Thytronic DMC3S - Ground Directional Overcurrent - 67 N (Evolving Faults)

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DMC3S - Manual - 08 - 2021
— Ground directional overcurrent - 67N (Evolving faults)
Preface
The maximum directional ground current protection function 67N for detecting evolving arcs detects
the type of intermittent fault originating in sequence on different feeders.
Detection is done logically controlling the start statuses generated by protection function 67N, by
starting a specific 59N threshold, or by receiving the Goose IEC61850 for the state of start by residual
overvoltage of the protection.
The logic of threshold IED>>>>> is shown in the following figure:
char-F67N-evolutivi.ai
tED>>>>>RRIC
IED>>>>-UE>
T
R
0
tED>>>>>O
T0
tED>>>>>RRIC
tED>>>>>RAO
tED>>>>>O
T 0
tED>>>>>RAO
Start UE>Ext
≥1
≥1
&
(ON Enable)
IED>>>>-IED>Av Enable
Start IED>
&
(ON Enable)
IED>>>>-IED>>a_Av Enable
Start IED>>a
Start IED>>b
&
(ON Enable)
IED>>>>-IED>>b_Av Enable
&
(ONEnable)
In dig.(61850)
IED>>>>-UeExt_Av Enable
&
TripIED>>>>>
UE
&
State
UE ≥IED>>>>-UE>
Functional diagram of the threshold of the directional ground protection against evolving faults (67N)