3 PERFORMANCE OF CURRENT PROTECTION FUNCTIONS
3.1 TRANSIENT OVERREACH AND OVERSHOOT
Additional tolerance due to increasing X/R ratios +/-5% over the X/R ratio of 1 to 90
Overshoot of overcurrent elements < 30 ms
3.2 PHASE OVERCURRENT PROTECTION
Accuracy
IDMT pick-up 1.05 x Setting +/-5%
DT pick-up Setting +/-5%
Drop-off (IDMT and DT) 0.98 x setting +/-5%
IDMT operate +/-5% of expected operating time or 40 ms, whichever is greater*
IEEE reset +/-5% or 40 ms, whichever is greater
DT operate +/-2% of setting or 40 ms, whichever is greater
DT reset Setting +/-5%
Repeatability <5%
Characteristic UK IEC 60255-3 1998
Characteristic US IEEE C37.112 1996
Note:
*Refer
ence conditions: TMS = 1, TD = 7, I> = 1A, operating range = 2-20In
3.2.1 PHASE OVERCURRENT DIRECTIONAL PARAMETERS
Accuracy
Directional boundary pickup (RCA +/-90%) +/-2°
Directional boundary hysteresis < 2°
Directional boundary repeatability <2%
3.3 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 specifications apply t
o both VCO and VRO
Chapter 23 - Technical Specifications P14x
536 P14xEd1-TM-EN-1
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