Thytronic NA30, Руководство пользователя

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FUNCTION CHARACTERISTICS
85 NA30 - Manual - 04 - 2022
For both the operating modes, the measured U
E
voltage is employed as polarizing reference for
displacement measure of the residual current.
The displacement of the residual current phasor I
E
and the residual voltage phasor ( U
E
), positive for
lagging current compared with voltage ( Φ
E
=( ∠ I
E
- ∠ U
E
).
For each of the four thresholds ( I
ED
>, I
ED
>>, I
ED
>>>, I
ED
>>>>) , the characteristic angle ( ϑ
E
>, ϑ
E
>>,
ϑ
E
>>>, ϑ
E
>>>>) may be adjusted (setting range 0…359° common for the three phases).
The the characteristic angle setting (positive when clockwise compared the polarizing voltage)
specifies the angular displacement of the characteristic axis standing for the trip bisector of the
tripping zone.
For isolated neutral systems with a 90° characteristic angle setting, faults towards the LINE are
detected, while with a 270° characteristic angle setting, faults towards the BUS are detected.
All the named parameters can be set separately for the four thresholds and for definite or inverse
time settings menu
For each of the four thresholds ( I
ED
>, I
ED
>>, I
ED
>>>, I
ED
>>>>), the half operating sector may be ad-
justed (setting range 0…180° simmetrically regarding the characteristic axis).
All the named parameters can be set separately for the four thresholds and for definite or inverse
time settings menu.
For all the four thresholds ( I
ED>
, I
ED>>
, I
ED>>>
, I
ED>>>>
), the operating mode when the 74VT function is
active may be defined:
• OFF: no action are issued by 74VT.
• Block: all the four thresholds are blocked when the 74VT function is active.
• Not directional: all the four thresholds are switched from directional to not directional criteria
when the 74VT function is active.
The 74VT information may be issued from an external signal acquired by means a binary input.
If a binary input is designed for 74VText, for all the four thresholds, the operating mode when the 74VT
function is active may be defined:
char-F67N-mode.ai
Operating characteristics of the earth fault overcurrent element - 67N
with module operating mode (I)
Operating characteristics of the earth fault overcurrent element - 67N
with projection operating mode ( I∙cos)
I
E
U
E
U
EC
Characteristic axis
Characteristic axis
Φ
E
o Φ
EC
Half operating sector
(
β
E>
,
β
E>>
,
β
E>>>
,
β
E>>>>
)
Half operating sector
( β
E>
, β
E>>
, β
E>>>
, β
E>>>>
)
Half operating sector
( β
E>
, β
E>>
, β
E>>>
, β
E>>>>
)
Half operating sector
(
β
E>
,
β
E>>
,
β
E>>>
,
β
E>>>>
)
Threshold ( I
ED threshold
):
( I
ED
>, I
ED
>>, I
ED
>>>, I
ED
>>>>)
(M∙ I
ED
>, M∙ I
ED
>>, M∙ I
ED
>>>, M∙ I
ED
>>>>)
Threshold ( I
ED threshold
):
( I
ED
>, I
ED
>>, I
ED
>>>, I
ED
>>>>)
(M∙ I
ED
>, M∙ I
ED
>>, M∙ I
ED
>>>, M∙ I
ED
>>>>)
I
E
Φ
E
o Φ
EC
Characteristic angle
Characteristic angle
( Θ
E>
, Θ
E>>
, Θ
E>>>
, Θ
E>>>>
)
( Θ
E>
, Θ
E>>
, Θ
E>>>
, Θ
E>>>>
)
U
E
U
EC
I
E
≥ I
ED threshold
I
ED threshold
I
E
I
I∙cos
Mode67N
I
E
∙
COS
( ϑ
E -
Φ
E
) ≥ I
ED threshold
I
ED threshold
I
E
I
I∙cos
Mode67N
Φ
E
o Φ
EC
U
E
U
EC
3Votype67N
NA60
BUSBAR
I
E
U
E
RESIDUAL
VOLTAGE INPUT
B7 terminal
C7 terminal
RESIDUAL
CURRENT INPUT
Trip sector
(toward line)
Trip sector
(toward line)
No trip sector
(toward busbar)
No trip sector
(toward busbar)
Operating characteristics of the ground directional overcurrent elements - 67N
LINE