Computer Weld Technology's Automatic Torch Control (ATC II™) is a compact, lightweight, weld torch manipulation control system comprised of the microcontroller based Automatic Torch Control and a stepper motor driven Linear Slide Assembly (LSA). This system is capable of providing independent control of all torch movements in the vertical plane. Employing patented "Thru-Arc™" tracking technology, the system provides automatic torch height control for both GTAW, PAW and GMAW applications.

The ATC II™ provides automatic torch height and two modes of Torch Height Control. Mode 4 provides Torch Height Control using Arc Voltage Control (AVC). Mode 5 provides torch height control using Arc Current Control (ACC). The entire torch tracking information is derived from the welding arc. The arc voltage and welding current is measured with an external voltage probe and Hall-Effect clamp on current sensor provided with the system. The two modes allow the ATC to be used for GTAW, PAW and GMAW applications. The ATC II™ also provides a Touch-Retract function for accurate torch positioning at arc start for GTAW applications.

The ATC II™ provides a user definable 50 sequence Programmable Logic Controller (PLC) with four 24 vdc inputs and two N.O. relay contacts. Using the ATC II™ PLC, the user can define how the ATC II™ will interface to an external control system. It can also be used to provide external system control and a simple power source interface.

The ATC II™ Control provides the necessary control signals to the stepper motor powered slide. At power-up the slide is driven to the upper limit then the torch will be located to a user defined start location. The front panel controls allow the user to define the starting position, tracking reference values and to Enable/Disable the tracking functions. The ATC II™ will automatically detect a valid arc active condition and will perform the selected torch height tracking function. During the weld the user can Enable/Disable the Torch Tracking function. A RS-232 serial port is provided for off-line PLC programming and ATC II™ control system configuration.