Abstract: A surge protective device (SPD) includes a jack and a plug detachably attached by insertion to the jack. Inside the plug, a protection circuit which protects equipment to be protected against intruding lightning surge, a degradation detecting unit which detects a degradation state of the protection circuit, a display unit which displays the detection result, or the like, are provided. When a plurality of SPDs are installed together, a juncture plug which detachably connects between juncture terminals within the adjacent SPDs is provided. The detection result of the degradation detecting unit within the plug is output to an outside through a third connection terminal within the plug, a first connection terminal and the juncture terminal within the jack and the juncture plug.

Abstract: A surge protective system has a plinth for wiring and is connected between a plurality of line side wires and a ground wire. A plurality of surge protective devices (SPDs) and one surge detector are disposed in parallel and detachably fitted into and attached to the plinth. The plinth has a wiring metal fitting for connecting the plurality of SPDs and the one surge detector. When a lightning surge current enters into the surge protective system from the line side wires, the lightning surge current flows to the surge detector through the SPDs, a 1st plinth contact part in the wiring metal fitting, a connection part and a 2nd plinth contact part. The lightning surge current flowing to the surge detector is discharged to the ground through the ground wire.

Abstract: An isolator 10 is formed with an isolation transformer 13 that blocks an abnormal voltage entering from a communication line 30 and protects a protection target device 40. A pulse transformer 43 in the device 40 includes a primary winding 43a connected to a secondary winding 13b of the transformer 13 and a secondary winding 43b connected to an inner circuit. A medium tap of the primary winding 43a is grounded through an inner capacitance Ci of the device 40. A parasitic capacitance Cs between the primary winding 13a and the secondary winding 13b of the transformer 13 and the inner capacitance Ci are connected in series, an abnormal voltage is divided by the capacitance Cs and the capacitance Ci, and a capacitance value of the capacitance Cs is set such that the divided voltage of the capacitance Ci is equal to or below a predetermined value.

Abstract: A lightning surge detector 1 includes a first terminal unit 3 connected to a ground-side terminal unit of a surge protective device, a second terminal unit 4 connected with a ground wire, a conducting coupling bar 5 adapted to couple the first terminal unit 1 and the second terminal unit 4, a detection coil 7 placed in a vicinity of the conducting coupling bar 5 and adapted to detect a lightning surge current flowing through the conducting coupling bar 5, a waveform processing unit adapted to stretch a voltage waveform of the detected lightning surge current and thereby output a waveform-modified voltage, a computation control unit adapted to produce a calculation result of the lightning surge current from the waveform-modified voltage, and a display unit 40 adapted to display the calculation result, wherein all the above components are unitized by being housed in a casing 2.

Abstract: A cam pin provided so as to project from a tip portion of an elastic tongue piece formed on a base unit of a protector S is inserted into a cam groove of a cam member disposed between the base unit and an operation member, and the operation member is moved in a direction in which the operation member moves away from or closer to a lower horizontal portion of the base unit to move the cam member, thus moving the cam pin between a locked position at which the cam pin a is positioned near a boundary between a inclined groove portion and a parallel groove portion of the cam groove of the cam member to inhibit the protector from being disengaged from a DIN rail and a unlocked position.

Abstract: An isolator 10 is formed with an isolation transformer 13 that blocks an abnormal voltage entering from a communication line 30 and protects a protection target device 40. A pulse transformer 43 in the device 40 includes a primary winding 43a connected to a secondary winding 13b of the transformer 13 and a secondary winding 43b connected to an inner circuit. A medium tap of the primary winding 43a is grounded through an inner capacitance Ci of the device 40. A parasitic capacitance Cs between the primary winding 13a and the secondary winding 13b of the transformer 13 and the inner capacitance Ci are connected in series, an abnormal voltage is divided by the capacitance Cs and the capacitance Ci, and a capacitance value of the capacitance Cs is set such that the divided voltage of the capacitance Ci is equal to or below a predetermined value.

Abstract: A cam pin provided so as to project from a tip portion of an elastic tongue piece formed on a base unit of a protector S is inserted into a cam groove of a cam member disposed between the base unit and an operation member, and the operation member is moved in a direction in which the operation member moves away from or closer to a lower horizontal portion of the base unit to move the cam member, thus moving the cam pin between a locked position at which the cam pin a is positioned near a boundary between a inclined groove portion and a parallel groove portion of the cam groove of the cam member to inhibit the protector from being disengaged from a DIN rail and a unlocked position.

