Abstract: A method and apparatus for preboot file and information transfer between workstations and other workstations or workstations and servers on local area networks. During a workstation boot sequence, the various components of the workstation and network operating system are loaded and executed. Since all control of the workstation after the boot sequence is passed to the workstation operating system, any management tasks performed after boot must be performed by application programs running on the workstation. The present invention overcomes problems created by using such application programs to perform management tasks by providing a hardware component, for example a ROM or PROM containing appropriate programming placed in the usually unused boot ROM socket of a LAN card installed in the individual workstations, or a chip including a PROM or ROM built onto the motherboard or system board of the individual workstations.

Abstract: A rack mountable weld controller for use as a plug in card within a rack of a programmable logical controller (PLC) system. All signals between the PLC and the weld controller are through the backplane of the rack in which the weld controller is installed. In this manner, the large number of signals which are needed to operate the weld controller may be passed through the backplane rather than over a set of cables connecting the weld controller to an input card and output card which are themselves plugged into a backplane slot.

Abstract: The present invention is directed to a programmable logical controller (PLC) system incorporating a universal input controller card, a universal output controller card, and a symmetrical current mirror fuse blown detector circuit. The universal input controller card is capable of tracking input voltages from 12 to 240 volts, AC or DC. The universal output controller card is capable of outputting output voltages ranging from 12 to 120 volts, AC or DC with no significant leakage current and no load resistors. The current mirror fuse blown detector circuit detects blown fuses in each output channel of the output controller card.