2–10 489 GENERATOR MANAGEMENT RELAY – INSTRUCTION MANUAL
CHAPTER 2: INTRODUCTION
OTHER FEATURES
Serial Start/Stop Initiation, Remote Reset (configurable digital input), Test Input
(configurable digital input), Thermal Reset (configurable digital
input), Dual Setpoints, Pre-Trip Data, Event Recorder, Waveform
Memory, Fault Simulation, VT Failure, Trip Counter, Breaker
Failure, Trip Coil Monitor, Generator Running Hours Alarm, IRIG-
B Failure Alarm
OVERCURRENT ALARM
Pickup level: 0.10 to 1.50 × FLA in steps of 0.01 (average phase current)
Time delay: 0.1 to 250.0 s in steps of 0.1
Pickup accuracy: as per phase current inputs
Timing accuracy: ±100 ms or ±0.5% of total time
Elements: Alarm
OVERFREQUENCY
Required voltage: 0.50 to 0.99 × rated voltage in Phase A
Block from online: 0 to 5 sec. in steps of 1
Pickup level: 25.01 to 70.00 in steps of 0.01
Curve shapes: 1 level alarm, 2 level trip definite time
Time delay: 0.1 to 5000.0 s in steps of 0.1
Pickup accuracy: ±0.02 Hz
Timing accuracy: ±150 ms or ±1% of total time at 50Hz and 60Hz; ±300 ms or 2%
of total time at 25Hz
Elements: Trip and Alarm
OVERLOAD / STALL PROTECTION / THERMAL MODEL
Overload curves:
15 Standard Overload Curves, Custom Curve, and Voltage
Dependent Custom Curve (all curves time out against average
phase current)
Curve biasing: Phase Unbalance, Hot/Cold Curve Ratio, Stator RTD, Online
Cooling Rate, Offline Cooling Rate, Line Voltage
Overload pickup: 1.01 to 1.25
Pickup accuracy: as per phase current inputs
Timing accuracy: ±100 ms or ±2% of total time
Elements: Trip and Alarm
OVERVOLTAGE
Pickup level: 1.01 to 1.50 × rated V in steps of 0.01
Curve shapes: Inverse Time, definite time alarm
Time Delay: 0.2 to 120.0 s in steps of 0.1
Pickup accuracy: as per Voltage Inputs
Timing accuracy: ±100 ms or ±0.5% of total time
Elements: Trip and Alarm
PHASE DIFFERENTIAL
Pickup level: 0.05 to 1.00 × CT in steps of 0.01
Curve shape: Dual Slope
Time delay: 0 to 100 cycles in steps of 1
Pickup accuracy: as per phase current inputs
Timing accuracy: +50 ms at 50/60 Hz or ±0.5% total time
Elements: Trip
PHASE OVERCURRENT
Voltage restraint: programmable fixed characteristic
Pickup level: 0.15 to 20.00 × CT in steps of 0.01 of any one phase
Curve shapes: ANSI, IEC, IAC, FlexCurve, Definite Time
Courtesy of NationalSwitchgear.com