GE 869 Instruction Manual page 564

MOTOR
6–8
LOAD BIN
Load bin (1 to 12) represents at which loading condition the motor (or bearing, or
mechanical fault, or stator fault) is computed from the 1 to >110% range with each bin
comprising 10% load interval and 100% representing rated load.
TIME OF BASELINE COMPUTATION
Time of baseline computation is the time extracted when the Avg. highest normalized peak
magnitude (base line) and Avg. energy at peak magnitude (base line) values are computed
at the end of the base line period.
NORMALIZED PEAK MAGNITUDE at k=1 (2 or 3)
Normalized Peak Magnitude in dB represents the peak magnitude observed in FFT
computation at all corresponding fault frequencies representing fault at k = 1,2,3 for a
specific load bin.
ENERGY AT PEAK MAG at k=1 (2 or 3)
Energy at Peak Magnitude in dB represents the area observed within +/- 0.5 Hz region in
FFT computation at the fault frequency corresponding to NORMALIZED PEAK MAGNITUDE
at k=1 (2 or 3) for a specific load bin.
MAX CHANGE IN MAG dB at k=1 (2 or 3)
Max Change in Mag in dB represents the highest after the difference between normalized
dB magnitude calculated with respect to baseline normalized peak magnitude dB (for all k-
factors) for a specific load bin.
MAX CHANGE IN ENERGY at k=1 (2 or 3)
Max Change in Energy in dB, represents the highest difference between energy magnitude
calculated with respect to baseline energy dB (for all k-factors) for a specific load bin.
ESTIMATED SPEED
The 869 relay estimates speed based on rated input power, rated speed and power input
to the motor. This field displays estimated speed.
TIME OF FAULT COMPUTATION
This time represents the 8 Series local time at which the Highest normalized peak and
energy magnitudes are computed within each ESA cycle.
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: METERING