto and bolting the circuit breakers directly to the base. The base is then installed within the custom panelboard by plugging the jaws directly onto the bus conductors located within the electric panelboard interior. Examples of such adapters are found in the following U.S. Pat. Nos. 3,354,357; 3,619,727; 3,787,712 and 3,842,322.
In order to facilitate on-site installation of electric panelboards, it is less time-consuming to order an electric panelboard from a supplier and directly connect the bolt-on circuit breakers at the construction site. The panelboard, accordingly, would have to accommodate a wide range of bolt-on type molded case circuit breakers without substantial modification of the panel-board interior. One purpose of the instant invention is to provide means for connecting such a wide range of circuit breakers within a panelboard interior at the site of intended use resulting in a substantial savings in both material costs and a substantial decrease in delivery time.