Abstract: A surge current detection device 30 is detachably attached to a conductor 11 and detects a surge current entering the conductor 11. The surge current detection device 30 includes: a holder 40 releasably holding the conductor 11 via first and second holder bodies 40-1 and 40-2 facing each other; a magnetic force concentrating member 60 having a substantially U-shaped cross-section, the magnetic force concentrating member 60 being secured inside the holder 40 and concentrating a magnetic flux included in a magnetic field generated by the surge current entering the magnetic flux conductor 11 to a high density at a predetermined detection region; and a magnetic material sheet 70 secured inside the holder 40 in such a manner that the magnetic material sheet 70 is positioned at the detection region, the magnetic material sheet 70 detecting the surge current.

Abstract: A lightning surge detector 1 includes a first terminal unit 3 connected to a ground-side terminal unit of a surge protective device, a second terminal unit 4 connected with a ground wire, a conducting coupling bar 5 adapted to couple the first terminal unit 1 and the second terminal unit 4, a detection coil 7 placed in a vicinity of the conducting coupling bar 5 and adapted to detect a lightning surge current flowing through the conducting coupling bar 5, a waveform processing unit adapted to stretch a voltage waveform of the detected lightning surge current and thereby output a waveform-modified voltage, a computation control unit adapted to produce a calculation result of the lightning surge current from the waveform-modified voltage, and a display unit 40 adapted to display the calculation result, wherein all the above components are unitized by being housed in a casing 2.

Abstract: A protection element (e.g., an arrester) protects a piece of equipment to be protected, from surge currents line terminals and an earth terminal. Surge current detection devices are provided on respective conductors connected to the arrester. Each of the surge current detection devices is to detect the surge current penetrated into a conductor for a short period of time, and includes a magnetic flux concentration member by which a magnetic flux produced by the penetrated surge current is concentrated in a given detection area at a high density, and a ferromagnetic material sheet positioned on the given detection area. The ferromagnetic material sheet includes a recording layer which is able to record and erase the penetration state of the surge current. A plurality of microcapsules are arranged in the recording layer, and each of the microcapsules contains a suitable liquid, and a plurality of magnetic particles suspended in the suitable liquid.

Abstract: A surge current detection device 30 is detachably attached to a conductor 11 and detects a surge current entering the conductor 11. The surge current detection device 30 includes: a holder 40 releasably holding the conductor 11 via first and second holder bodies 40-1 and 40-2 facing each other; a magnetic force concentrating member 60 having a substantially U-shaped cross-section, the magnetic force concentrating member 60 being secured inside the holder 40 and concentrating a magnetic flux included in a magnetic field generated by the surge current entering the magnetic flux conductor 11 to a high density at a predetermined detection region; and a magnetic material sheet 70 secured inside the holder 40 in such a manner that the magnetic material sheet 70 is positioned at the detection region, the magnetic material sheet 70 detecting the surge current.

Abstract: A protection element (e.g., an arrester) protects a piece of equipment to be protected, from surge currents line terminals and an earth terminal. Surge current detection devices are provided on respective conductors connected to the arrester. Each of the surge current detection devices is to detect the surge current penetrated into a conductor for a short period of time, and includes a magnetic flux concentration member by which a magnetic flux produced by the penetrated surge current is concentrated in a given detection area at a high density, and a ferromagnetic material sheet positioned on the given detection area. The ferromagnetic material sheet includes a recording layer which is able to record and erase the penetration state of the surge current. A plurality of microcapsules are arranged in the recording layer, and each of the microcapsules contains a suitable liquid, and a plurality of magnetic particles suspended in the suitable liquid.

Abstract: The present invention relates to a grounding device in which a grounding member E having a grounding conductor 2 and a conductive laminated portion 5 covering the grounding conductor 2 is integrated with a foundation member B of a building so that the grounding member E and the foundation member B overlap partly or entirely. The grounding device is configured so that the grounding member having the grounding conductor and the conductive laminated portion covering the grounding conductor is integrated with the foundation member of the building are so that the grounding member and the foundation member overlap partly or entirely. This makes it possible to easily offer a small grounding resistance. Further, the foundation member of the building contacts the earth over a large area. This enables a small grounding resistance to be stably offered for a long period.

