Abstract: A seal is described for sealing a fairlead of an object through a (housing) wall, wherein the seal surrounds the object with form fit at least in the area of the housing fairlead. The seal has an insulating rib encircling its circumference and a hydrophobic surface.

Abstract: The present invention relates to a method for calibrating a short-circuit indicator (1) for identifying a short circuit and/or a ground fault in a connected voltage grid (5) by means of an evaluation unit (3). A calibration unit (2) automatically measures at least one value of the currents and/or the voltages of the phases (1A, 1B, 1C) of the voltage grid (5), which value is characteristic of the normal operation of the voltage grid (5), and checks whether the measured characteristic value is within a validity range characterizing the normal operation. The calibration unit (2), in the event of successful checking, measures the normal values of the voltages and/or the currents of all phases (1A, 1B, 1C) of the voltage grid (5) and makes these normal values available to the evaluation unit (3) for identification of the short circuit and/or the ground fault and the direction of the fault location in the voltage grid (5).

Abstract: A signaling device for electrical monitoring devices, in particular for short circuit and/or ground fault indicators, and for optical, visually perceptible signaling with at least one luminous element is provided. The signaling device has a housing having a housing wall and a region formed in the housing wall so as to cover the luminous element. A printed circuit board is disposed in the housing. The luminous element is arranged within the housing and directly on the printed circuit board. The housing wall is formed such that it is at least light-transmissive in the region.

Abstract: A short-circuit indicator is provided for arrangement on an electrical line for electrical power distribution which includes a current transformer. The current transformer has an induction coil and an iron yoke for surrounding the electrical line to be monitored for a short-circuit current. The induction coil is seated on a base web of a U-shaped first yoke part. A second yoke part is connected in the form of a joint which can move between a closed position and an open position to one of two U-limbs of the first yoke part. The second yoke part forms a magnetic return path element for the first yoke part in the closed position. The first yoke part is split into two essentially L-shaped parts in the area of the base web to which the induction coil is fitted.

Abstract: A faulted indicator elbow-type termination connector for indicating the occurrence of a fault current in an electrical conductor of an alternating current distribution power system includes means for producing a magnetic field in response to an applied current to the electrical conductor. The termination connector includes a cylindrical body portion having a recessed housing section which projects radially from a central axis thereof. A faulted circuit indicator module is rotatably mounted within the recessed housing section and contains a trip setting device which is responsive to the magnetic field. The trip setting device has its sensitivity adjusted by rotating the faulted circuit indicator module relative to the cylindrical body portion. As a result, the sensitivity of the trip setting device can be changed quickly and easily so as to accommodate various trip settings.

Abstract: A faulted circuit indicator includes a variable load levelling circuit which can automatically adjust itself to a peak current in order to accommodate a relatively wide range of load currents. The variable load levelling circuit is operatively connected to a current sensing circuit and is responsive to a varying load current flowing through the cable for regulating a variable output voltage therefrom to be at a constant reference value. As a result, the need to store in inventory large quantities of fault indicators with different rated currents has been substantially reduced.

Abstract: A faulted circuit indicator unit for detecting an abnormally high electric current in an overhead cable includes a substantially rectangularly-shaped housing formed of front and back walls, opposed side walls, a closed bottom wall, and an open top mouth portion. Current sensing circuitry is disposed in a cavity formed in the housing for detecting the high current in the cable. An indication device is joined to the closed bottom wall of the housing and includes a visible indicator responsive to the current sensing circuit to produce a visual flashing light in the presence of the high current which is visible through a small aperture formed in the bottom wall thereof. The indication device is formed of an opaque hood whose central portion is connected around the bottom wall of the housing and a transparent stem joined also to the central portion of the hood and extends downwardly therefrom through which the flashing light is transmitted radially outwardly in all directions.

Abstract: A fault distance locator for underground cable circuits for calculating more accurately the location of a cable fault includes a pulse generator unit for injecting a series of chirped pulse streams into the faulted cable shortly after the cable fault has been established. The delay times between the reflected pulse signals and the sending pulse signals are obtained by a correlation process which is specially designed to eliminate the effect of noise caused by arcing voltage and thus provide an accurate calculation of the distance to the cable fault. The accuracy is further enhanced by injecting pre-fault pulse signals periodically into the cable prior to the occurrence of the cable fault in order to obtain a reference pulse signal. This pulse signal provides information concerning the speed of propagation of the cable and thus affects the distance calculation to the fault.

Abstract: A current transformer, which is able to be mounted with a switching bar on a conductor having a high voltage, has a coil surrounding a U-shaped iron yoke. A U-shaped ground iron is swivel-mounted on one leg of the iron yoke and is supported at a break point. Springs are anchored on a housing for the transformer. When the current transformer is mounted, the conductor moves the ground iron in a closing position and is maintained in such position by the springs.

Abstract: Error-free, reliable registration of a fault in a power distribution circuit is achieved by a faulted circuit indicator that measures the current in the circuit after a discrete time delay following the detection of an overcurrent condition. A fault is registered only if the measured current is less than a prescribed level, evidencing that the overcurrent has operated a protection device (such as a fuse), upstream from the faulted circuit indicator, to interrupt the circuit and clear the fault. Hence, only actual (true) faults, resulting in circuit interruption and isolation of the fault, will be indicated, thereby precluding false registrations that may otherwise occur from non-faults such as transient currents, momentary overloads, inrush currents, and the like.

Abstract: The fault indicator case has a concave mounting surface along which extend two legs having at their ends mounted jaws with serrated surfaces for engaging cable from below. Camming surfaces on the jaws facilitate placing the case on the cable. A shield can be fastened to the case after having been mounted.