Abstract: For testing a transformer (20) the transformer (20) is emulated by an equivalent circuit (30) and an accuracy of the transformer (20) relative to the equivalent circuit (30) is determined by evaluating a test response of the transformer (20) and is then automatically converted to an operating condition-related accuracy of the transformer (20).

Abstract: The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6): generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20). Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation. Determining a curve of an electrical measurement variable (I; I1; I2) of the transformer (5; 6) over time (t) respectively during the step of actuating the tap changer (20) depending on the test signal. automatically illustrating the curves (41, 42) in a temporally-superimposed manner.

Abstract: The present method relates to a method for checking a multi-pole electrical circuit breaker. The multi-pole electrical circuit breaker comprises a plurality of poles (101-103). Each of the plurality of poles (101-103) comprises a first connection (121-123) and a second connection (131-133). Closing the particular pole (101-103) makes it possible to electrically connect the first connection (121-123) of the particular pole (101-103) to the second connection (131-133) of the particular pole (101-103) via the pole. In the method, a plurality of micro-ohm measurements are carried out at the plurality of poles (101-103), while the plurality of poles (101-103) are earthed on both sides in a P-P-P-E configuration. A contact resistance of one of the plurality of poles (101-103) is determined on the basis of the plurality of micro-ohm measurements.

Abstract: The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6): generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20). Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation. Determining a curve of an electrical measurement variable (I; I1; I2) of the transformer (5; 6) over time (t) for each actuation of the tap changer (20) depending on the test signal. Filtering the curves (41, 42) in order to prevent at least one of the curves (41, 42) from being output. Outputting the filtered curves (41; 42).

Abstract: A method for testing multiple spatially distributed protective devices of an energy supply network. Each of the protective devices is configured to, in the event of a fault occurring in the energy supply network, isolate the fault in the energy supply network. The method comprises: producing an initial test sequence; outputting of the test sequence to the protective devices; detecting outputs of the protective devices that the protective devices output on the basis of the test sequence; analyzing the outputs and generation of inputs for the protective devices depending on the outputs. If the inputs are not part of the test sequence, these inputs are incorporated into the test sequence and the outputting step proceeds. Otherwise, all outputs of the protective devices are evaluated. Each test sequence comprises inputs in the form of process variables of the energy supply network for at least one of the protective devices.

Abstract: A contact-making device (10) is used for a resistance measurement on a test object (30). The test object (30) comprises a threaded hole (31), which has an internal thread (32). The contact-making device (10) is designed to be mechanically coupled to the internal thread (32) of the threaded hole (31). The contact-making device (10) comprises a first contact (11) and a second contact (12), in order to make electrical contact with the test object (30) at, at least, two points when the contact-making device (10) is mechanically coupled to the internal thread (32). The first contact (11) and the second contact (12) are electrically insulated from one another by an insulating material (15-17) in the contact-making device (10).

Abstract: A method and a system (9) for testing a switching installation (30) for power transmission installations are provided. The switching installation (30) comprises a switch (2) which either connects a first side (6) of the switch (2) to a second side (7) of the switch (2) or disconnects it therefrom, and comprises two earthing switches (10, 11). Each of the two earthing switches (10, 11) is provided to either connect the first side (6) or the second side (7) to earth (1) or to disconnect it from earth (1). To test the switching installation (30), a current is generated through the switch (2) and a magnitude of the current through the switch (2) is determined. In this respect, the two earthing switches (10, 11) are closed while the current is generated and while the magnitude of the current is determined.

Abstract: An apparatus and method for the measurement of a resistance of a switching contact of an electrical circuit breaker. A first resistance value across the circuit breaker is determined while the circuit breaker is grounded at both sides and the switching contact is closed. Further, a second resistance value across the circuit breaker is determined while the circuit breaker is grounded at both sides and the switching contact is open. The resistance of the closed switching contact is then determined based on the first resistance value and the second resistance value.

Abstract: A method and a measuring device for monitoring a power transmission line are disclosed. Measured data are acquired by means of the measuring device at a measuring point of the power transmission line and are coupled in to said power transmission line to transmit the measured data via the power transmission line to a measured data acquisition device.

