Abstract: The invention relates to a method and a device for identifying and locating cyclic momentary insulation faults in an ungrounded power supply system, the method comprising the steps: detecting a fault current caused by the momentary insulation fault as a differential current in the branch circuit to be monitored and displaying the temporal progression of the differential current via a differential current signal by means of a differential current sensor; providing a processing signal which temporally describes a process sequence of a process taking place in the consumer; correlating the differential current signal with the processing signal in a computing unit in order to yield a correlation signal as a measure for a temporal match between the differential current signal and the processing signal; signaling the momentary insulation fault via the computing unit by means of a signaling signal if the correlation signal shows the temporal match.

Abstract: A grounded socket and a method for insulation fault location in an ungrounded power supply system including insulation monitoring by a standard insulation monitoring device superimposing a measuring voltage on the ungrounded power supply system for determining an insulation resistance of the ungrounded power supply system. The grounded socket includes a housing having electrical contacts, a signaling device for signaling an insulation state, and a current measuring device for detecting and evaluating a differential current, the current measuring device having a measuring current transformer and evaluating electronics, and the current measuring device being configured for high-resolution detection and evaluation of a measuring current driven by the measuring voltage as a differential measuring current.

Abstract: Methods and electric circuit arrangements for protecting metallic components in an electrolytic medium from corrosion due to direct-current (DC) stray current (Is) from a power supply system. The DC stray current may be jointly registered as a total sum current across all active conductors together with the protective conductor of the power supply system by a DC total differential-current sensor. Alternatively, a combined DC differential-current sensor is switchable by a switching device, a differential current being registered across all active conductors or the DC stray current being registered as a total differential current across all active conductors and the protective conductor.

Abstract: A method and a measuring device for detecting a leakage current in an ungrounded, single-phase alternating-current power supply system. A variable test resistance is switched between one of the outer conductors and ground and starting from a minimally admissible test-resistance value, at least one of three support test-resistance values is determined as support locations. In an equivalent circuit of the modeled alternating-current power supply system, an equations system is set up for describing the dependency of currents and voltages. An extrapolation on the test-resistance value zero leads to a calculated test current which corresponds to the leakage current to be detected. Consequently, a ground fault situation may be simulated without actually causing a dangerous ground fault.

Abstract: The invention relates to a method and a device for identifying and locating cyclic momentary insulation faults in an ungrounded power supply system, the method comprising the steps: detecting a fault current caused by the momentary insulation fault as a differential current in the branch circuit to be monitored and displaying the temporal progression of the differential current via a differential current signal by means of a differential current sensor; providing a processing signal which temporally describes a process sequence of a process taking place in the consumer; correlating the differential current signal with the processing signal in a computing unit in order to yield a correlation signal as a measure for a temporal match between the differential current signal and the processing signal; signaling the momentary insulation fault via the computing unit by means of a signaling signal if the correlation signal shows the temporal match.

Abstract: A method and a measuring device for detecting a leakage current in an ungrounded, single-phase alternating-current power supply system. A variable test resistance is switched between one of the outer conductors and ground and starting from a minimally admissible test-resistance value, at least one of three support test-resistance values is determined as support locations. In an equivalent circuit of the modeled alternating-current power supply system, an equations system is set up for describing the dependency of currents and voltages. An extrapolation on the test-resistance value zero leads to a calculated test current which corresponds to the leakage current to be detected. Consequently, a ground fault situation may be simulated without actually causing a dangerous ground fault.

Abstract: The invention relates to an electric circuit arrangement (20) for the functional testing of a monitoring device (4) for a power supply system (2), the electric circuit arrangement (20) having a test resistance (Rf1, Rf2) which is switched between an active conductor (L1, L2) of the power supply system (2) and ground (PE) and has a settable actual resistance value (Rx). In this context, a bidirectional cascade (12) consisting of field-effect transistors as test resistances (Rf1, Rf2) and an analog control (10) for the continuous-value setting of the actual resistance value (Rx) to a predefined target resistance value (R0) are provided.

