Trafo-Reaktion auf Voltage Dips, wichtig für die Erfüllung von Medizingeraete Norm EN60601-1-2Transformer Reaction on voltage dipsTransfo reaction sur les "voltage dips", important pour EN 60601-1-2
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fast drop of the voltage on the grid, so called Voltage Dips, could bring transformers into core saturation, depending the phase angle of the dip. Core saturation brings inrush currents and leads to fuse tripping. A TSRL avoids the core saturation and the fuse tripping.  Medical equipment must have been proved with voltage dips. EMV Norm: EN 60601-1-2 . Without a TSRL, they cannot widtstand this test. With a TSRL they pass.

A voltage dip of less than 5 msec. brings the transformer core into saturation, ( when the positive and negative voltage -time areas are no more symmetrically). The following current peak trips the fuse, upper curve is Voltage, lower curve is Current. A TSR can avoid the saturation in the core.
A short voltage dip can drive the iron core from a transformer into saturation, because the positive and negative voltage time Areas are no more symetrically. A TSR can avoid the saturation of the core.
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