scheider electric MiCOM P746 - Page 32

P746/EN TD/G31 Technical Data
(TD) 2-6 MiCOM P746
TD
Three phase overcurrent protection
Accuracy
Pick-up:
∗ Setting ±5% or 20 mA Whichever Is Greater
(WIG)
Drop-off:
∗ 0.95 x Setting ±5%
∗ or 20 mA WIG
Min. trip level of IDMT elements:
∗ 1.05 x Setting ±5%
∗ or 10 mA WIG
IDMT characteristic shape:
∗ ±5% or 40ms WIG
(under reference conditions)*
IEEE reset:
∗ ±5% or 50ms WIG
DT operation:
∗ ±2% or 50ms WIG
DT reset:
∗ Setting ±5% or 20 ms WIG
Characteristic
UK curves:
∗ IEC 60255-3 – 1998
US curves:
∗ IEEE C37.112 – 1996
Earth Fault Protection
Accuracy
Pick-up:
∗ Setting ±5% or 20 mA Whichever Is Greater
(WIG)
Drop-off:
∗ >0.9 x Setting or 20 mA WIG
Min. trip level of IDMT elements:
∗ 1.05 x Setting ±5% or 10 mA WIG
IDMT characteristic shape:
∗ ±5% or 40ms WIG
(under reference conditions)*
IEEE reset:
∗ ±5% or 40ms WIG
DT operation and reset:
∗ ±2% or 50ms WIG
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: <40ms
Programmable scheme logic
Accuracy
Output, dwell and pulse conditioner timers:
∗ Setting ±2% or 50ms whichever is greater
IRIG-B and Real Time Clock
Modulated IRIG-B:
Modulation ratio:
∗ 1/3 or 1/6
Input signal peak-peak amplitude:
∗ 200 mV to 20 V
Input impedance at 1000Hz: 6000 Ω
External clock synchronization:
∗ Conforms to IRIG standard 200-98, format
B
Un-modulated IRIG-B:
Input signal TTL level
Input impedance at dc 10kΩ
External clock synchronization per IRIG
standard 200-98, format B00X.
Performance Accuracy (for modulated and
un-modulated versions)
Real time clock accuracy: < ±2 seconds/day
Measurements
Accuracy
Phase current:
∗ ±1.0% of reading
Phase local current:
∗ ±1.0% of reading
∗ or ±(f-fn)/fn %
Phase remote current
∗ ±1.0% of reading
∗ or ±(f-fn)/fn %
Phase differential current:
∗ ±5.0%
Bias current:
∗ ±5.0%
Frequency:
∗ ±1%
Disturbance records
Accuracy
Waveshape:
∗ Comparable with applied quantities
Magnitude and relative phases:
∗ ±5% of applied quantities
Duration:
∗ ±2%
Trigger position:
∗ ±2% (minimum trigger 100ms)
Reference conditions
Ambient temperature:
∗ 20°C
Frequency Tracking Range
45 to 65Hz
Breaker failure
Accuracy
Reset time < 40ms ±2%
Thresholds: settings ±5%