Abstract: A circuit breaker/surge arrestor package for plug-in installation in the space of two standard one-inch openings in a contemporary residential load center. The electrical and thermal characteristics of the components are selected such that a threshold of a substantially continuous current through a Metal Oxide Varistor in the surge arrestor causes the circuit breaker to trip magnetically before being able to trip thermally.

Abstract: Fault gas seals to prevent the ejection of a surge arrester from a loadbreak bushing due to the generation of such gas in response to the failure of arrester devices in such surge arrester. A metal O-ring support is bonded to the conductive insert of the arrester housing or added as a retrofit to such housing. Annular grooves in the loadbreak probe are fitted with O-rings which are compressed against the support to provide a gas-tight passage along the probe surface. An additional annular groove can be used to receive a fastener to hold the retrofit in position.

Abstract: A weatherproof station protector module for communication systems includes a hollow housing on which is disposed a pair of weatherproof line terminals that extend into the hollow housing and a ground terminal. A holding assembly is affixed to the ground terminal within the hollow housing and is adapted to receive a surge arrester therein. The surge arrester may be a three terminal device or a pair of two terminal arresters with one electrode of each connected to the ground terminal and each one of the other electrodes being connected to a line terminal.

Abstract: This lightning arrester includes (i) a tubular housing comprising a plurality of tubular sections disposed in telescoping aligned relationship to define an internal chamber and (ii) a stack of arrester elements located within this chamber. Locking means between adjacent telescoping sections holds the sections together in aligned relationship.Each locking means between adjacent sections comprises radially-projecting lugs on a telescoping portion of one of the sections and generally L-shaped slots in a telescoping portion of the other of the sections. The lugs fit into the slots and are displaced into locking portions of the slots by twisting motion of one of the adjacent sections relative to the other.In one embodiment, the housing sections are molded components of polymeric material and the lugs are also of polymeric material and are integral portions of the tubular housing on which the lugs are located.

Abstract: This surge voltage arrester has two connecting fittings (1, 2) which are braced with respect to one another. At least one pellet (7) consisting of varistor material is clamped in between the connecting fittings (1, 2).It is intended to create a surge voltage arrester which can be produced using simple means and which, in addition, can be cast around in a simple manner. This is achieved in that at least two insulating clamping elements, which are arranged symmetrically, are provided for bracing the connecting fittings (1, 2). The clamping elements, the at least one pellet (7) and, partially, the connecting fittings (1, 2) have insulating plastic material cast around them to form a monolithic block.

Abstract: A thin flexible laminate for overlay application on the pins of a connector or other circuit element, having an electrically insulating substrate, a conductive lamina of apertured pin receiving pads and a separate ground strip adjacent the pads, and an electrically insulating cover lamina, the substrate and cover having apertures aligned with the pad apertures, the cover having second apertures exposing adjacent edges of said pads and ground strip, with an electrical overstress pulse responsive composite material positioned in the second apertures and bridging the pads and the ground strip.

Abstract: A material and device for electronic circuitry that provides protection from fast transient over-voltage pulses. Conductive particles are dispersed in an insulating matrix to provide material having foldback switching characteristics. The foldback switching characteristics of the material are determined by the spacing between the conductive particles (which must be at least 1000 Angstroms) as well as by the electrical properties of the insulating matrix.

Abstract: A varistor and resistor device for incorporating in the interrupting chamber of a dielectric gas circuit breaker, the varistor and resistor components being connected in series and being housed in an insulating tube. The varistor components and the resistor components are firstly superposed with superposed components being separated from one another by insulating components, and are secondly juxtaposed with juxtaposed components being electrically interconnected by conductor components interposed between the ends of the superposed components and the insulating components.

Abstract: A high voltage surge arrester includes first, second and third terminals. Arrester components, including one or more arrester valve blocks, are serially disposed in an insulating arrester housing between the first and second terminals. A first current carrying conductor is connected between the second and third terminals by way of a disconnector. If the arrester fails, the disconnector will disengage the first current carrying conductor to provide a visible indication that the arrester has failed. At the same time, a second current carrying conductor then reestablishes the connection between the second and third terminals. Thus, a current carrying conductive path is maintained between the first and third terminals.

