GE 889 Instruction Manual page 13

CHAPTER 1: INTRODUCTION
52
Slot K – Ground
(Sensitive or 50:0.025)
Slot J1 – Ph Bank
G
Slot K1 – Ph Bank
Slot J –Ground
R
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL
current and voltage phasors, such that the resulting values have no harmonic
components. RMS (root mean square) values are calculated from one cycle of samples
prior to filtering.
Protection Elements
All voltage, current and frequency protection elements are processed eight times every
cycle to determine if a pickup has occurred or a timer has expired. The voltage and current
protection elements use RMS current/voltage, or the magnitude of the phasor.
Figure 1-1: Single Line Diagram
Slot K2 – Ph Bank or Vx
Close
Trip
Monitoring
Slot J2 – Ph Bank
50SG 51SG 67SG
LIGHT
AFP
RTD
76
dcmA
EX
39
dcmA
87G
50G
87GD
R
Slot J – Vx
DESCRIPTION OF THE 889 GENERATOR PROTECTION SYSTEM
889 Generator Protection System
27P 59P 59_2 59N 81O 81U
24
46 32 40 40Q
VTFF 50BF
50/27
38 49
Transient Recorder
50P 50N
50_2
51G 67G
59X
27TN
Alternatives for connection
47
81R 81A
51V 51N 55 67P 67N
50OFL
50P 50N
Metering
Event Recorder
64TN
27X
25
67_2 78
50_2
50OL
49TOL
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