Abstract: Device and method for welding a workpiece (2) having a welding torch (3) which can be mechanically coupled by a coupling element (4) to a hose bundle (5) for supplying the welding torch (3) at least with compressed air or with a protective gas, wherein compressed air applied to the coupling element (4) can be diverted by a diverting valve (10) provided in the coupling element (4) for actuating an actuator (7).

Abstract: Burner for a welding apparatus having a non-melting electrode, a wire feed device for a welding wire and a power feed device for introducing an electric heating current into the welding wire that is supplied. The wire feed device can be activated in two directions of advance and an electric voltage applied by the power feed device to the welding wire can be regulated to ignite an igniting arc between the tip of the welding wire and the workpiece.

Abstract: To enable in a circuit arrangement (8) with a transformer with center tap the voltage measurement on the secondary side simply and safely, it is provided that at least two series-connected resistors (R3, R4) are connected between the two outer connections (A1, A2) of the secondary side of the transformer (T) to form a measurement point (P) between the two resistors (R3, R4), and a voltage measurement unit (V) is provided to measure the voltage (UP) between the measurement point (P) and the second output pole (13), which corresponds to the output voltage (UA).

Abstract: A method for establishing welding parameters for a welding process guides a welding torch along a predetermined welding path over the workpiece to be worked and sets welding parameters based on the respective path position for workpiece working. Before establishing the parameters, ideal parameters are determined by test welding processes on test workpieces along test welding paths, with a respective specific test workpiece position and arrangement relative to the gravitational acceleration vector and a specific tangential vector of the test path, and are stored. The parameters at the respective path position are established based on workpiece position and arrangement at the time relative to the welding path gravitational acceleration vector and tangential vector at the time by interpolation of the stored ideal parameter values for the determined positions and arrangements of the test workpieces relative to the gravitational acceleration vector and the specific tangential vectors of the test paths.

Abstract: A short circuit welding method with successive welding cycles with a respective arc phase and short circuit phase includes controlling at least the welding parameters welding current and feed speed of a melting electrode and feeding the electrode toward of a workpiece at a predetermined forward final speed at least during part of the arc phase and away from the workpiece at a predetermined rearward final speed at least during part of the short circuit phase. A device carries out this method. A change in the feed speed and a rearward final speed are predetermined and a welding current is controlled to complete the short circuit phase after reaching the rearward final speed and after 3 ms at the latest and repeat every 8 ms at the latest. The welding parameters are controlled such that the welding cycle duration?8 ms, resulting in a welding frequency?125 Hz.

Abstract: A method for manufacturing a heavy-current transformer with at least one primary winding and at least one secondary winding with surfaces for contacting connects first inner surfaces of the at least one secondary winding with an I-beam of electrically conductive material of the heavy-current transformer with a first soldering material at a first, higher melting temperature, and subsequently at least one contact plate of electrically conductive material is soldered with exterior surfaces of the at least one secondary winding with a second soldering material at a second melting temperature that is lower as compared to the first melting temperature.

Abstract: Device for an energy generation unit of a user's installation, which is connected to an energy supply network and to at least one energy consumption unit of the user's installation and comprises a programmable logic control which controls an internal energy consumption, by the energy consumption units of the user's installation, of the energy generated by the energy generation unit.

Abstract: A plug part releasably connects a liquid-cooled welding torch to a jack part arranged on a hose package, and a connecting device releasably connects a liquid-cooled welding torch to a hose package. In order to provide a connecting device which is suitable for high welding currents and use with hollow shaft robots, each welding current line on the plug part is arranged around a cooling duct, at least in the region of the front face, and the contact area of each welding current line is arranged axially offset from the orifices of the cooling ducts. On the jack part, each welding current line is arranged around a cooling duct, at least in the region of the end piece, and the contact area of each welding current line is arranged axially offset from the orifices of the cooling ducts.

Abstract: In order to set the output voltage of a resonant converter to a desired value by means of a simple additional circuit while the resonant converter is in open circuit operation, it is intended that at least one capacitor each (C1, C2) is connected in parallel to the electrical switching elements (S1, S2) of the secondary side of the resonant converter (1).

Abstract: The invention relates to a heavy-current transformer (12), in particular for a power source (10) in order to provide a welding current of a resistance welding device (1), with at least one primary winding (13) and at least one secondary winding (14) with center tapping, and to a transformer element, a contact plate (29) and a secondary winding (14) for such a heavy-current transformer (12) as well as a method for the manufacturing thereof. For reduction of losses and improvement of efficiency, at least four contacts (20, 21, 22, 23) are provided to form a multi-point contacting, said contacts (20, 21, 22, 23) being formed by four contact faces within which the at least one primary winding (13) and the at least one secondary winding (14) are arranged in a series/parallel connection.

