GE 339 Instruction Manual page 21

CHAPTER 1: INTRODUCTION
339 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUND FAULT/SENSITIVE GROUND FAULT (CBCT) (50G/SG)
Pickup Level:.......................................................... 0.03 to 1.00 x CT in steps of 0.01 x CT
Dropout Level: ...................................................... Pickup - 0.01 x CT
Alarm Time Delay on Run:.............................. 0.00 to 60.00 s in steps of 0.01 s
Alarm Time Delay on Start:............................ 0.00 to 60.00 s in steps of 0.01 s
Trip Time Delay on Run: .................................. 0.00 to 5.00 s in steps of 0.01 s
Trip Time Delay on Start:................................. 0.00 to 10.00 s in steps of 0.01 s
Pickup Accuracy:................................................. as per ground current inputs
Operate Time:....................................................... <30 ms @ 60Hz (I > 2.0 x PKP), 0 ms time delay
Timing Accuracy:................................................ 0 to 1 cycle
Elements: ................................................................ Trip and Alarm
THERMAL PROTECTION (49)
Locked Rotor Current:....................................... 2.0 to 11.0 x FLA in steps of 0.1 x FLA
Safe Stall Time:..................................................... 1.0 to 600.0 s in steps of 0.1 s
Curve Multiplier:................................................... 1 to 15 in steps of 1
Pickup Level:.......................................................... 1.01 to 1.25 x FLA in steps of 0.01 x FLA
Curve Biasing:....................................................... Phase unbalance
TCU Update Rate: ............................................... 3 cycles
Pickup Accuracy:................................................. per phase current inputs
Timing Accuracy:................................................ ±200 ms or ±2% of total time
Elements: ................................................................ Trip and Alarm
PHASE/POSITIVE SEQUENCE UNDERVOLTAGE (27P, 27_1)
Minimum Voltage:............................................... Programmable from 0.00 to 1.25 x VT in steps of 0.01
Pickup Level:.......................................................... 0.00 to 1.25 x VT in steps of 0.01 x VT
Dropout Level: ...................................................... 102% of pickup for pickup > 0.1 x VT
Curve: ....................................................................... Definite Time, Inverse Time
Time Delay:............................................................ 0.00 to 600.00 s in steps of 0.01
Operate Time:....................................................... Time delay ±30 ms @ 60 Hz (V < 0.85 x PKP)
Time Delay Accuracy: ...................................... ±3% of expected time, or 1 cycle, whichever is greater
Level Accuracy:.................................................... Per voltage input
UNDERPOWER (37)
Pickup Level:.......................................................... 1 to 100% Hz MNR in steps of 1%
Dropout Level: ...................................................... 102% of pickup for pickup > 50
Time Delay:............................................................ 1.0 to 60.0 s in steps of 0.1
Pickup Accuracy:................................................. as per power monitoring specification
Timing Accuracy:................................................ ±0.5 s or ±0.5% of total time
Elements: ................................................................ Trip and Alarm
NEGATIVE SEQUENCE/PHASE OVERVOLTAGE (59_2, 59P)
Pickup Level:.......................................................... 0.00 to 1.25 x VT in steps of 0.01
Dropout Level: ...................................................... 98% of pickup for pickup > 0.1 x VT
Time Delay:............................................................ 0.00 to 600.00 s in steps of 0.01
Operate Time:....................................................... Time delay ±30 ms @ 60 Hz (V >1.1 x PKP)
Time Delay Accuracy: ...................................... ±3% of expected time, or 1 cycle, whichever is greater
Level Accuracy:.................................................... Per voltage input
0.50 to 15.00 A in steps of 0.01 A (CBCT)
Pickup - 0.03 x CT (CBCT)
<35 ms @ 50Hz (I > 2.0 x PKP), 0 ms time delay
Hot/cold biasing
Stator RTD biasing
Exponential Running and Stopped Cooling Rates
Pickup + 0.02 x VT for pickup < 0.1 x VT
Time delay ±40 ms @ 50 Hz (V < 0.85 x PKP)
Pickup + 1 for pickup ≤ 50
Pickup - 0.02 x VT for pickup < 0.1 x VT
Time delay ±40 ms @ 50 Hz (V > 1.1 x PKP)
SPECIFICATIONS
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