STATISCH AUSLOESBARER UEBERLASTSCHALTER MIT SELBSTTAETIGER SCHALTKREIS-TRIMMUNG

Electronic trip units employed within static trip circuit breakers are individually calibrated and automatically adjusted to ensure that the trip transfer characteristics are within specification requirements. A trimming network within the trip unit circuit contains a plurality of parallel resistors each separately connected within the circuit by means of a fusible link. Test input and output values are compared to idealized values that are binary-weighted within a look-up table in the test equipment computer. The percent correction required is determined and the appropriate links are interrupted to provide ideal trip response.