The purpose of this invention is a device for generating voltage dips of a depth of up to 100% with adjustable variation switches and at as many levels of depth as wished, for connection in a wind farm or electricity generating system between the electrical energy evacuation line produced by the generators of the electrical installation in general or wind generation in particular and the system of electrical energy generation or wind turbine under test, where the voltage dip generator device controls and regulates the short circuit power detected by the electrical energy generating machinery or the wind turbine to be tested for voltage values exceeding 500 V and power exceeding 100 kW.

A detachable tip, utilized with a power adapter, includes a memory, a receiver, and a transmitter. The memory stores a character string, the character string identifying whether an approved power adapter is coupled to the detachable tip. The receiver receives an identification request from an electronic device. In response to the identification request, a transmitter transmits the stored character string to the electronic device. A controller may extract the character string from the memory and send the character string to the transmitter. Instead of a character string, the memory may store a value, which is representative of a maximum power output available. A detachable tip may include an input connector and an output connector. The input connector receives a value from the power adapter, the value being representative of a maximum power available from the power adapter. The output connector passes through the value to the electronic device.

A display mode switching function unit recognises one-click or double-click of an operating dial (4) and switches a menu mode display image (30), an [H Scroll] mode display image (32), a [V Scroll] display image (33) and a [Zoom] mode display image (34). When the [H Scroll] mode display image (32) is displayed, an image display control function unit recognises clockwise or counterclockwise rotation of the operating dial (4) and causes a map image to be scrolled right or left. When the [V Scroll] mode display image is displayed, the image display control function unit recognises clockwise or counterclockwise rotation of the operating dial (4) and causes a map image to be scrolled up or down. When the [Zoom] mode display image (34) is displayed, the image display control function unit recognises clockwise or counterclockwise rotation of the operating dial (4) and causes a map image to be displayed on an enlarged or reduced scale. Thus, display control of a displayed image is carried out without providing additional operating keys.

An inductor current-sensing circuit for measuring a current in an inductor includes (a) a first RC network coupled between a first terminal of the inductor and a reference voltage source; and (b) a second RC network coupled between a second terminal of the inductor and the reference voltage source. The first RC network and the second RC network each have a time constant substantially equal to the ratio between the inductance and the DC resistance of the inductor. The inductor which current is being measured may be a primary inductor of a four-switch buck boost converter receiving an input voltage and providing an output voltage.

A tip for transferring DC power generated by an adapter to an electronic device, the tip comprising: an input connector which is detachably mateable to a connector which is electrically coupled to the DC power generated by the adapter; an output connector which is detachably mateable to the electronic device; a plurality of conductors to transfer the DC power from the input connector to the output connector to provide the DC power to the electronic device; and power indication circuitry to transmit to the electronic device via the output connector a power output indication signal representative of an amount of power available to be supplied to the electronic device by the adapter.