Funktion vom TSRL und TSRLF.Function of TSRL and TSRLF.fonction du TSRL ou du TSRLF
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The Function of TSR switch on procedure for single phase transformers is based on a controlled premagnetizing, this is patented in some countries.

TSR-Function: Premagnetising of the Transformer with unipolar Voltage Time impulses until the remanence reaches the max. point. Then full switch on, then close the bypassrelay contact.
The TSR premagnetise the transformer before switch on. He avoids inrush currents.
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