Figure. 5.4.8. - 50. Simpli ed function block diagram of the HOC function.
Measured input values
Function block uses analog current measurement values from the phase currents or residual currents.
For each measurement input the HOC function block utilizes the fundamental frequency and harmonic
components of the selected current input and by user selection the monitored magnitude can be either
per unit RMS values of the harmonic component or harmonic component percentage content
compared to fundamental frequency RMS. -20ms averaged value of the selected magnitude is used for
pre-fault data registering.
Table. 5.4.8. - 94. Analogic magnitudes used by the HOC function.
Signal
Description
Time
base
IL1FFT
Magnitudes (rms) of phase L1/A current components: Fundamental, 2
nd
harmonic, 3
rd
harmonic, 4
th
harmonic, 5
th
harmonic 7
th
, harmonic 9
th
, harmonic 11
th
, harmonic 13
th
, harmonic 15
th
, harmonic 17
th
,
harmonic 19
th
harmonic current.
5 ms
IL2FFT
Magnitudes (rms) of phase L2/B current components: Fundamental, 2
nd
harmonic, 3
rd
harmonic, 4
th
harmonic, 5
th
harmonic 7
th
, harmonic 9
th
, harmonic 11
th
, harmonic 13
th
, harmonic 15
th
, harmonic 17
th
,
harmonic 19
th
harmonic current.
5 ms
IL3FFT
Magnitudes (rms) of phase L3/C current components: Fundamental, 2
nd
harmonic, 3
rd
harmonic, 4
th
harmonic, 5
th
harmonic 7
th
, harmonic 9
th
, harmonic 11
th
, harmonic 13
th
, harmonic 15
th
, harmonic 17
th
,
harmonic 19
th
harmonic current.
5 ms
I01FFT
Magnitudes (rms) of residual I01 current components: Fundamental, 2
nd
harmonic, 3
rd
harmonic, 4
th
harmonic, 5
th
harmonic 7
th
, harmonic 9
th
, harmonic 11
th
, harmonic 13
th
, harmonic 15
th
, harmonic 17
th
,
harmonic 19
th
harmonic current.
5 ms
I02FFT
Magnitudes (rms) of residual I02 current components: Fundamental, 2
nd
harmonic, 3
rd
harmonic, 4
th
harmonic, 5
th
harmonic 7
th
, harmonic 9
th
, harmonic 11
th
, harmonic 13
th
, harmonic 15
th
, harmonic 17
th
,
harmonic 19
th
harmonic current.
5 ms
Selection of the used AI channel and monitored harmonic as well as per unit monitoring or percentage
of fundamental monitoring is made with a setting parameter. In all possible input channel variations
pre-fault condition is presented with 20 ms averaged history value from -20 ms of Start or Trip event.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
98