Abstract: A grounded socket and a method for insulation fault location in an ungrounded power supply system including insulation monitoring by a standard insulation monitoring device superimposing a measuring voltage on the ungrounded power supply system for determining an insulation resistance of the ungrounded power supply system. The grounded socket includes a housing having electrical contacts, a signaling device for signaling an insulation state, and a current measuring device for detecting and evaluating a differential current, the current measuring device having a measuring current transformer and evaluating electronics, and the current measuring device being configured for high-resolution detection and evaluation of a measuring current driven by the measuring voltage as a differential measuring current.

Abstract: The invention relates to an electric circuit arrangement (20) for the functional testing of a monitoring device (4) for a power supply system (2), the electric circuit arrangement (20) having a test resistance (Rf1, Rf2) which is switched between an active conductor (L1, L2) of the power supply system (2) and ground (PE) and has a settable actual resistance value (Rx). In this context, a bidirectional cascade (12) consisting of field-effect transistors as test resistances (Rf1, Rf2) and an analog control (10) for the continuous-value setting of the actual resistance value (Rx) to a predefined target resistance value (R0) are provided.

Abstract: A method and device for determining a division of a total insulation resistance and of a total system leakage capacitance in an ungrounded power supply system. The basic idea is to determine how the total insulation resistance is divided into partial insulation resistances and how the total system leakage capacitance is divided into partial system leakage capacitances between the active conductors of the ungrounded power supply system from displacement voltages measured between each of the active conductors of the ungrounded power supply system based on values determined in advance for the total insulation resistance and for the total system leakage capacitance of the ungrounded power supply system. By evaluating the displacement voltages in terms of their changes in amplitude, their frequency and their phasing, conclusions can be drawn as to the division of the total insulation resistance and of the total system leakage capacitance between the individual active conductors.

Abstract: A method and device for determining a division of a total insulation resistance and of a total system leakage capacitance in an ungrounded power supply system. The basic idea is to determine how the total insulation resistance is divided into partial insulation resistances and how the total system leakage capacitance is divided into partial system leakage capacitances between the active conductors of the ungrounded power supply system from displacement voltages measured between each of the active conductors of the ungrounded power supply system based on values determined in advance for the total insulation resistance and for the total system leakage capacitance of the ungrounded power supply system. By evaluating the displacement voltages in terms of their changes in amplitude, their frequency and their phasing, conclusions can be drawn as to the division of the total insulation resistance and of the total system leakage capacitance between the individual active conductors.

Abstract: The invention relates to circuit arrangements for reducing potential-induced degradation in photovoltaic modules of a photovoltaic generator, said circuit arrangements comprising an insulation monitoring device for a temporally continuous insulation monitoring of the photovoltaic generator. Furthermore, the invention relates to a photovoltaic system comprising a circuit arrangement for reducing potential-induced degradation in photovoltaic modules, said photovoltaic system comprising a photovoltaic generator and an insulation monitoring device for a temporally continuous insulation monitoring of the photovoltaic generator. Different solutions are proposed which enable reducing potential-induced degradation while simultaneously continuously monitoring insulations. The circuit arrangements according to the invention rest upon an insulation monitoring device interacting with measures based circuit technology for influencing potentials in a photovoltaic module.

Abstract: A method and device for determining a division of a total insulation resistance and of a total system leakage capacitance in an ungrounded power supply system. The basic idea is to determine how the total insulation resistance is divided into partial insulation resistances and how the total system leakage capacitance is divided into partial system leakage capacitances between the active conductors of the ungrounded power supply system from displacement voltages measured between each of the active conductors of the ungrounded power supply system based on values determined in advance for the total insulation resistance and for the total system leakage capacitance of the ungrounded power supply system. By evaluating the displacement voltages in terms of their changes in amplitude, their frequency and their phasing, conclusions can be drawn as to the division of the total insulation resistance and of the total system leakage capacitance between the individual active conductors.