Abstract: A surge protection system has a surge protection device comprising a semiconducting disc element disposed between two electrodes. The element is operable to selectively conduct electrical energy between the electrodes in providing a first level of surge protection for the circuit, and the electrodes are adapted to move toward each other to maintain a short circuit condition between the electrodes in the event the element is destroyed in providing a second relatively greater level of surge protection. The semiconducting element provides a critical energy conduction path between a selected limited portion of one side of the element and the other element side along which destruction of the element preferentially occurs due to overheating in providing the second level of surge protection.

Abstract: A miniature solid state surge protector apparatus for use in telephone central offices, or the like, that are provided with terminal blocks for communication lines which may include an in-line overcurrent coil arrangement that grounds each communication line if an overcurrent flows therethrough and is additionally provided with a solid state miniaturized surge protection device disposed across a pair of communication lines and a common ground terminal, thus providing overvoltage and overcurrent protection (fail short) to a pair of telephone communication lines.

Abstract: A railway track circuit surge suppression system for the protection of wayside equipment from transitory energy surges appearing in the rails. The system has a primary surge suppression stage typically near the rails and a secondary surge suppression stage typically near the equipment to be protected. The secondary stage comprises an apparatus having a pair of inductors arranged serially with the respective track line wires to oppose the flow of surging current. Thus, the much of the energy dissipates at the primary stage. Remaining energy is dissipated by a voltage clamp behind the inductors.

Abstract: A high voltage surge arrester comprise plurality of low voltage surge arresters coupled together in a series parallel network, the low voltage arresters being of a high strength polymeric type consisting of a solid core of varistor blocks encased within a glass fibre reinforced plastics shell and housed in a shedded polymeric housing, and the series parallel network consisting of a plurality of series connected stages each of which comprises a generally annular mounting plate formed with an integral corona discharge suppression ring and a plurality of the low voltage surge arresters mounted to the mounting plate at uniformly spaced apart positions. The subject high voltage, series parallel surge arrester can replace conventional station class porcelain housed surge arresters, which are expensive, troublesome to transport and instal and liable to electrical problems, and avoids all of these problems whilst providing numerous significant advantages.

Abstract: An arresting insulator is provided which includes an insulator body made of an insulative material and a non-linear resistor. The insulator body includes a head for linking the insulator to an adjacent insulator, and a shed formed integrally with the head. The resistor is secured in the insulator body and has a non-linear relation between residual voltage and current. More specifically, the resistor has a characteristic that satisfies the equation:V.sub.NmA /H.gtoreq.300 V/mmwherein V.sub.NmA is a threshold reference voltage that causes a current of at least N milliamps to start flowing across the resistor to cause the resistor to perform a surge absorbing function. N is an arbitrary value in the range of 1 to 10, and H is the axial length of the resistor along a direction of electric field in millimeters.

Abstract: An electrical assembly, such as an insulator or a surge arrester, utilizing a pair of end collars for coupling an elastomeric weathershed housing to a pair of metallic end fittings, and for reducing electrical stress at the interface of the ends of the weathershed housing and the end fittings, and for sealing the ends of the weathershed housing to the end fittings. In particular, a radially directed force is applied to the weathershed housing by insertion of the core member into the axial bore of the weathershed housing causing radial outward expansion of the weathershed housing into intimate contact with the end collars. Also, each of the ends of the weathershed housing is held in contact against the inner end of the respective end fitting to seal the interface therebetween. Accordingly, a watertight seal is created at the interface between each of the end fittings and the ends of the weathershed housings.

Abstract: An electric protective device for protecting a cable, its termination or other apparatus from the effect of lightning strikes on an overhead line to which the apparatus is connected comprises a tubular insulator combined with a surge arrester and integrated by common terminals at the ground and high voltage ends. The insulator and the surge arrester are concentrically disposed about the conductor in a common insulated structure to eliminate connecting leads therebetween and the voltage drop which occurs across such leads during a rapid rise in current. The surge arrester may contribute all or part of the electrical stress grading required in the termination.

