Abstract: Summary The method of measuring welding current in fast is need. On the basis of theoretical analysis of the functions of the welding process, it has been found that a simple relation between the welding current effective value and average value is exist, take no account to the power factor of the system.
In this paper, the design principle of softwave of digital approach using microcomputer is discussed in detail. It has been demonstrated practically that in a few microsecond, the welder current effective value within a cycle or several cycles can be measured precisely.