Abstract:
A fault interrupting and reclosing device includes a circuit interrupter coupled to an actuator. The actuator includes at least one force generating element for generating an opening force for opening the circuit interrupter and for generating a restoring force to close the circuit interrupter. The device further includes a latch to engage the actuator to hold the contacts open once opened. In a preferred arrangement, the device is provided with an automatic mode of operation including a reclose process and a non-reclosing mode of operation. The device also preferably includes a method of determining the end-of-life of a vacuum interrupter monitors characteristics and/or parameters of a fault current or vacuum interrupter operation to predict a percent of life consumed with each fault current interruption operation. A cumulative percent of life consumed may also be determined, and an end-of-life may be predicted based upon the cumulative percent of life consumed.
Abstract:
A rotating arc fault-current interrupter, also known as an arc spinner interrupter, is provided that establishes an easily visible open gap via a movable blade member having a first portion for engaging a stationary main contact and a second portion formed by an arcing electrode for engaging an auxiliary contact associated with an arc spinner assembly. The geometry, orientation and placement of the auxiliary contact is such that during opening of the movable blade member, the arcing electrode remains engaged with the auxiliary contact after the blade member and the stationary main contact are separated from each other whereby current is transferred through the auxiliary contact into the arc spinner assembly, i.e. the current is commutated into the arc spinner assembly. Thus, the current in the arc spinner creates a magnetic field to cause the arcing current to rotate rapidly so as to extinguish the arc as the arcing electrode separates from the auxiliary contact and moves to the opened position whereby a visible open gap is established that is easily visible without any obstructions from a range of viewing angles or orientations.
Abstract:
A voltage sensing apparatus includes an output for a voltage tap point that is useful in representing the voltage on a conductor that passes through the voltage sensing apparatus. The voltage sensing apparatus also performs the function of a separable insulated conductor, e.g. a conventional bushing or bushing insert as utilized in the electrical power distribution field. The voltage sensing apparatus includes a molded body having an embedded capacitance screen that provides the output. The body is molded about the capacitance screen. An arrangement is provided for locating the capacitance screen within the molded body. In a preferred embodiment, the capacitance screen is molded from a conductive plastic preferably formed with an open mesh or screen structure that permits the free flow of molding material.
Abstract:
A low-exhaust composite drop-out assembly is provided that is utilizable in a standard cutout mounting in electrical power distribution systems. The composite drop-out assembly includes current-limiting and low-current clearing sections and is easily removable from the mounting for servicing. The sections are efficiently arranged in a side by side configuration. The low-current clearing section includes a fuse-tube assembly having a replaceable fuse cartridge. Accordingly, the low-current clearing section is simply and economically renewable for reuse whether or not the current-limiting section has operated. Further, the current-limiting section need not be replaced if only the low-current clearing section operated in response to overcurrent in a low range. Additionally, the sections are separable so that the low-current clearing section can be reused after simple refusing even when the current-limiting section has operated.
Abstract:
An exhaust-control device is provided to absorb the energy of exhaust gases released during operation of a circuit-interrupting device such as a power fuse or an expulsion fuse. The exhaust-control device includes a first heat-absorbing medium through which the exhaust gases pass for reducing the temperature of the exhaust gases below a predetermined temperature. The exhaust-control device further includes a second heat-absorbing medium for receiving the exhaust gases exiting from the first heat-absorbing medium. The material, quantity, size distribution, and arrangement of the first heat-absorbing medium is selected so that the predetermined temperature of the exhaust gases does not cause significant melting of the second heat-absorbing medium that is utilized. In a specific arrangement, the first heat-absorbing medium is a section of ceramic pellets and the second heat-absorbing medium is a roll of woven copper mesh.
Abstract:
An energy-absorbing element is provided between an insulative piston and a movable contact of a switch for a high-voltage device. In arrangements where a fusible element is in electrical shunt with the switch, the energy-absorbing element improves the rapid commutation of the current from the switch to the fusible element where final circuit interruption takes place. The switch is of the general type in which ignition of a power cartridge moves the insulative piston, which is normally located in a bore formed in a conductive member, away therefrom and into a passageway formed in an insulative liner. The movement of the piston moves the movable contact through the passageway and away from the conductive member to break an electrical interconnection between the conductive member and the movable contact. This forms a gap between the conductive member and the movable contact and opens the switch. The ignition of the power cartridge evolves high pressure within a chamber defined by the piston and the bore. This high pressure acts against the piston and the resulting forces rapidly drive the piston; the movable contact being driven via the transmission of forces through the energy-absorbing element. The energy-absorbing element enhances the rapid and simultaneous movement of the piston and the movable contact. The energy-absorbing element absorbs sufficient energy at the interface between the piston and the movable contact to prevent undesirable reaction effects which may be caused by the reaction or rebounding forces between the piston and the movable contact.
Abstract:
An improved switch for a high-voltage device in which ignition of a power cartridge generates pressure at one end of an insulative piston to move the piston, located in a conductive member, into a passageway in an insulative liner, said piston moving a contact through the passageway and away from the conductive member to break an electrical interconnection between the conductive member and the movable contact,an insulative lip seal located in the bore between the power cartridge and the one end of the piston, the lip seal being movable with the piston and being conformally force-fit into the bore, andmeans limiting movement of the lip seal through the bore so that the lip seal remains in the bore after the switch is open restricting the flow of the ignition products of the power cartridge.
Abstract:
Disclosed in a high voltage switch operating mechanism which utilizes energy stored in a spiral spring to drive the high voltage switches from either the open to the closed or the closed to the open position. The spring can be charged either by a manual tool or by an electric motor. The switch can be tripped by either electric or manual trip mechanisms. Manual and electric trip interlock assemblies are provided to prevent the switch operating mechanism from being tripped either manually or electrically while the spring is being charged. A mechanism is provided to prevent the charging of the spring by the electric motor when the manual tool is used to charge the spring. Another mechanism is provided to decouple the operating mechanism from the switch. To allow testing of the operating mechanism without change of the switch state. The decoupling mechanism locks the switch to its present position before the decoupling is complete allowing the energy in the operating spring to be dissipated.
Abstract:
A bounce- and weld- resistant contact assembly includes a pair of spaced contact plates with facing contacts on their ends. A switch blade is rapidly movable into and out of engagement with the contacts. The contacts are convexities coined into the plates which add no mass to the plates. Thus, the natural frequency of the plates is maximized and the magnitude of oscillation of the plates, when the contacts are rapidly engaged by the blade, is minimized. Legs on leaf springs act against concavities formed in the plates opposite the convexities. The legs conformally nestle in the convexities so that their frictional engagement therewith and the spring force co-act to quickly damp the high frequency, low magnitude oscillations of the plates. The low mass coined contacts also permit close spacing of the plates to maximize magnetic forces thereon due to current flow therethrough. These forces aid the spring and the leg-concavity friction in quickly damping oscillations of the plates.