Abstract: A telephone line overcurrent protector adapted to be mounted on a circuit board is shown having a cup shaped housing in which a PTC element is placed with leads extending out of the housing through apertures in a bottom cover. The bottom cover is formed in one embodiment with a frangible diaphragm to provide guided pressure release upon catastrophic failure of the PTC element, in another embodiment with open apertures in the bottom cover and in yet another embodiment with means to mount a snap out member closing an aperture in the bottom cover, both for the same purpose of providing guided pressure release.

Abstract: A lightning surge protector, comprises a current limiting element in a pressure-proof housing. The pressure-proof housing is composed of a conductive material and coupled with an upper electrode member. Also, a self arc-extinguishing LSP comprises a current limiting element and upper and lower electrode members housed and fixed in a conductive pressure-proof housing opened at its lower portion through a suspension structure composed of a suspension rod. The outside and inside of the housing are covered and filled with an insulator, so that, upon occurrence of an internal arc due to a short-circuit fault or the like, the energy due to the arc causes the lower electrode member to break the insulator in the vicinity of an opening portion of the conductive pressure-proof housing so as to electrically connect the conductive pressure-proof housing to a part of the lower electrode member.

Abstract: Disclosed is a device which includes a Maintenance Termination Unit (MTU) and surge protector in a single 5-pin package. In accordance with one embodiment, a base includes an array of spring contacts, including a grounding element, in which are inserted both a surge protector module and an edge of a circuit board including the MTU.

Abstract: A line protector for a communications circuit comprises a generally cup-shaped housing; and a generally disc-shaped solid state overvoltage arrester having electrodes formed at axially oppositely facing surfaces thereof for connection to a line circuit and a ground circuit respectively. An elongate contactor extends into the housing for contacting a first one of the electrodes and projects outwardly of the housing for contacting one of the line circuit and the ground circuit. An insulator member receives and positions the solid state overvoltage arrester with the other of the electrodes thereof in contact with a closed end of the cup-shaped housing and with the first electrode in position for contacting the contactor. An elastomeric member surroundingly engages the contactor and is surroundingly engaged by the cup-like housing for retaining the contactor, the insulator member and the overvoltage arrester in asembled condition within the housing.

Abstract: A voltage limiter arrangement, including a voltage limiter including a central connecting lead and outer connecting leads positioned on each side of the central connecting lead. A surge arrester magazine is provided including a surge arrester magazine housing and contacts for connection to leads of the voltage limiter. The surge arrester magazine is provided with an open upper end. A receiving member is provided including a receiving opening for accommodating the voltage limiter, the receiving opening including a bottom wall with openings for each of the central connecting lead and the outer connecting leads. The receiving member includes guide elements for guided insertion of the receiving member into the open end of the arrester magazine for guided connection of the central connected lead and the outer connecting leads with contacts of the surge arrester magazine. The surge arrester magazine open upper end preferably includes an inner wall contour corresponding to the guide means of the receiving member.

Abstract: A distribution class surge arrester comprises a core formed of distributed zinc oxide varistor blocks, aluminum blocks acting as heat sinks and as spacers providing voltage grading and required arcing distances, and terminal blocks held in face-to-face contact by means of a glass reinforced epoxy shell which is formed by winding a pre-preg onto the assembled blocks and thermally curing under mold pressure within an evacuated mold. The core is housed within a polymeric shedded housing which is formed by shrinking a heat-shrink shedded sleeve onto the core with a sealant provided in the interface of the core and the sleeve, and end caps are sealed to the ends of the structure thus formed.

