4 PERFORMANCE OF CURRENT PROTECTION FUNCTIONS
4.1 TRANSIENT OVERREACH AND OVERSHOOT
Accuracy
Additional tolerance due to increasing X/R ratios +/-5% over the X/R ratio of 1 to 120
Overshoot of overcurrent elements < 40 ms
Disengagement time < 30 ms
4.2 THREE-PHASE OVERCURRENT PROTECTION
Accuracy
IDMT pick-up 1.05 x Setting +/-5%
DT pick-up Setting +/-5% or 20 mA, whichever is greater
Drop-off (IDMT and DT) 0.95 x setting +/-5% or 20 mA, whichever is greater
IDMT operate +/-5% of expected operating time or 40 ms, whichever is greater
IEEE reset +/-5% or 50 ms, whichever is greater
DT operate +/-2% of setting or 50 ms, whichever is greater
DT reset Setting +/-5%
Characteristic UK IEC 60255-3 1998
Characteristic US IEEE C37.112 1996
4.2.1 THREE-PHASE OVERCURRENT DIRECTIONAL PARAMETERS
Accuracy
Directional boundary pickup (RCA +/-90%) +/-2°
Directional boundary hysteresis < 3°
Directional boundary repeatability <1%
Directional voltage pick-up +/-5% or 50 mV, whichever is greater
Directional voltage drop-off 0.95 x setting +/-5% or 50 mV, whichever is greater
Directional voltage repeatability <3%
4.3 VOLTAGE DEPENDENT OVERCURRENT PROTECTION
Accuracy
Voltage threshold pick-up Setting +/- 5%
Voltage threshold drop-off 1.05 x setting +/- 5%
Current threshold pick-up Formula +/- 5%
Current threshold drop-off 0.95 x formula +/- 5%
Note:
These specif
ications apply to VCO only
P64x Chapter 21 - Technical Specifications
P64x-TM-EN-1.3 461
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