GE 889 - Page 27

CHAPTER 1: INTRODUCTION SPECIFICATIONS
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 1–17
NEGATIVE SEQUENCE INSTANTANEOUS OVERCURRENT (50_2)
Current:....................................................................I_2 Fundamental Phasor Magnitude
Pickup Level:..........................................................0.050 to 30.000 x CT in steps of 0.001 x CT
Dropout Level: ......................................................97 to 98% of Pickup
Level Accuracy:....................................................For 0.1 to 2.0 x CT: ±0.5% of reading or ± 0.4% of rated,
whichever is greater
For > 2.0 x CT: ± 1.5% of reading
Pickup Time Delay:.............................................0.000 to 6000.000 s in steps of 0.001 s
Dropout Time Delay:.........................................0.000 to 6000.000 s in steps of 0.001 s
Overreach:..............................................................< 2%
Operate Time:.......................................................< 12 ms typical at 3 x Pickup at 60 Hz
< 15 ms typical at 3 x Pickup at 50 Hz
Timer Accuracy: ..................................................±3% of delay setting or ± ¼ cycle (whichever is greater) from
pickup to operate
PHASE REVERSAL
Phase Reversal Condition: ..............................V
2
/V
1
=100% when phase to phase voltages are greater than
50% of VT
Configuration:.......................................................ABC or ACB phase rotation
Pickup/Dropout Time Delay: .........................0.00 to 180.00 s in steps of 0.01 s
Timer Accuracy: ..................................................±3% of delay setting or ±1% cycle (whichever is greater)
from pickup to operate
PHASE UNDERVOLTAGE (27P)
Voltage:....................................................................Fundamental Phasor Magnitude
Minimum Voltage:...............................................0.00 to 1.50 x VT in steps of 0.01 x VT
Pickup Level:..........................................................0.00 to 1.50 x VT in steps of 0.01 x VT
Dropout Level: ......................................................102 to 103% of Pickup
Level Accuracy:....................................................±0.5% of reading from 10 to 208 V
Phases Required for Operation: ...................Any one, Any two, All three
Undervoltage Curves: .......................................Definite Time, GE IAV Inverse Time or FlexCurves A/B/C/D
Pickup Time Delay:.............................................0.000 to 6000.000 s in steps of 0.001s
Operate Time:.......................................................< 20 ms at 0.90 x pickup at 60 Hz
< 25 ms at 0.90 x pickup at 50 Hz
Curve Timing Accuracy: ..................................at < 0.90 x pickup: ± 3.5% of curve delay or ± ½ cycle
(whichever is greater) from pickup to operate
PHASE OVERVOLTAGE (59P)
Voltage:....................................................................Fundamental Phasor Magnitude
Pickup Level:..........................................................0.02 to 3.00 x VT in steps of 0.01 x VT
Dropout Level: ......................................................97 to 98% of Pickup
Level Accuracy:....................................................±0.5% of reading from 10 to 208 V
Phases Required for Operation: ...................Any one, Any two, All three
Pickup Time Delay:.............................................0.000 to 6000.000 s in steps of 0.001s (Definite Time)
Dropout Time Delay:.........................................0.000 to 6000.000 s in steps of 0.001s (Definite Time)
Pickup Accuracy:.................................................Per phase voltage input channel error
Operate Time:.......................................................< 25 ms at 1.1 x pickup at 60Hz
< 30 ms at 1.1 x pickup at 50Hz
Timer Accuracy: ..................................................± 3% of delay setting or ± ¼ cycle (whichever is greater)
from pickup to operate