Abstract: In order to check a switching operation of an electric switch (1-3), a movement of a movable switching element (1) of the electric switch (1-3) is sensed during the switching operation. For that purpose, a marking element (11) is used, the marking element (11) having a magnetization pattern comprising a plurality of magnetic markings. A path length (9) of a relative movement between the marking element (11) and a sensor (12) is determined.

Abstract: In order to test a power engineering test object (14), a test signal is generated by a first test device (2), which is supplied by the first test device (2) to a second test device (3) to be amplified by the same and to be output to the power engineering test object (14). Further, the test signal may be applied by the first test device (2) to the power engineering test object (14), the test signal preferably being time-synchronously output by the first test device (2) and the second test device (3) to the power engineering test object (14).

Abstract: The present invention relates to a measuring device (10) for measuring a resistance of a switching contact (5) of an electrical circuit breaker (1). The measuring device (10) comprises a high-current generating unit (11) for generating a measurement current for the resistance measurement, and a measuring unit (12) for registering a measurement signal at the circuit breaker (1) during the opening or closing of the switching contact (5), and for determining a time-based resistance course of the switching contact (5) during opening or closing, in dependence on the measurement current and the measurement signal.

Abstract: This invention concerns methods and devices for calibrating a partial discharge measuring device and for locating faults on cables. In the method, calibration signals, which can include a band-limited white noise, are used with a periodically repeated signal course. By averaging over a predetermined period duration (T) of the calibration signal, it is possible, in the case of a partial discharge measurement, to recalibrate the measuring device continuously during the measurement, and additionally on cables to determine the fault location with great precision.

Abstract: An apparatus and method for the measurement of a resistance of a switching contact of an electrical circuit breaker. A first resistance value across the circuit breaker is determined while the circuit breaker is grounded at both sides and the switching contact is closed. Further, a second resistance value across the circuit breaker is determined while the circuit breaker is grounded at both sides and the switching contact is open. The resistance of the closed switching contact is then determined based on the first resistance value and the second resistance value.

Abstract: A test device (1) for testing power engineering equipment comprises at least one connection socket (4) which is electrically connected to an overvoltage protection arrangement (2). The overvoltage protection arrangement (2) comprises at least one overvoltage protection element (5) and is configured such that the at least one overvoltage protection element (5) is exchangeable.

Abstract: For diagnosing a self-blast circuit breaker (1), a switching operation of the self-blast circuit breaker (1) is triggered to initiate a pressure wave in a filling gas of the self-blast circuit breaker (1). A pressure as a function of time in at least one region of the self-blast circuit breaker (1) which occurs in response to the switching operation is detected. A state of a burn-off nozzle (11) of the self-blast circuit breaker (1) which is burnt off in a switching operation under load for blowing the filling gas onto a switching arc is determined in dependence on the pressure as a function of time.

Abstract: Method and device for monitoring the status of a sheath voltage arrester of a cable system, a verification signal being supplied to a measuring loop which comprises the sheath voltage arrester and a measurement signal which is subsequently produced in accordance with the frequency-dependent impedance of the sheath voltage arrester being measured at the measuring loop in order to establish the status of the sheath voltage arrester by evaluating the measurement signal.

Abstract: Measuring device for checking an electrical circuit breaker includes a current generating unit designed to generate a measurement current for a continuity measurement of a switching contact of the circuit breaker. The measuring device furthermore includes a measuring unit for registering a measurement signal at the circuit breaker, an energy supply unit for supplying a control drive of the circuit breaker with electrical energy, and a control unit, which has a timer. The control unit is able output to the control drive, via the control output, a signal for opening or closing the circuit breaker, and to determine a time-based switching behavior of the circuit breaker in dependence on the measurement signal. Further, the control unit is designed, in the case of the circuit breaker being closed, to determine the resistance of the switching contact in dependence on the measurement current and the measurement signal.

Abstract: The present invention relates to a method for determining partial discharges at an electrical component (10). In the case of the method, an electrical signal that comprises partial discharge pulses due to the partial discharges at the electrical component (10) is detected. Through filtering of the electrical signal by means of n filters (18-20) having n differing filter characteristics, n filtered partial discharge signals are generated. Respectively one of the filtered partial discharge signals is assigned, respectively, to one of the n filters (18-20), n being greater than or equal to two. Finally, the partial discharges are determined by linking the n filtered partial discharge signals.