GE Multilin 745

A2 Metering
745
Transformer Management Relay
Actual Values
http://www.GEindustrial.com/multilin
6–9
GE Multilin
c) Total Harmonic Distortion (THD)
PATH: ACTUAL VALUES !" A2 METERING !" HARMONIC CONTENT !" THD
THD is calculated and displayed. Every THD value is calculated as the ratio of the
RMS value of the sum of the squared individual harmonic amplitudes to the RMS
value of the fundamental frequency. The calculations are based on IEEE standard
519-1986.
The actual values messages display the total harmonic distortion for phase A, B, and
C currents for Windings 1 through 3, expressed as a percentage of the fundamental
frequency component. The numbers in parentheses indicate the programmed
frequency band (in terms of harmonic number) over which THD is being calculated.
d) Harmonic Derating Factor
PATH: ACTUAL VALUES !" A2 METERING !" HARMONIC CONTENT !" HARMONIC DERATING
The Harmonic Derating Factor for each of the windings shows the effect of non-
sinusoidal load currents on power transformer’s rated full load current. The
calculations are based on ANSI/IEEE standard C57.110-1986. The actual values
messages display the harmonic derating factor for Windings 1 through 3.
! THD [!] W1 THDa (2nd-21st):
0.0% ƒo
MESSAGE
W1 THDb (2nd-21st):
0.0% ƒo
MESSAGE
W1 THDc (2nd-21st):
0.0% ƒo
MESSAGE
W2 THDa (2nd-21st):
0.0% ƒo
MESSAGE
W2 THDb (2nd-21st):
0.0% ƒo
MESSAGE
W2 THDc (2nd-21st):
0.0% ƒo
MESSAGE
W3 THDa (2nd-21st):
0.0% ƒo
MESSAGE
W3 THDb (2nd-21st):
0.0% ƒo
MESSAGE
W3 THDc (2nd-21st):
0.0% ƒo
! HARMONIC [!]
DERATING
W1 HARMONIC DERATING
FACTOR: 1.00
MESSAGE
W2 HARMONIC DERATING
FACTOR: 1.00
MESSAGE
W3 HARMONIC DERATING
FACTOR: 1.00