Abstract: An apparatus for protecting electrical installations against transients includes one or more devices comprising a network of varistors connected through a gas discharge tube to live, earth and neutral conductors. The varistors each have a terminal connected to an associated pole of the tube and the other terminal to the associated conductor. The apparatus may have three devices connected in cascade and preferably, inductances connected in series in the live and neutral conductors between the devices and the load. Preferably, varistors interconnect the conductors between the inductances and load. Relatively cheap and efficient apparatus for discharging transient over-voltages is provided.

Abstract: A fail-safe device is provided for a thyristor where the thryistor has a body member with extending tip, ring and ground leads. The fail-safe device includes an electrically conductive spring member having first, second and third contact ends. The spring member is sized to be fitted over the thyristor body with the first contact end opposing the tip lead, the second contact end opposing the ring lead and the third contact end opposing the ground lead. A dielectric spacer is provided disposed to space the first and second contact ends from the tip and ring leads. The spacer means is formed from a material selected to deform under a force of the bias of the spring at an elevated temperature generated in response to the thyristor failing to ground the tip or ring leads during an overvoltage condition.

Abstract: In a varistor of generally cylindrical configuration, which may serve as a connector pin, layers of ceramic material are interleaved between layers of electrode material, each ceramic layer being sandwiched between two electrode material layers. Each layer of electrode material is generally planar and extends transversely to the axis of the cylindrical varistor, in the form of an annular ring. Each alternate annular ring is of different inner and outer diameter. The outer periphery of each larger diameter annular ring is in electrical contact with an outer terminal cap of the varistor, while the inner periphery of each smaller diameter annular electrode layer is in electrical contact with an inner terminal cap extending along a central bore passing axially through the varistor pin. Each ceramic layer may have a thickness dimension less than 30.0 microns, or may be formed by deposition of a powder suspension and subsequent heat treatment to provide a dense continuum of ceramic material of low porosity.

Abstract: An alarm circuit for a transient voltage suppression circuit for protection of equipment using alternating current power is shown and described. This device utilizes a pair of diodes having the same terminals (polarity) connected to a node to which a resistor provides an AC voltage. The diodes conduct during one half cycle in normal operation, and the node is at a virtual ground when both diodes conduct. When a fuse from one diode to ground opens, current no longer flows and the voltage at the node rises as the other diode conducts and applies a voltage to resistors and an alarm input.There is also disclosed a suppression circuit which provides for isolation of the ground from neutral in the event of failure of the varistor.

Abstract: Electrical transient surge protection of electrical equipment downstream from a power source plus safeguarding of apparatus for providing such surge protection against failure at high currents or high temperature. Distributed-resistance fuse links facilitate operation of non-linear over-voltage means, such as varistors, in clipping transient voltage surges and shunting resulting currents to ground so as to protect watt-hour meters and downstream loads from electrical surges, and to safeguard such varistors from failure. Such apparatus may be located in such diverse places as a power line weatherhead, a watt-hour meter base, an adapter between a meter base and its normal mounting socket, or a utility panel having such a socket, or in a circuit-breaker panel downstream of the meter and upstream of metered loads.

Abstract: The invention is directed to power line filter and surge protection circuit components and the circuits in which they are used to form a protective device for electrical equipment. The circuit components comprise wafers or disks of material having desired electrical properties such as varistor or capacitive characteristics. The disks are provided with electrode patterns on surfaces thereof which coact with apertures formed therein so as to electrically connect the components to electrical conductors of a system easily and effectively. The electrode patterns act in conjunction with one another to form common electrodes with the material interposed therebetween. The electrode patterns are optimized in the circuit components such that balanced protection is achieved over all electrical conductors. The components also eliminate the use of leads such that operating characteristics are improved significantly.

Abstract: Electrical transient surge protection of electrical equipment downstream from a power source plus safeguarding of apparatus for providing such surge protection against failure at high currents or high temperature. Non-linear over-voltage means, such as varistors, function to clip transient voltage surges and to shunt resulting currents to ground so as to protect watt-hour meters and downstram loads from electrical surges. Adjacent arc-extinguishing components aid in safeguarding varistors or similar over-voltage means from potentially catastrophic destruction in the event of extreme over-heating from unusually frequent or prolonged surges. Such apparatus may be located in such diverse places as a power line weatherhead, a watt-hour meter base, an adapter between a meter base and its normal mounting socket, or a utility panel having such a socket, or in a circuit-breaker panel or even an electrical outlet receptacle downstream of the meter and upstream of metered electrical loads.

