GE Multilin 850 Instruction Manual page 29

CHAPTER 1: INTRODUCTION
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
SENSITIVE GROUND DIRECTIONAL OVERCURRENT (67SG)
Directionality: .......................................................Co-existing forward and reverse
Polarizing: ...............................................................Voltage, Current, Dual
Polarizing Voltage:..............................................V_0 or VX
Polarizing Current: ..............................................Ig
Operating Current: .............................................Isg
Level Sensing: .......................................................Ig, Isg
Characteristic Angle:.........................................-90º to 90º in steps of 1°
Limit Angle: ............................................................40º to 90º in steps of 1°, independent for forward and
Angle Accuracy: ..................................................± 2º
Pickup Level:..........................................................0.005 to 3.000 x CT in steps of 0.001 x CT
Dropout Level: ......................................................97 to 98%
Operate Time (no direction transition):.....< 12 ms typical at 3 × Pickup at 60 Hz
SOTF (SWITCH ON TO FAULT)
Number of Elements: ........................................6 (3 per Breaker)
Pickup Threshold:................................................0.050 to 10.000 pu of CT in steps of 0.001
Pickup Level Accuracy: ....................................0.1 to 2.0 x CT rating: ±0.5% of reading or ±1% of rated
Pickup Level:..........................................................0.05 to 1.00 x VT in steps of 0.01
Level Accuracy:....................................................±0.5% of reading from 10 to 240 V
Pickup Delay: ........................................................0.000 to 600.000 s in steps of 0.01
Time Accuracy:....................................................±3% or ±35 ms, whichever is greater
Operate Time:.......................................................<10 ms @ 60Hz
TIMED UNDERVOLTAGE - TIMED UV (27T)
Operating Parameter:.......................................[VA, VB, VC] or [VA, VB, VC] (Phasor)
Minimum Voltage:...............................................0.00 to 1.50 (VT) in steps of 0.01 VT
Pickup Level:..........................................................0.00 to 1.50 (VT) in steps of 0.01 VT
Dropout Level: ......................................................102.0% to 150.0% of PKP in steps of 0.1% PKP
Level Accuracy:....................................................±0.5% of reading from 10 to 240 V
Phases required for operation:.....................Any one, Any two, All three
Curve Limit:............................................................0.00 to 1.50 (VT) in steps of 0.01 VT
Curve Time:............................................................0.000 – 600000.000 s in steps of 0.001s
Dropout Time Delay: .........................................0.000 – 600000.000 s in steps of 0.001s
Pickup Accuracy:.................................................Per phase voltage input channel error
Dropout Accuracy: .............................................Per phase voltage input channel error
Curve Timing Accuracy: ..................................at < 0.90 x pickup: ± 3.5% of operate time or ± ½ cycle
THERMAL OVERLOAD (49)
Operating Parameter:.......................................RMS current
Pickup Level:..........................................................0.050 to 30.000 x CT in steps of 0.001 x CT
Alarm Level: ...........................................................70.0 to 110.0% in steps 0.1%
Heat Time Constant (τ ): .................................3.0 to 600.0 min in steps of 0.1 min
H
Cool Time Constant (τ ): ..................................1.00 to 6.00 x τ
C
Current Level Accuracy: ..................................For 0.1 to 2.0 x CT: ± 0.5% of reading or ± 0.4% of rated
Operate Time:.......................................................< 45 ms at 60 Hz (from 0 to 120 x pickup)
reverse
< 15 ms typical at 3 × Pickup at 50 Hz
(whichever is greater)
> 2.0 x CT rating: ±1.5% of reading
(whichever is greater) from pickup to operate
in steps of 0.01 x τ
H
(whichever is greater)
For > 2.0 x CT: ± 1.5% of reading
< 50 ms at 50 Hz (from 0 to 120 x pickup)
SPECIFICATIONS
H
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