Examples described herein provide a computer-implemented method that includes monitoring, using a microcontroller, an electric circuit of a vehicle, the electric comprising a battery source and a load. The battery source supplies electric power to the load. The method further includes detecting, using the microcontroller, a high current event in the electric circuit by comparing a current level of a current flowing through the electric circuit to a time-based current threshold. The method further includes responsive to detecting the high current event, controlling a gate driver to cause a switch of an electronically resettable fuse to open the electric circuit to stop the flow of the current through the electric circuit.

Systems and methods for providing information about thermal overload conditions and near-miss tripping events in a circuit interrupter are disclosed. The systems and methods provide a user with detailed information about thermal overload and near-miss tripping events, including how much time remains until a trip will be initiated due to a thermal overload, and what the real-time thermal capacity of the circuit interrupter is after a thermal overload condition ends.

The processing device includes: a temperature transition acquisition unit that acquires rising transition of the temperature of the winding in a state in which a first voltage is applied in order to raise a temperature of the winding to a first temperature and further acquires falling transition of the temperature of the winding in a state in which a second voltage is applied in order to lower the temperature of the winding to a second temperature that is lower than the first temperature after the temperature of the winding converges to the first temperature; and a decision unit that calculates stator-related parameters on the basis of the falling transition to decide a stator temperature characteristic mode and further calculates winding-related parameters on the basis of the rising transition and a stator temperature characteristic model to decide a winding temperature characteristic model.

A thermal monitoring system includes thermal monitoring devices that generate sensor data including thermal images depicting monitored elements (e.g. of an electrical switchgear system). The sensor data for all monitoring devices installed at a local deployment is collected by a gateway device, and relevant data from multiple local deployments is further aggregated by a cloud management system for further analysis. New event triggering rules determining how the thermal monitoring devices filter or record the sensor data are generated based on the aggregated data during a continuous learning process. The system detects patterns in the sensor data for the monitoring devices and/or local deployments as a whole and tracks deviations from these patterns, improving the accuracy of the event detection over time.

An induction motor overheat monitoring method and device detects overheating of an induction motor from a detection value of a current sensor. A resistance calculation relationship data indicating a relationship between a resistance and a feature amount at the time of starting of the induction motor and a determination reference value for determining overheating are stored in advance. At each starting, a current of the induction motor is detected, a signal regarding a phase angle difference is calculated, and a feature amount of the motor is calculated from the signal regarding the phase angle difference. Further, a resistance of the induction motor is calculated by using the feature amount of the motor and the resistance calculation reference data stored in advance. Then, a temperature of the induction motor is calculated from the resistance of the induction motor, and it is determined if the motor is overheated.

A relay temperature measuring device is provided. The device includes a sensor that measures an output of a battery and generates output measurement information and one or more relays that are disposed on a conductive line between the battery and a load. Additionally, a controller compares a relay temperature calculated using both-end measurement power information generated by measuring both ends of a conductor in a vehicle and the output measurement information with a preset temperature reference value, and connects or disconnects the relays based on a comparison result.

In a power supply control device, a temperature calculation circuit calculates a wire temperature of a wire based on the current value of a current flowing through the wire. If the wire temperature calculated by the temperature calculation circuit is lower than a temperature threshold value, a drive unit switches on or off a switch in accordance with content indicated by a control signal output by a communication unit. When the wire temperature calculated by the temperature calculation circuit rises to the temperature threshold value or higher, the drive unit switches off the switch independently of content indicated by a control signal output by the communication unit.

A relay temperature measuring device is provided. The device includes a sensor that measures an output of a battery and generates output measurement information and one or more relays that are disposed on a conductive line between the battery and a load. Additionally, a controller compares a relay temperature calculated using both-end measurement power information generated by measuring both ends of a conductor in a vehicle and the output measurement information with a preset temperature reference value, and connects or disconnects the relays based on a comparison result.

Motor overload protection device is equipped with a thermal monitor that can determine expected rotor temperature rise from rotor resistance estimates. The thermal monitor determines expected rotor temperature rise by using a correlation between rotor temperature rise computed from rotor resistance estimates, and motor thermal state estimates. The correlation can be derived by fitting a line to a plurality of points, with each point defined by an ordered pair composed of a rotor temperature rise estimate and a corresponding motor thermal state estimate, and determining a slope of the line. This rotor temperature slope can then be used by the thermal monitor to determine a rotor temperature rise given a rotor resistance estimate and a corresponding motor thermal state estimate. If the rotor temperature rise exceeds an expected rotor temperature rise by more than a predefined threshold, the thermal monitor issues an alarm and/or takes corrective actions in some embodiments.

The invention relates to a method for operating a power tool, according to which a measuring device determines a winding resistance (R.sub.S) of a winding of an electric motor of the power tool. A test signal source applies a test signal (i.sub.p) to the winding during operation of the electric motor, a measuring unit records at least one measured value (U.sub.d, i.sub.d) as a reaction of the winding to the test signal (i.sub.p), and a control device determines the winding resistance (R.sub.S) while taking into consideration the measured value (U.sub.d, i.sub.d).