2 * Is PHASE sec sec. EXP ACT PHASE-R PHASE-Y PHASE-B EARTH FAULT PICK UP / RESET RESULT: In=0.13In CURVE:NI PICK UP MEASURED MEASURED PHASE PICK UP(A) SETTING DROP OFF (A) 0.13 PHASE R – Note: pick up error =±5% Drop off Level = >95% of pick up EARTH FAULT CHARACTERISTIC: Normal inverse Is =0.2In Tm : 0.3 T = (0.14*Tm) / ( (I/I s) ^ 0.02 1 )) sec. – 2 * Is PHASE sec sec. EXP ACT PHASE-R lV over current and earth fault: OVER CURRENT PICK UP / RESET RESULT: In= 1.23 In CURVE:NI PICK UP MEASURED MEASURED PHASE PICK UP(A) SETTING DROP OFF (A) 1.23 PHASE R – 1.23 PHASE –Y 1.23 PHASE - B
PHASE 2 * Is EXP sec ACT sec. PHASE-R PHASE-Y PHASE-B EARTH FAULT PICK UP / RESET RESULT: In=0.13In CURVE:NI PHASE PICK UP SETTING MEASURED PICK UP(A) MEASURED DROP OFF (A) PHASE – R 0.13 Note: pick up error =±5% Drop off Level = >95% of pick up EARTH FAULT CHARACTERISTIC: Normal inverse Is =0.2In Tm : 0.3 T = (0.14*Tm) / ( (I/I s) ^ 0.02 – 1 )) sec. PHASE 2 * Is EXP sec ACT sec. PHASE-R lV over current and earth fault: OVER CURRENT PICK UP / RESET RESULT: In= 1.23 In CURVE:NI PHASE PICK UP SETTING MEASURED PICK UP(A) MEASURED DROP OFF (A) PHASE – R 1.23 PHASE –Y 1.23 PHASE - B 1.23
transformer_diff_-_p643.docx