Methods and systems are described for diagnosing a multiple speed, relay controlled engine cooling fan system. One method includes measuring the change in current drawn from a battery-alternator system when fan speed is modified. A degradation in cooling fan operation is flagged when measured current change differs from an expected change.

A system for automatically commissioning a solar panel array comprises a plurality of panel monitoring devices, each panel monitoring device connected between a positive and negative terminal of a solar panel. Each panel monitoring device comprises a switching device, the switching device configurable to disconnect an output from the solar panel. The system further comprises logic configured to automatically obtain a relative position of each panel monitoring device in the system by appointing serially a series of masters from among the panel monitoring devices, each master in turn broadcasting a unique identifier and enabling its output. Each panel monitoring device listens to the masters' broadcasts and stores in memory the unique identifier and information indicating whether the panel monitoring device detected the masters' voltage. The panel monitoring devices determine their respective locations by analyzing the information broadcast by, and the voltage detected from, the masters.

This disclosure describes a driver circuit configured to control a gate injection transistor (GIT). The driver circuit is configured to output a control current to a gate of the GIT, detect a voltage at the gate of the GIT, and determine a load current through the GIT based on the voltage detected at the gate of the GIT. The voltage at the gate of the GIT may be dependent on both the load current and the control current.

Methods and devices for detecting frictional interference of one or more mechanical components within a vehicle that are driven by an electric motor. The testing includes: determining that an amount of current drawn by the electric motor while driving the one or more mechanical components is above a predetermined threshold; detecting vibrations caused by the one or more mechanical components while being driven by the electric motor; analyzing the vibrations by a Fast Fourier Transform (FFT); and based on an output from the FFT, determining the frictional interference of the one or more mechanical components.

A system monitoring method is used in a multicarrier system comprising a rail (2) along which plural individually drivable electric drive elements (5) are disposed, and at least one carrier (1) drivable by said drive elements (5) along said rail (2) preferably in any of the two rail directions. The method comprises simultaneously driving plural of said drive elements (5) such that their driving forces exerted on the carrier (1) counteract each other, while driving said drive elements (5), observing an electric quantity, preferably a voltage or a current, at one or more or all of said drive elements (5) with one or more current sensors (23), and evaluating the observed electric quantities and drawing a conclusion on drive element operation and/or sensor operation based on said evaluation.

Systems, methods, and apparatus, including computer programs encoded on computer-readable media, for monitoring an electromotive force (EMF) for an electrical submersible pump (ESP) having a permanent magnet motor (PMM) are disclosed. One or more voltages and one or more currents may be monitored in a cable coupled to the ESP having the PMM and being used in a well system. It may be determined whether at least one of the one or more voltages in the cable exceeds a voltage threshold and whether at least one of the one or more currents in the cable exceeds a current threshold. A notification may be generated to indicate an EMF condition if at least one of the one or more voltages and the one or more currents in the cable exceeds at least one of the one or more thresholds.

Detecting voltage-based attacks on an integrated circuit (IC) is difficult in the presence of clock jitter. Propagating signals can exhibit a total delay that is due to a delay component resulting from a voltage-based attack and a delay characteristic resulting from clock fluctuation. Voltage-variation detection circuitry includes first and second voltage-dependent circuits and a voltage analysis circuit. The voltage-dependent circuits produce first and second signals that are indicative of a voltage level responsive to a clock signal and based on different first and second voltage sensitivities. The voltage analysis circuit generates a voltage alert signal based on the first and second signals. A combined signal neutralizes the delay characteristic in the first and second signals, but the delay component due to the voltage variation can be at least partially maintained. Thus, a voltage-based attack is detectable in the presence of clock fluctuation by using two voltage-dependent circuits.

This abnormality detection circuit is configured so as to detect abnormality of a first half bridge including a first switching element and a second switching element. The abnormality detection circuit includes: a series circuit of a first switch and a first resistor provided between a first node which is a connection node for the first switching element and the second switching element and a second node configured so as to have a first constant voltage applied thereto; and a first comparator configured so as to compare a first reference voltage and a voltage corresponding to the voltage of the first node.

A diagnosis system diagnoses the integrity of an opening/closing device capable of opening and closing by driving a motor. A driving current acquisition unit acquires a driving current of the motor. A diagnosis unit defines a current waveform from a temporal change of the driving current acquired by the driving current acquisition unit and diagnoses the integrity of the opening/closing device based on the current waveform.

A dual differential contactless current sensor uses a pair of magnetic sensors placed adjacent to a conductor, such as a metallic trace on a printed circuit board, which is conducting electrical current. The ability to detect and measure a tampering magnetic field in such a sensor is provided by a circuit that sums the outputs of the pair of magnetic sensors. The circuit can output an alarm signal, such as a programmable one-bit alarm that indicates when the external magnetic field exceeds a programmed threshold, or an analog voltage proportional to the external field. The alarm signal can be polled by additional circuitry that indicates to the stakeholders that a party is attempting to alter the power measurement.