In one embodiment, a welding system includes an engine and a generator connected to the engine. The welding system also includes a power source having a controller. The power source is electrically connected to a welding electrode and a workpiece. The controller determines that an electrical load on the welding system has not been detected for a first time period while the engine is running, determines that a coolant temperature meets a minimum requirement, commands shutdown of the engine when the load has not been detected for the first time period and when the coolant temperature meets the minimum requirement, determines that the load has been detected (due to a single contact of the welding electrode to the workpiece) during a second time period after the engine has been shut down, and commands restart of the engine when the load has been detected during the second time period.

Disclosed is an arc welding control method of controlling a welding current in short-circuit arc welding of feeding a welding wire toward a base metal and alternating a short-circuit state and an arc state. The arc welding control method includes: executing, in the short-circuit state, a first increase in the welding current with a first slope, a first decrease in the welding current to a first bottom value after executing the first increase, a second increase in the welding current with a second slope after executing the first decrease, and a second decrease in the welding current to a second bottom value that is smaller than the first bottom value after executing the second increase to shift a state to the arc state.

Method for compensating an interfering influence on a welding current, provided by a welding power source (4) for welding a workpiece (3), from another welding power source (4′), comprising the steps of: (a) providing (SA) a compensation voltage (U.sub.Komp), which is calculated on the basis of a welding current progression provided by the other welding power source (4′); (b) subtracting (SB) the compensation voltage (U.sub.Komp) from a measured voltage (U.sub.Mess), measured by a voltage measurement unit (8) of the welding power source (4), so as to determine a corrected measured voltage (U′.sub.Mess); and (c) regulating (SC) the welding current generated by the welding power source (4) as a function of the corrected measured voltage (U′.sub.Mess).

A technique for dynamically adjusting an output voltage for a welding or cutting operation is provided. The technique allows for varying output voltage at the welding or cutting torch by manipulating the duty cycles of two forward converter circuits. The present disclosure provides methods and systems for increasing synchronized duty cycles in a pair of forward converter circuits in response to increasing output voltage demand then changing a phase shift between the duty cycles in response to further increases in output voltage demand. The present disclosure provides a controller designed to receive input signals and generate output pulse width modulation signals that control the duty cycle width and phase shift of the outputs of the forward converter circuits in response to these signals. Methods of accommodating for the time needed for the transformer core to reset via leading edge or lagging edge compensation are provided.

The invention relates to an arc welding method using a consumable welding wire (1), wherein in successive welding cycles (SZ) during a welding process (P.sub.i) a certain welding current (I(t)) is applied to the welding wire (1) and the welding wire is moved with a certain wire conveying speed (v(t)) towards a workpiece (2) to be processed. The aim of the invention is to further improve the stability of the welding method. The aim is achieved, according to the invention, in that in the event of a change of the welding process (P.sub.1) to a welding process (P.sub.2) with an increased mean wire conveying speed (v.sub.mean) during a welding cycle (SZ) and/or with an increased mean welding current (I.sub.mean) during a welding cycle (SZ), a lowering phase (AP) is initiated, wherein in the lowering phase (AP) the welding current (I.sub.A(t)) is lowered for a specified duration (Δt.sub.A).

This welding control device which controls a welding condition when arc welding is performed on a groove having a root gap, comprises: a first detection means for detecting, from a captured image of a fused section formed in the groove, the position of the tip of the fused section with respect to a direction in which the welding progresses; a second detection means for detecting the position of an end of a to-be-welded object for defining the root gap; a determination means for determining the relationship between the position of the end and the position of the tip of the fused section; and a control means for controlling the welding condition according to the determination result.

A contact tip assembly with a preheating tip comprises a welding-type power source configured to provide welding-type current to a welding-type circuit, the welding-type circuit comprising a welding-type electrode and a first contact tip of a welding torch. The assembly also includes an electrode preheating circuit configured to provide preheating current through a portion of the welding-type electrode via a second contact tip of the welding torch, and a voltage sense circuit to monitor a voltage drop across the two contact tips, and the electrode preheating circuit adjusts at least one of the first current or the preheating current based on the voltage drop.

A method and apparatus for providing welding type power includes a phase shifted double forward converter having a first and second converter with a controller and an output rectifier. The output rectifier has at least one cathode current path that creates a cathode magnetic field when current flows in the cathode current path. The output rectifier also has at least one anode current path that creates an anode magnetic field when current flows in the anode current path. The cathode current path is disposed and oriented and the anode current path is disposed and oriented such that the cathode magnetic field acts to at least partially cancel the anode magnetic field.

A dynamic handheld torch head for a plasma cutting or welding operation is disclosed. The system for controlling the handheld torch includes a handle and a torch head disposed at the handle; a power supply; and a processor disposed at the power supply and/or the torch. The power supply may be configured to provide power to the torch to initiate a processing operation. The processor may be configured to determine an arc voltage between the torch head and a workpiece during the processing operation, and determine a distance between the torch head the workpiece based on the determined arc voltage.

An example welding type system includes: a welding power circuit having a control input and a welding type power output; a feedback circuit configured to provide feedback regarding the welding type power output or a weld produced using the welding type power output; and a controller connected to the feedback circuit, wherein the controller includes a parameter setting module and a process selection module, the process selection module configured to automatically select a welding process from a plurality of welding processes based on the feedback from the feedback circuit or one or more welding parameters set by the parameter setting module.