Abstract: An electrical device comprising a plurality of electrical assemblies formed as interchangeable modules, aligned in an end-to-end serial array and enclosed in a polymeric weathershed housing, the electrical assemblies being electrically and mechanically coupled together. Each electrical assembly in turn comprises a plurality of electrical components aligned in a row and in electrical connection with one another via their axially-directed ends and under an axially-directed compressive force via a nonconductive filament winding. The electrical components can be varistors, resistors, capacitors, and insulators or any combination thereof. In the case of varistors used to form a surge arrester, for example, voltage ratings can be enlarged merely by serially coupling a plurality of separately wrapped electrical components in the form of MOV blocks.

Abstract: An IC socket having internal MOV devices for protecting an integrated circuit from damage due to transient overvoltages.Each MOV device is coupled between a lead of the socket and a common metallic grounding strip contained within the IC socket. The grounding strip has an output lead which is brought through the socket for connection to a convenient system grounding point.

Abstract: Surge-protective varistors connected to shunt transient surges in electrical power lines to ground before damage to watt-hour meters or downstream loads. Conductive laminar members provide compact parallel circuit interconnection of varistors to increase the current-carrying capacity of protective apparatus containing them.

Abstract: The invention is directed to the provision of an external shield about the periphery of the housing of a surge arrester containing one or more arrester devices to provide an expansion limiting device which permits the housing to expand to a degree necessary to permit the expulsion of arc-generated gases within the housing while serving to help to limit the total expansion to a level below the elastic limit of the housing to prevent its destruction and permit its recovery after the gases have been dissipated. The shield may be made of metal, elastomeric materials, reinforced elastomeric materials or plastic, and the shield may be supported about the housing by an external strap of metal, plastic or elastomeric materials or may be supported by a plurality of fins arranged along the periphery of the housing and engaging an edge of the shield on its internal surface.

Abstract: A multiple outlet receptacle, such as one having four outlets in respective quadrants, is provided with a surge suppression circuit including a metal oxide varistor edgewise between the front and back of the device, other electronic elements, including dual status indicators, connected with an outer ring like contact plate and secured within portions of the insulating housings. Features for compactness and ease of assembly are provided. A pilot light indicator may alternatively be provided in receptacles without a surge suppressor utilizing some of the same components and assembly features.

Abstract: A multilayer varistor has alternating layers of ceramic material and electrode material. The layers are interleaved with each ceramic material layer sandwiched between two electrode material layers. One end portion of each electrode layer extends to an end face of the varistor where it is in electrical contact with an end terminal of the varistor. The other end of the layer is spaced by ceramic material from the opposite end terminal of the varistor. Thus alternate electrode material layers are in electrical communication with one and the other end terminal of the varistor unit. The ceramic material layer between each two electrode layers preferably has a thickness dimension less than 30.0 microns, or it may be formed by deposition of a powder suspension and subsequent heat treatment to provide a dense continuum of ceramic material of low porosity.

Abstract: A non-fragmenting surge arrester with a staged pressure relief mechanism includes a liner with outlets formed in the walls thereof, a gas expansion chamber within the liner and a housing having weakened-wall regions adjacent to the outlets in the liner. Ionized gas formed by an internal failure is vented from the expansion chamber through the outlets and, upon generation of sufficient pressure, fractures the housing at the weakened-wall regions. In this manner, the generated gas forms a lower impedance path for the current which is thereby shunted around the failed internal components, preventing the generation of further internal pressure which could cause a catastrophic failure of the arrester.

