GE 489 Instruction Manual page 10

1.1 OVERVIEW
Table 1–1: TRIP AND ALARM PROTECTION FEATURES
1
TRIP PROTECTION
7 assignable digital inputs:
general input, sequential trip (low forward power or reverse
power), field-breaker discrepancy, and tachometer
offline overcurrent (protection during startup)
inadvertent energization
phase overcurrent with voltage restraint
negative sequence overcurrent
ground overcurrent
percentage phase differential
ground directional
high-set phase overcurrent
undervoltage
overvoltage
volts/hertz
voltage phase reversal
underfrequency (two step)
overfrequency (two step)
neutral overvoltage (fundamental)
neutral undervoltage (3rd harmonic)
loss of excitation (2 impedance circles)
distance element (2 zones of protection)
reactive power (kvar) for loss of field
reverse power for anti-motoring
low forward power
RTDs: stator, bearing, ambient, other
thermal overload
analog inputs 1 to 4
electrical lockout
Power metering is a standard feature in the 489. The table below outlines the metered parameters available to the operator
or plant engineer either through the front panel or communications ports. The 489 is equipped with three fully functional and
independent communications ports. The front panel RS232 port may be used for setpoint programming, local interrogation
or control, and firmware upgrades. The computer RS485 port may be connected to a PLC, DCS, or PC based interface
software. The auxiliary RS485 port may be used for redundancy or simultaneous interrogation and/or control from a second
PLC, DCS, or PC program. There are also four 4 to 20 mA transducer outputs that may be assigned to any measured
parameter. The range of these outputs is scalable. Additional features are outlined below.
Table 1–2: METERING AND ADDITIONAL FEATURES
METERING
voltage (phasors)
current (phasors) and amps demand
real power, MW demand, MWh
apparent power and MVA demand
reactive power, Mvar demand, Mvarh positive/negative
frequency
power factor
RTD
speed in RPM with a key phasor Input
user programmable analog inputs
1-2
ALARM PROTECTION
7 assignable digital inputs: general input and tachometer
overload
negative sequence
ground overcurrent
ground directional
undervoltage
overvoltage
volts/hertz
underfrequency
overfrequency
neutral overvoltage (fundamental)
neutral undervoltage (3rd harmonic)
reactive power (kvar)
reverse power
low forward power
RTD: stator, bearing, ambient, other
short/low RTD
open RTD
thermal overload
trip counter
breaker failure
trip coil monitor
VT fuse failure
demand: current, MW, Mvar, MVA
generator running hours
analog inputs 1 to 4
service (self-test failures)
IRIG-B failure
ADDITIONAL FEATURES
drawout case
(for ease of maintenance and testing)
breaker failure
trip coil supervision
VT fuse failure
simulation
flash memory for easy firmware updates
489 Generator Management Relay
1 INTRODUCTION
GE Power Management