Abstract: A molded case circuit breaker support and a circuit breaker enclosure are arranged with air transfer slots and passages to promote chimney effect cooling of the circuit breaker components. The slots in the circuit breaker support direct ambient cooling air onto the circuit breaker terminals while the passages through the enclosure direct the ambient air flow from the bottom to the top of the enclosure.

Abstract: A combination panelboard-switchboard housing accepts plug-on connection with a plurality of electric switch-circuit breaker modules. Circuit breakers can also be directly connected onto the bus bars in a plug-on connection with minor modification. The bus bars are "edge-mounted" such that the minor dimension of the bus bars is perpendicular to the bottom of the housing to receive the modules as well as the circuit breakers, per se. Electrical insulation shields are arranged over those bus bars that are not connected with the circuit breakers or modules to prevent inadvertent contact with the bus bars when energized. The tabs extending from the edge of the insulation shields are keyed to accommodate for the different widths of the modules when the insulation shields are flush-mounted against one side of the modules.

Abstract: A combination panelboard-switchboard housing accepts plug-on connection with a plurality of electric switch-circuit breaker modules. Circuit breakers can also be directly connected into the bus bars in a plug-on connection with minor modification. The bus bars are "edge-mounted" such that the minor dimension of the bus bars is perpendicular to the bottom of the housing to receive the modules as well as the circuit breakers, per se. Plastic or fiber insulation shields are arranged over those bus bars that are not connected with the circuit breakers or modules to prevent inadvertent contact with the bus bars when energized.

Abstract: A multi-component electric switch-circuit breaker module permits electric switches and circuit breakers to be field-installed within existing panelboard-switchboard enclosures. The module contains a pair of compartments that are accessed by separate doors. Electric switches or circuit breakers can be arranged within both compartments or an electric switch can be installed within one compartment with an electric circuit breaker installed within the other. The module is removably attached to the panelboard-switchboard interior by means of a bail handle arrangement. The module is removed from the assembly by unscrewing the bail handle and manually accessing the module. Spring-loaded connector clips allow for repeated connection with and disconnection from the systems power bus with minimum contact resistance.