Abstract: An overload protector for a telecommunications system with an overcurrent protection device for each signal line in a chamber formed between a housing and a base and in which the base carries the line and ground pins and also an overvoltage device for each pair of the signal pins, the overvoltage device disposed at the base. In one construction, each overvoltage device comprises a solid state semi-voltage surge protection device at the base and a ground conductor extends laterally of the base between the ground pin and the device.

Abstract: A system is provided for connecting a suppressor for eliminating interference from electrical appliances. The system comprises an electrical box provided with a fitting for receiving a suppressor. The suppressor includes a plurality of angularly spaced contact arms. Terminal bodies which define terminal spaces for receiving conductor ends are disposed around the fitting. Terminal screws are provided at the terminal bodies. To electrically connect the suppressor to the conductor ends, the suppressor is inserted into the fitting and then rotated until the contact arms overlie the terminal bodies. The terminal screws are then tightened to simultaneously clamp the conductor ends within the terminal spaces and to clamp the contact arms between heads of the terminal screws and backs of the terminal bodies.

Abstract: To control the direction of movement and prevent random scattering of fragments of MOV blocks resulting from the catastrophic failure of such blocks during overvoltage incidents, a stack of such MOV blocks with end fittings attached is placed within a rigid filament-wound epoxy-impregnated tube formed as one continuous tube or a tube made up of aligned tube segments positioned so as to establish a preferred failure direction; the interstices between the interior of such tube and the exterior of said blocks and end fittings are filled with a dielectric insulative material which extends beyond and engulfs said tube and said end fittings to seal and further rigidify said component stack and provide an air-free non-electrically ionizable environment about said component stack.

Abstract: A material and device for electronic circuitry that provides protection from fast transient over-voltage pulses. The electroded device can additionally be tailored to provide electrostatic bleed. Conductive particles are uniformly dispersed in an insulating matrix or binder to provide material having non-linear resistance characteristics. The non-linear resistance characteristics of the material are determined by the inter-particle spacing within the binder as well as by the electrical properties of the insulating binder. By tailoring the separation between the conductive particles, thereby controlling quantum-mechanical tunneling, the electrical properties of the non-linear material can be varied over a wide range.

Abstract: A sealed envelope based on a filamentary winding constituted by resin-impregnated glass fibers, for equipment likely to be subjected to large thermal stresses and thus to be the seat of internal excess pressures, the winding adhering to the outside surface of the equipment, wherein the outside surface of the equipment coated with the winding has fiber-free zones forming resin-filled gaps, with the percentage of the surface area not covered with fibers being not less than about 15%.

Abstract: A non-fragmenting surge arrester core comprising a conductive core comprising a series array of non-linear resistor elements stacked in face-to-face contact between the inner end faces of a pair of terminal end pieces encased within a plastic impregnated jacket of bi-directional weave fabric woven of high tensile strength strands of which the strands of one of the bi-directional orientations have a greater tensile strength than the strands of the other bi-directional orientation with the greater strength fabric strands aligned lengthwise of the jacket. A tensioned constrictive hoop of high tensile strength material compressively circumscribes a portion of the jacket weave fabric overlying a peripheral area of the terminal end pieces between its two end faces, which peripheral area preferably conforms to a curvelinear depression groove circumscribing the terminal end pieces.

Abstract: A modular electrical assembly is enclosed in an elastomeric weathershed housing, and has a plurality of electrical components aligned in a row and in electrical connection with one another via their axially-directed ends and under an axially-directed compressive force via a non-conductive filament winding. The filament winding defines a crisscross pattern with lateral openings for venting gas upon failure of one of the electrical components. The openings can be filled with fracturable epoxy or other insulating materials such as silicone grease.

Abstract: A method and apparatus for suppressing electrical transient signals, occurring on power lines, includes a clamping circuit for switching from a high impedance to a low impedance at a certain switching voltage, to suppress the transient signals. A first blocking circuit inhibits the clamping circuit from switching to maintain it at its high impedance during normal line voltage, and permits the clamping circuit to switch to its low impedance for clamping purposes responsive to an initial portion of a transient signal for initial suppression purposes. A second blocking circuit has a second low impedance, which is substantially lower than said first low impedance of the first blocking circuit, for inhibiting substantially the first blocking circuit from continuing to dissipate the transient signal following the initial time period, and for permitting the clamping circuit to suppress the transient signal following the initial time period.

