In described examples, a switch has: a first current handling terminal coupled to a supply source terminal; and a second current handling terminal coupled to an output terminal. A comparator has: a first input coupled to the second current handling terminal; and a second input. A voltage reference source has: a first terminal coupled to the first current handling terminal; and a second terminal coupled to the second input of the comparator. A slew rate detector has an input coupled to the second current handling terminal. A switch controller has: a first input coupled to the comparator output; and a second input coupled to an output of the slew rate detector. The switch controller is coupled to output a signal to cause the switch to open when the comparator detects an over-current condition through the switch while the slew rate detector detects a negative slew rate.

A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.

A lamp is provided. The lamp includes at least one light emitting diode (LED) and an electronic circuit configured to provide power to the at least one LED. The lamp includes at least one flat circuit board having mounted thereto the at least one LED and the electronic circuit. The at least one flat circuit board acts as a heatsink to dissipate heat from the at least one LED and acts as a plurality of circuit paths for the electronic circuit and the at least one LED.

A power supply system includes a power conditioning apparatus, a transformer, and a controller. The power conditioning apparatus includes an inverter circuit, at least one grid-connected switch, a voltage-to-ground detector. The inverter circuit is configured to connect to the inverter circuit is configured to connect to the transformer through the at least one grid-connected switch, and the transformer is configured to connect to a power grid. When one grid-connected switch is turned off and turned on, the voltage-to-ground detector detects voltage to grounds of the power conditioning apparatus to obtain a first voltage value and a second voltage value respectively. The controller outputs alarm information for grounding of a neutral wire of the transformer or controls the power conditioning apparatus to stop working when a difference between the second voltage value and the first voltage value falls within a preset voltage range.

A power supply system includes a power conditioning apparatus, a transformer, and a controller. The power conditioning apparatus includes an inverter circuit, at least one grid-connected switch, a voltage-to-ground detector. The inverter circuit is configured to connect to the inverter circuit is configured to connect to the transformer through the at least one grid-connected switch, and the transformer is configured to connect to a power grid. When one grid-connected switch is turned off and turned on, the voltage-to-ground detector detects voltage to grounds of the power conditioning apparatus to obtain a first voltage value and a second voltage value respectively. The controller outputs alarm information for grounding of a neutral wire of the transformer or controls the power conditioning apparatus to stop working when a difference between the second voltage value and the first voltage value falls within a preset voltage range.

A method for protecting an electrical low-voltage circuit includes ascertaining the level of the voltage of the low-voltage circuit in the form of instantaneous voltage values. A change in the current is ascertained over time such that instantaneous current change values are provided. The instantaneous current change values are compared to instantaneous current change threshold values in order to recognize a short circuit in the low-voltage circuit, and if the current change thresholds are exceeded, an electronic interruption unit switches from the low-resistance state to the high-resistance state in order to interrupt the low-voltage current circuit. The process has a trigger time from the short circuit event to the high-resistance state. The trigger time is largely independent of the phase angle. A circuit breaker device for protecting an electrical low-voltage circuit is also provided.

A method for protecting an electrical low-voltage circuit includes ascertaining the level of the voltage of the low-voltage circuit in the form of instantaneous voltage values. A change in the current is ascertained over time such that instantaneous current change values are provided. The instantaneous current change values are compared to instantaneous current change threshold values in order to recognize a short circuit in the low-voltage circuit, and if the current change thresholds are exceeded, an electronic interruption unit switches from the low-resistance state to the high-resistance state in order to interrupt the low-voltage current circuit. The process has a trigger time from the short circuit event to the high-resistance state. The trigger time is largely independent of the phase angle. A circuit breaker device for protecting an electrical low-voltage circuit is also provided.

The present invention relates to a protection device for controlling a power supply circuit for powering a heating arrangement belonging to a heatable clothing garment, where the protection device, first power supply circuit, and clothing garment are adapted to be submerged in a body of water with its user. The protection device is adapted to detect a leaked electric current from the heating arrangement into the body of a user of the clothing garment. The protection device includes a controller adapted to adjust the power supply circuit upon receiving an output signal indicating a leaked current, and a self-test device configured to verify the functionality of the protection device, where the galvanic contact between a testing electrode and the body of the user goes through the body of water.

The present invention relates to a protection device for controlling a power supply circuit for powering a heating arrangement belonging to a heatable clothing garment, where the protection device, first power supply circuit, and clothing garment are adapted to be submerged in a body of water with its user. The protection device is adapted to detect a leaked electric current from the heating arrangement into the body of a user of the clothing garment. The protection device includes a controller adapted to adjust the power supply circuit upon receiving an output signal indicating a leaked current, and a self-test device configured to verify the functionality of the protection device, where the galvanic contact between a testing electrode and the body of the user goes through the body of water.

A safety device for a DC grid includes a voltage measuring device between a potential line and a reference potential line, and a protective circuit for reducing an electric shock caused by Y-capacitors of the electric DC grid. The protective circuit includes a circuit breaker between the respective potential line and the reference potential line. A plurality of tripping criteria are predefined and the first circuit breaker and/or the second circuit breaker can be actuated so as to close exclusively in the event of all predefined tripping criteria being met as determined by the first voltage measuring device and/or by the second voltage measuring device.