Abstract: A resistance welding device includes a power source in order to provide a welding current for welding workpieces, a welding gun with two gun arms having one electrode each in order to impress the welding current into the workpieces. The power source includes a heavy-current transformer with at least one primary winding and at least one secondary winding with center tapping, a synchronous rectifier connected with the secondary winding and including circuit elements, and a circuit for actuating the circuit elements of the synchronous rectifier. For reduction of losses and improvement of efficiency, the power source is arranged at the welding gun and the power source includes at least four contacts forming a multi-point contacting, wherein two first contacts of one polarity are connected to one gun arm and two additional contacts of opposite polarity are connected to the other gun arm.

Abstract: A heat sink for cooling electronic power components arranged in a housing includes a cooling element having cooling fins arranged on a base surface, and a fan for intake of ambient air and for delivering the ambient air via the cooling fins of the cooling element, the cooling element having a recess, in which the fan is arranged spaced apart from the base surface. The fan includes a housing ring on the side facing away from the base surface of the cooling element, an intermediate space being formed between the bottom edge of the housing ring and the base surface of the cooling element. The fan is an axial fan, so that the ambient air taken in impinges upon the base surface of the cooling element, is deflected by essentially 90 degrees and guided through the intermediate space laterally between the cooling fins to the outside.

Abstract: To enable in a circuit arrangement (8) with a transformer with center tap the voltage measurement on the secondary side simply and safely, it is provided that at least two series-connected resistors (R3, R4) are connected between the two outer connections (A1, A2) of the secondary side of the transformer (T) to form a measurement point (P) between the two resistors (R3, R4), and a voltage measurement unit (V) is provided to measure the voltage (UP) between the measurement point (P) and the second output pole (13), which corresponds to the output voltage (UA).

Abstract: A circuit arrangement for controlling a transistor with an insulated gate, a gate driver for generating a driver signal, and a capacitor parallel to the gate-source path of the transistor, wherein the gate driver is designed for generating a driver signal greater than or equal to zero volts, an inductor is provided for forming a resonant circuit with the capacitor, and a switching element is provided in the resonant circuit, which is designed for interrupting the resonant circuit after recharging the capacitor. The part of the circuit arrangement downstream of the gate driver is designed for exclusive voltage supply using the driver signal of the gate driver, and the switching element is formed by an additional transistor, a first freewheeling diode is arranged parallel to the switching element, and the inductor of the resonant circuit is arranged between the additional transistor and the gate of the transistor.

Abstract: A device for releasable fixed holding of a welding wire in a welding wire guide is described. This device is characterized in that the welding wire guide includes a cage for radially displaceable braking bodies, wherein a locking cone surrounds the braking bodies, and that, of the two cooperating functional elements, formed on the one hand by the welding wire guide and on the other hand by the locking cone, one is mounted in a non-displaceable manner in a holder and the other is mounted to be axially displaceable against a spring force with respect to the non-displaceable functional element.

Abstract: The invention relates to an inverter (1) for converting a DC voltage (UDC) into an AC voltage (UAC), in particular a photovoltaic inverter for high power densities, in particular power densities of 250 W/dm3 to 500 W/dm3, having at least one DC input (5), an AC output (11), a heat sink (20), a printed circuit board (32), a DC disconnector (7), a DC-DC converter (8), an intermediate circuit (9), a DC-AC converter (10) and a housing (14) with a front cover (15) and a basic shell (16).

Abstract: Power transmission system (1) for power transmission of electric power (P) from a power source (2A) to a power sink (4A) which is connected to the power source (2A) via a power transfer cable (3), wherein the power source (2A) has a first pole with a first electric potential, which is connected via parallel current lines of a first conducting pair of the power transfer cable (3) to a first pole of the power sink (4A), and a second pole with a second electric potential, which is connected via further parallel current lines of a second conducting pair of the power transfer cable (3) to a second pole of the power sink (4A), wherein, during the power transmission via the current lines, a user data signal can be transmitted between the power source (2A) and the power sink (4A) via at least one conducting pair with current lines of the same electric potential, uninfluenced by the power transmission.

Abstract: The invention relates to a method for testing the strings (3) of a photovoltaic system, and also to a photovoltaic inverter (1) for carrying out this method.

Abstract: A circuit arrangement for controlling a transistor with an insulated gate, a gate driver for generating a driver signal, and a capacitor parallel to the gate-source path of the transistor, wherein the gate driver is designed for generating a driver signal greater than or equal to zero volts, an inductor is provided for forming a resonant circuit with the capacitor, and a switching element is provided in the resonant circuit, which is designed for interrupting the resonant circuit after recharging the capacitor. The part of the circuit arrangement downstream of the gate driver is designed for exclusive voltage supply using the driver signal of the gate driver, and the switching element is formed by an additional transistor, a first freewheeling diode is arranged parallel to the switching element, and the inductor of the resonant circuit is arranged between the additional transistor and the gate of the transistor.