Abstract: A surge absorber utilizes a varistor electrically connected to a surge absorbing element. The varistor voltage and nonlinearity factor are chosen so that the varistor has a preselected voltage-current characteristic which prevents the varistor from breaking down and short circuiting and resulting in a thermal runaway.

Abstract: Surge suppression is provided by varistors connected between, respectively, hot and neutral conductors and hot and ground conductors, each through a common fuse that avoids hazardous overvoltages on the varistors. A first indicator circuit portion provides an indication that the power is on and surge protection is present and includes a first indicator device such as a green light-emitting diode that is energized when the fuse is intact, and a second indicator circuit portion is provided for indicating power is on and surge protection is lacking that includes a second indicator device such as a red light-emitting diode that is energized by the line conductors when the fuse has been interrupted. The surge suppressor and dual indicator apparatus can be contained within a wiring device such as a receptacle. A single varistor unit containing two varistor disks with three leads, including a center tap, allows three effective surge suppressor circuit branches in a compact configuration.

Abstract: A meter base surge suppression system is mountable on a meter mounting panel and is adapted to receive and hold a conventional electric meter. The surge suppression system includes a base plate having a plurality of openings through which contact prongs may be inserted, and an electrical contact element disposed about one of the openings for making electrical contact with a prong inserted through the opening. A surge suppression device is disposed on an upper side of the base plate and is coupled between the contact element and ground potential. A receiving plate is mountable on the base plate and is adapted to receive and hold a conventional electric meter. The receiving plate includes a plurality of buss elements which extend downwardly through the receiving plate and through the openings in the base plate to engage and be received into prong receptacles of a meter mounting panel on which the urge suppression system is mounted.

Abstract: Surge arrestor assemblies for railroad and like circuits utilize a high surface area to cross-sectional area, broadband equal potential grounding plane which is in the form of a loop. Surges are electrically coupled to the broadband equipotential grounding plane through surge arrestors. The assembly ensures that each arrestor "see's" the same impedance so that the voltage seen at the equipment is controlled. The grounding member is supported in recesses in mounting blocks which maintain its planar condition, and which also facilitate the connections to ground, lines, arresters and equipment.

Abstract: An excellent lightning arrestor insulator is provided having a discharge gap portion and an arrestor ZnO element device both built in a body of the insulator, comprising projected discharge electrodes arranged in the inside of the insulator body, the discharge gap portion being formed of a heat resistant protrusion arranged in the inside of the insulator body and surrounding the discharge electrodes, and a pair of metal plates and/or electrically conductive ceramic plates sandwiching the protrusion from both sides thereof and electrically connected to the discharge electrodes, the pair of plates being joined and airtightly sealed to the protrusion via an inorganic glass. The arrestor ZnO element device has a highly reliable airtight fixing and sealing structure so that accidents in a power supply or distribution line at a normal working voltage can be substantially eliminated, and damages caused by hygromeration and lightnings can be noticeably decreased.

Abstract: A plug-in surge suppressor module for insertion into a circuit breaker panel includes four stacks of metal oxide varistors (MOVs) arranged in a cloverleaf pattern on opposite sides of an elongated copper ground bus attached to one lead of each of the metal oxide varistors. The other leads of two of the stacks of metal oxide varistors are attached to a terminal of a U-shaped first resistive wire fuse, another terminal of which is connected to a first AC power line conductor. The other leads of the other two stacks of MOV's are attached to a terminal of a second U-shaped resistive wire fuse, another terminal of which is connected to a second AC power line conductor. A monitor circuit senses the presence of power and continuity of both fuses by pulsing a light emitting indicator diode every cycle of the AC line. A low frequency oscillator circuit produces slow blinking of the light emitting indicator diode which alerts an observer to replace te surge suppressor module if one of the fuses fails.