Abstract: A circuit interruption device including first and second terminals for connection, to a respective electrical circuit or network, a current-conductive branch including first, second, and third current-conductive branch portions successively connected in series between the first and second terminals, the first current-conductive branch portion including a first switching element, the second current-conductive branch portion including a second switching element, the third current-conductive branch portion including a third switching element, each switching element configured to be switchable to selectively permit and block a flow of current in the respective current-conductive branch portion, first and second current bypass paths, the first current bypass path connected across the first and second current-conductive branch portions, the second current bypass path connected across the second and third current-conductive branch portions, and a controller configured to selectively control the switching of the swit

Abstract: A method is employed by a central controller of a radio communications system, which method provides for sustaining a predetermined level of communication service. The system includes a plurality of voice channels which are allocated among a plurality of subscribers (108-112) using a first control channel (102). In a preferred embodiment, at least one of the voice channels (104, 106) is also control-capable. The method includes evaluating (502) a current loading condition, and comparing (504) this loading condition with an upper loading threshold. Where appropriate, the controller assigns (506) one of the control-capable voice channels as a temporary control channel.

Abstract: A method (215) of converting a current control channel for use as a communication (voice/data) channel, in order to maintain a predetermined level of service in a radio communications system, employs a central controller (101) to allocate a limited number of communication channels among a plurality of subscriber units (108-112). After receiving (203) a request for a communication channel from one of a plurality of subscriber units (108-112), the controller (101) determines (205) whether all of the communication channels are busy. The controller then temporarily converts (215) the current control channel to a communication channel.