In one aspect, the application provides an electrical system including a conductor, a ground, an arrester electrically connected to the conductor, and a disconnector assembly electrically connected between the arrester and the ground. The disconnector assembly includes an isolator configured to perform an operating function in response to the occurrence of an event and a housing configured to surround the isolator. The isolator includes a first terminal electrically connected to the arrester by a first wire and a second terminal electrically connected to the ground by a second wire. The housing includes a first opening through which the first terminal extends, a second opening through which the second terminal extends, and a retention mechanism configured to hold the isolator in place relative to the arrester.

Various implementations include a battery disconnect device that includes a breaker, a housing, and a bus bar. The breaker has a pivot portion and an actuation portion, and the actuation portion has an actuation face. The pivot portion has an axis of rotation about which the breaker is pivotable. The housing defines a chamber, and the chamber is in fluid communication with a gas generator via an inlet defined by an inlet wall of the housing. The breaker is disposed within the chamber in a first position in which the actuation face is adjacent the inlet and inlet wall and combustion gas from the gas generator pushes on the actuation face to cause the breaker to pivot about the axis of rotation of the pivot portion to a second position, which causes the breaker to break the bus bar.

A battery pack includes: a plurality of batteries including a first battery and a second battery; a first input/output port including a first input/output positive port and a first input/output negative port; a second input/output port including a second input/output positive port and a second input/output negative port; a first switch electrically connecting the positive terminal of the second battery to the negative terminal of the first battery or to the second input/output positive port; a second switch electrically connecting the negative terminal of the first battery to the first switch or to the first input/output negative port; and a third switch electrically connecting the negative terminal of the second battery to the first input/output negative port or electrically connecting the second switch to the first input/output negative port or to the second input/output negative port.

An embodiment of an arc flash reduction maintenance system includes a pyrotechnic disconnect module and an overcurrent protection device connected to the pyrotechnic disconnect module. A control line is connected to the at least one pyrotechnic disconnect module and in parallel with one of the pyrotechnic disconnect module and the overcurrent protection device. The control line provides a self-generating control signal to cause the pyrotechnic disconnect module to electrically isolate the overcurrent protection device. A switch is located in the control line to selectively enable or disable at least one arc flash reduction maintenance system mode in the control line.

An embodiment of an arc flash reduction maintenance system includes a pyrotechnic disconnect module and an overcurrent protection device connected to the pyrotechnic disconnect module. A control line is connected to the at least one pyrotechnic disconnect module and in parallel with one of the pyrotechnic disconnect module and the overcurrent protection device. The control line provides a self-generating control signal to cause the pyrotechnic disconnect module to electrically isolate the overcurrent protection device. A switch is located in the control line to selectively enable or disable at least one arc flash reduction maintenance system mode in the control line.

Systems for disconnecting a surge arrester. One embodiment provides a surge arrester comprising a housing, a connecting interface configured to connect to an electrical power grid, and a disconnector device coupled to the connecting interface. A metal oxide varistor stack is coupled to the disconnector device, and a ground side connection is coupled to the metal oxide varistor stack, the ground side connection configured to connect to a system ground. The disconnector device is configured to disconnect the connecting interface from the system ground based on a predetermined disconnection condition.

An active/passive fuse module including a base, a busbar disposed on a top surface of the base and including a fuse element and first and second terminal portions extending from opposite ends of the fuse element, the fuse element extending over a cavity in the top surface of the base, a pyrotechnic interrupter (PI) disposed atop the base, the PI including a piston disposed within a shaft above the fuse element, a first pyrotechnic ignitor coupled to a controller, the first pyrotechnic ignitor configured to detonate and force the piston through the fuse element upon receiving an initiation signal from the controller, and a second pyrotechnic ignitor coupled to the busbar by a pair of leads, the second pyrotechnic ignitor configured to detonate and force the piston through the fuse element upon an increase in voltage across the leads.

A direct current electric circuit interrupting switch assembly for establishing of electric connection comprising: a primary electric conductor and a secondary electric conductor integrated between a direct voltage electric source and at least one load; wherein said primary electric conductor of the switch assembly comprises two branches, which are in parallel connected with each other, of which the first branch includes an electric fuse with a melting member and the second branch includes a pyroswitch with an interrupting member, which is capable to interrupt said second branch of the primary electric conductor extending through said pyroswitch, as well as an actuator, which is capable to ensure appropriate movement of said interrupting member due to interruption of said second branch of the primary electric conductor; wherein said pyroswitch comprises such interrupting member, which is within said pyroswitch displaceable from a first position, in which by means of it said second branch of the primary electric conductor is uninterrupted and in which said interrupting member is held at a sufficient distance apart from the secondary electric conductor, into a second position, in which the electric circuit throughout the second branch of the primary electric conductor is interrupted and the interrupting member is held in an electric conductive contact with the secondary conductor of the switch assembly; wherein said switch assembly is furnished with an electric circuit, which includes a thermal electric fuse with a contact member as well as an electromagnetic switch, which is activated by exceeding of a pre-determined value of electric current, wherein said fuse and said switch are connected parallel with each other.

An alternatively changeable electric circuit comprising a voltage source, an electric load electrically connected with said electric voltage source via a basic electric conductor having a primary branch and a secondary branch, and an alternative conductor connected in parallel to said basic electric conductor, wherein upon fulfillment of a predetermined circumstance, said primary branch is physically interrupted, causing an electric current which initially flowed through said primary branch to be redirected through said alternative conductor. The alternative conductor comprises two electric conductive sections which are aligned with each other and spaced apart at a distance, forming an electrically insulating gap there-between. The primary branch includes an electrically conductive section, which upon the predetermined circumstance is removable from the primary branch and displaceable into said gap between said two electric conductive sections, causing the alternative conductor to become bridged and electrically conductive.

An alternatively changeable electric circuit comprising a voltage source, an electric load electrically connected with said electric voltage source via a basic electric conductor having a primary branch and a secondary branch, and an alternative conductor connected in parallel to said basic electric conductor, wherein upon fulfillment of a predetermined circumstance, said primary branch is physically interrupted, causing an electric current which initially flowed through said primary branch to be redirected through said alternative conductor. The alternative conductor comprises two electric conductive sections which are aligned with each other and spaced apart at a distance, forming an electrically insulating gap there-between. The primary branch includes an electrically conductive section, which upon the predetermined circumstance is removable from the primary branch and displaceable into said gap between said two electric conductive sections, causing the alternative conductor to become bridged and electrically conductive.