Abstract: The invention relates to circuit arrangements for reducing potential-induced degradation in photovoltaic modules of a photovoltaic generator, said circuit arrangements comprising an insulation monitoring device for a temporally continuous insulation monitoring of the photovoltaic generator. Furthermore, the invention relates to a photovoltaic system comprising a circuit arrangement for reducing potential-induced degradation in photovoltaic modules, said photovoltaic system comprising a photovoltaic generator and an insulation monitoring device for a temporally continuous insulation monitoring of the photovoltaic generator. Different solutions are proposed which enable reducing potential-induced degradation while simultaneously continuously monitoring insulations. The circuit arrangements according to the invention rest upon an insulation monitoring device interacting with measures based circuit technology for influencing potentials in a photovoltaic module.

Abstract: A method and device for insulation fault monitoring in ungrounded electrical networks. The method includes the following steps: measuring an insulation resistance, determining a responding value for the insulation resistance, and triggering a warning signal if the measured insulation resistance falls below the responding value, wherein the responding value is determined dynamically as a momentary responding value in a warning value establishment process downstream of the insulation resistance measurement.

Abstract: A method for processing and displaying insulation resistance values in insulation fault monitoring devices for an IT power supply system includes determining an insulation resistance value in predetermined time intervals, detecting an insulation fault if the determined resistance value falls below a preset limit value, showing an optical alarm message if the insulation fault is present, wherein the determined insulation resistance value is time stamped and stored, the time stamp marked as the alarm time upon detection of the insulation fault, after determining and storing n insulation resistance values following the alarm time, a number n of the insulation resistance values determined prior to the alarm time, the insulation resistance value determined at the alarm time and a number n of the insulation resistance values determined after the alarm time are copied into a cache and graphically displayed.

Abstract: The invention relates to a method and a device for monitoring the insulation of an ungrounded DC and/or AC voltage network. The method includes the following steps: (a) generating a measurement DC voltage Umess= that is connected to a ground on one side for a tvar; predeterminable measuring time frame tvar; (b) generating and superposing at least one measurement AC voltage Umess˜ connected to a ground and having a measurement duration tcons with the measurement DC voltage Umess? for forming a total measurement voltage Umess; (c) feeding the total measurement voltage Umess into the voltage network to be monitored; and (d) determining an insulating resistance R= from the measurement DC voltage Umess? and an insulating impedance Z from the measurement AC voltage Umess˜. The devise is configured to carry out the above method. The method and the device are suited in particular for monitoring the insulation in electric and hybrid vehicles.

Abstract: A method and to a device for insulation monitoring in ungrounded electrical direct or alternating current networks includes coupling in a measuring signal between active conductors of the network to be monitored and ground and registration of measured values of the measuring signal. The registered measured value of the measuring signal is determined in the form of a signal quality value which is displayed on a display.

Abstract: A method and device for insulation fault monitoring in ungrounded electrical networks. The method includes the following steps: measuring an insulation resistance, determining a responding value for the insulation resistance, and triggering a warning signal if the measured insulation resistance falls below the responding value, wherein the responding value is determined dynamically as a momentary responding value in a warning value establishment process downstream of the insulation resistance measurement.

Abstract: The invention relates to a method and a device for monitoring the insulation of an ungrounded DC and/or AC voltage network. The method comprises the following steps: (a) generating a measurement DC voltage Umess= that is connected to a ground on one side for a predeterminable measuring time frame tvar; (b) generating and superposing at least one measurement AC voltage Umess˜ connected to a ground and having a measurement duration tcons with the measurement DC voltage Umess? for forming a total measurement voltage Umess; (c) feeding the total measurement voltage Umess into the voltage network to be monitored; and (d) determining an insulating resistance R= from the measurement DC voltage Umess? and an insulating impedance Z from the measurement AC voltage Umess˜. The devise is configured to carry out the above method. The method and the device are suited in particular for monitoring the insulation in electric and hybrid vehicles.