摘要 |
The invention concerns a power supply for an arc welder. A main transformer drives a plurality of secondaries. The invention provides a switching and control system that derives fully rectified power from the secondaries, at an adjustable duty cycle, and applies the power to a welding electrode. One advantage to using a plurality of secondaries is that each supplies part of the total electrode current. Thus, the rectification and duty-cycle control can be accomplished by individual devices (such as SCRs) which are distributed over the secondaries. The total cost of the individual devices can be less than the cost of a single device, of equivalent current capacity, used in a single secondary.
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