GE Multilin 850 - Page 25

CHAPTER 1: INTRODUCTION SPECIFICATIONS
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 1–15
NEUTRAL DIRECTIONAL OVERCURRENT (67N)
Directionality: .......................................................Co-existing forward and reverse
Polarizing: ...............................................................Voltage, Current, Dual
Polarizing Voltage:..............................................V_0 or VX
Polarizing Current:..............................................Ig
Operating Current: .............................................I_0
Level Sensing:.......................................................3 x (|I_0| – K x |I_1|), Ig
Restraint, K: ...........................................................0.000 to 0.500 in steps of 0.001
Characteristic Angle:.........................................-90º to 90º in steps of 1°
Limit Angle: ............................................................40º to 90º in steps of 1°, independent for forward and
reverse
Angle Accuracy: ..................................................±2º
Pickup Level:..........................................................0.050 to 30.000 x CT in steps of 0.001 x CT
Dropout Level: ......................................................97 to 98% of Pickup
Operate Time (no direction transition):.....< 16 ms at 3 x Pickup at 60 Hz
< 20 ms at 3 x Pickup at 50 Hz
NEGATIVE SEQUENCE DIRECTIONAL OVERCURRENT (67_2)
Directionality: .......................................................Co-existing forward and reverse
Polarizing: ...............................................................Voltage
Polarizing Voltage:..............................................V_2
Operating Current: .............................................I_2
Level Sensing:.......................................................Negative-sequence: |I_2| – K x |I_1|
Restraint, K: ...........................................................0.000 to 0.500 in steps of 0.001
Characteristic Angle:.........................................0º to 90º in steps of 1°
Limit Angle: ............................................................40º to 90º in steps of 1°, independent for forward and
reverse
Angle Accuracy: ..................................................± 2º
Pickup Level:..........................................................0.050 to 30.000 x CT in steps of 0.001 x CT
Dropout Level: ......................................................97 to 98% of Pickup
Operate Time:.......................................................< 12 ms typical at 3 x Pickup at 60 Hz
< 15 ms typical at 3 x Pickup at 50 Hz
NEUTRAL OVERVOLTAGE (59N)
Operating Parameter:.......................................3V_0 calculated from phase to ground voltages
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
Neutral Overvoltage Curves:.........................Definite time, FlexCurve A,B,C,D
Pickup Time Delay:.............................................0.000 to 6000.000 s in steps of 0.001 s (Definite Time)
Dropout Time Delay: .........................................0.000 to 6000.000 s in steps of 0.001 s (Definite Time)
Operate Time:.......................................................< 25 ms at 1.1 x pickup at 60Hz
< 30 ms at 1.1 x pickup at 50Hz
Curve Timing Accuracy: ..................................at > 1.1 x Pickup: ± 3% of curve delay or ± 1 cycle (whichever
is greater) from pickup to operate
NEGATIVE SEQUENCE OVERVOLTAGE (59_2)
Operating Parameter:.......................................V_2
Pickup Level:..........................................................0.00 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
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
Operate Time:.......................................................< 25 ms at 1.1 x pickup at 60 Hz
< 30 ms at 1.1 x pickup at 50 Hz
Timer Accuracy:.................................................. ± 3% of delay setting or ± ¼ cycle (whichever is greater)
from pickup to operate