A system and method for monitoring, testing or configuring electrical devices includes an input amplifier having an input connected to a device load line to generate an output linearly proportional to a voltage on the load line. An output of the input amplifier is connected to a photodiode in an optical path with a phototransistor. The phototransistor generates an output proportional to light generated by the photodiode, and this output is amplified and passed to an analog-to-digital converter. The converter generates a digital voltage level corresponding to the amplified output of the phototransistor. Digital temperature information is used to further enhance linearity of a generated digital voltage level. Multiple quantum well photodiodes further improve measurement linearity.

A battery system includes a battery module having a plurality of assembled batteries. Battery monitoring circuits are provided to correspond to each of the assembled batteries of the battery module. A control circuit controls operation of the battery monitoring circuits. A first signal transmission path transmits signals that are input and output between the battery monitoring circuits and the control circuit. A first isolation element is connected to the control circuit, and a second isolation element is connected to the battery monitoring circuit. The first signal transmission path is isolated from the control circuit by the second isolation element. The electrical potential of the first signal transmission path is a floating potential in relation to the electrical potentials of the control circuit and battery monitoring circuits.

A battery system includes a battery module having a plurality of assembled batteries. Battery monitoring circuits are provided to correspond to each of the assembled batteries of the battery module. A control circuit controls operation of the battery monitoring circuits. A first signal transmission path transmits signals that are input and output between the battery monitoring circuits and the control circuit. A first isolation element is connected to the control circuit, and a second isolation element is connected to the battery monitoring circuit. The first signal transmission path is isolated from the control circuit by the second isolation element. The electrical potential of the first signal transmission path is a floating potential in relation to the electrical potentials of the control circuit and battery monitoring circuits.

A leakage detection device includes at least one optical coupler, a voltage divider, an analog-to-digital converter and a processing unit. Wherein, the at least one optical coupler is adapted to output an electrical signal according to a leakage degree of a DC power supply. The electrical signal is divided by the voltage divider to be output to the analog-to-digital converter and converted into a digital signal. The processing is adapted to compare a digital value corresponding to the digital signal with a reference value and output a leak signal when a difference between the digital value and the reference value is greater than a predetermined difference. A battery pack includes a battery cell assembly, a switch element, and a control unit, wherein the control unit controls the switch element to switch off an electrical connection between the battery cell assembly and the load to block electric power to the load.

A system and method are provided for compensating for thermal drift of a probe device. The method includes monitoring a first temperature of a laser source in a sensor head that receives output electrical signals from a DUT and outputs corresponding optical signals; monitoring a second temperature of a photoreceiver in a probe interface that converts the optical signals to electrical test signals to input to the test instrument; calculating a first value of a first bias voltage using the first temperature; applying the first value of the first bias voltage to the laser source to compensate for thermal drift when the first temperature is within a first predefined temperature range; calculating a second value of a second bias voltage for the photoreceiver using the second temperature; and applying the second value of the second bias voltage to the photoreceiver to compensate for thermal drift when the second temperature is within a second predefined temperature range.

A system and method are provided for compensating for thermal drift of a probe device. The method includes monitoring a first temperature of a laser source in a sensor head that receives output electrical signals from a DUT and outputs corresponding optical signals; monitoring a second temperature of a photoreceiver in a probe interface that converts the optical signals to electrical test signals to input to the test instrument; calculating a first value of a first bias voltage using the first temperature; applying the first value of the first bias voltage to the laser source to compensate for thermal drift when the first temperature is within a first predefined temperature range; calculating a second value of a second bias voltage for the photoreceiver using the second temperature; and applying the second value of the second bias voltage to the photoreceiver to compensate for thermal drift when the second temperature is within a second predefined temperature range.

A system for measuring a current intensity of a current flowing through an electrical conductor (10), where the system includes a first component (1), which has the electrical conductor (10), and a second component (2), which is separate from the first component (1) and has an evaluation device (23), and a magnetic field-sensitive sensor element (3) and a connection line (4). The connection line (4) is a light guide. The sensor element (3) is non-releasably connected to the first end of the connection line (4) and/or to the first component (1). In the operating state, the two components 1(, 2) are DC-isolated from one another and are releasably connected to one another by means of the connection line (4) by way of a light-guiding connection, where the power supply to the magnetic field-sensitive sensor element (3) by the second component (2) and/or transmission of sensor data from the magnetic field-sensitive sensor element (3) to the evaluation device (23) is ensured by the light-guiding connection.

A system for measuring a current intensity of a current flowing through an electrical conductor (10), where the system includes a first component (1), which has the electrical conductor (10), and a second component (2), which is separate from the first component (1) and has an evaluation device (23), and a magnetic field-sensitive sensor element (3) and a connection line (4). The connection line (4) is a light guide. The sensor element (3) is non-releasably connected to the first end of the connection line (4) and/or to the first component (1). In the operating state, the two components 1(, 2) are DC-isolated from one another and are releasably connected to one another by means of the connection line (4) by way of a light-guiding connection, where the power supply to the magnetic field-sensitive sensor element (3) by the second component (2) and/or transmission of sensor data from the magnetic field-sensitive sensor element (3) to the evaluation device (23) is ensured by the light-guiding connection.

A schematic diagram of a wideband measurement system for mixed-connected CVT based on an optical voltage sensor is provided. The wideband measurement system comprises a CVT power frequency measurement section and an optical wideband measurement section. In the optical wideband measurement section, a low-voltage capacitor is connected in series between the low-voltage terminal and the ground terminal of the medium-voltage capacitor in the capacitor voltage divider. An optical voltage sensor is connected in parallel across the terminals of the low-voltage capacitor to measure the wideband voltage signal under test. The wideband measurement system for mixed-connected CVT described in the invention enables the CVT to have wideband measurement capabilities while ensuring the accuracy of conventional CVT power frequency measurements.

A schematic diagram of a wideband measurement system for mixed-connected CVT based on an optical voltage sensor is provided. The wideband measurement system comprises a CVT power frequency measurement section and an optical wideband measurement section. In the optical wideband measurement section, a low-voltage capacitor is connected in series between the low-voltage terminal and the ground terminal of the medium-voltage capacitor in the capacitor voltage divider. An optical voltage sensor is connected in parallel across the terminals of the low-voltage capacitor to measure the wideband voltage signal under test. The wideband measurement system for mixed-connected CVT described in the invention enables the CVT to have wideband measurement capabilities while ensuring the accuracy of conventional CVT power frequency measurements.