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Understanding Mid-Frequency Inverter Feedback Modes

From Miyachi Unitek Corporation
 

 

Closed-loop feedback control is a key part of inverter technology. This paper outlines commonly available feedback modes, and describes best practice implementation of each. The common feedback modes provided on inverter weld controls are Primary Limit, Primary RMS Constant Current, Secondary RMS Constant Current, Secondary RMS Constant Power, and Fixed Pulse.

Primary Limit - This is a weld current measurement on the primary side of the weld transformer. The peak current is measured with a hall-effect sensor built-in to the weld control.

Primary RMS Constant Current - This mode uses the same feedback method as Primary Limit with the feedback algorithm using RMS values.

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