Abstract: In a surge protection device 40 (40-1 or 40-2) used for a surge protection apparatus, a gas arrester 41 is connected in series with a varister group consisting of a plurality of varisters 42-1 to 42-5 which have high withstand capacity and are connected in parallel to one another and a discharge resistor 43 is connected between both electrodes of the varister group. Besides, since the varister voltages are set higher than the peak value of the AC power supply voltage, the varisters 42-1 to 42-5 are normally insulated from a power supply circuit by the gas arrester 41. Even if an abnormal voltage is applied, since an operating voltage of the varisters 42-1 to 42-5 is set higher than a peak value of the AC power supply voltage, AC power supply current will not flow. Charges stored in the varisters 42-1 to 42-5 are released quickly through the resistor 43, making it possible to prevent the gas arrester 41 from restriking.

Abstract: A grounding conductor 1 is composed of a conductive metal portion 2 and a conductive casing portion 3 that covers the conductive metal portion 2. The conductive casing portion 3 has a specific resistance of 0.01 to 0. (?·m). Since the grounding conductor 1 is composed of the conductive metal portion 2 and the conductive casing portion 3 that covers the conductive metal portion 2, the conductive metal portion 2 is connected to the earth via the conductive casing portion 3. The conductive metal portion 2 does not contact directly with the earth but is electrically connected to the earth via the conductive casing portion 3. This prevents the conductive metal portion 2 from being corroded. It is also possible to avoid a disconnection in the conductive metal portion 2.

Abstract: The present invention relates to a grounding device in which a grounding member E having a grounding conductor 2 and a conductive laminated portion 5 covering the grounding conductor 2 is integrated with a foundation member B of a building so that the grounding member E and the foundation member B overlap partly or entirely. The grounding device is configured so that the grounding member having the grounding conductor and the conductive laminated portion covering the grounding conductor is integrated with the foundation member of the building are so that the grounding member and the foundation member overlap partly or entirely. This makes it possible to easily offer a small grounding resistance. Further, the foundation member of the building contacts the earth over a large area. This enables a small grounding resistance to be stably offered for a long period.

Abstract: A grounding conductor 1 is composed of a conductive metal portion 2 and a conductive casing portion 3 that covers the conductive metal portion 2. The conductive casing portion 3 has a specific resistance of 0.01 to 0. (?·m). Since the grounding conductor 1 is composed of the conductive metal portion 2 and the conductive casing portion 3 that covers the conductive metal portion 2, the conductive metal portion 2 is connected to the earth via the conductive casing prtion 3. The conductive metal portion 2 does not contact directly with the earth but is electrically connected to the earth via the conductive casing portion 3. This prevents the conductive metal portion 2 from being corroded. It is also possible to avoid a disconnection in the conductive metal portion 2.

Abstract: The present invention relates to a communication line surge protecting system in which a quarter wavelength open circuit for a wavelength used is disposed in each of a central conductor line 1 and an external conductor line 2 so as to allow a signal with a predetermined communication wavelength to pass therethrough, while blocking signals with frequency components of lighting surge and the like, and in which a ground line is further provided in the central conductor line and a quarter wavelength short circuit for the wavelength used is disposed in each of the ground line and the external conductor line so as to block the signal with the predetermined communication wavelength, while allowing the signals with the frequency components of lighting surge and the like to pass therethrough. The signal of the predetermined wavelength used passes through the communication line and is insulated from the ground.

Abstract: An optical repeating device with a monitoring function comprises first optical propagation means for propagating a lightwave signal through an optical transmission line, second optical propagation means butted against the first optical propagation means, for propagating the lightwave signal, optical branching means provided on a butting face between the first optical propagation means, and the second optical propagation means, and photodetection means. All the means described are assembled into a housing, and integrated therewith. Consequently, it is possible to downsize the optical repeating device with the monitoring function. A large portion of the lightwave signal propagated between the first optical propagation means and the second optical propagation means is allowed to pass through the optical branching means, however, a portion of the lightwave signal is reflected in a given direction by the optical branching means.

Abstract: A multi-terminal surge protection device able to absorb surges of either polarity between lines and between a line and ground, in which the difference in operating time between the device elements connected to lines is reduced. A plurality of unipolar surge protection device elements are used which only operate to absorb surges of a specific polarity, and do not exhibit a reverse withstand characteristic upon application of a reverse-polarity voltage. One element is connected to a first line and another element to a second line, while a different element is connected to ground. A semiconductor substrate and second electrode are used that are common to all elements. To prevent lateral interference between elements, at least the element connected to ground is isolated from the line elements.