Rev.06
25/226
4.4.
Function 67N. Inverse time directional neutral overcurrent
Two neutral directional units are available: 67N1 and 67N2.
This function uses the residual voltage as a polarization magnitude and the residual current as
an operating magnitude. The intervention sector in forward direction is defined in the following
way: the operating angle is rotated anticlockwise from the residual negative voltage -V0, which
gives us the maximum torque direction. A cone is drawn, with the half-cone angle adjusted, over
this maximum torque direction. In the same way, the intervention sector in reverse direction is
defined in the following way: the operating angle is rotated anticlockwise from the residual
positive voltage V0, which gives us the maximum torque direction. A cone is drawn, with the half-
cone angle adjusted, over the maximum torque direction.
If the directionality option is not activated, the 67N function behaves like a 50/51N/G function.
The actuation time starts when the following conditions are met simultaneously:
•
Residual voltage higher than adjusted
•
The phase shift of residual current and residual voltage is such that the residual current is
inside the intervention sector.
•
Residual current higher than adjusted
This protection function can be set by using these parameters
Group
Description
Minimum
Maximum
Step
Unit
Default
67N_1
67N_2
Inverse time directional neutral overcurrent
Permission
-
-
Yes/No
-
No
Curve
-
-
(1*)
-
IEC Extrem.
Inverse
Time Dial (TMS)
0.02
2.20
0.01
-
1.25
Current Tap
0.10
7.00
0.01
I
nominal
0.50
Time delay
0.02
300.0
0.01
s
0.02
Directionality
-
-
(2*)
-
No
Polarization voltage
2
65
0.1
V
40
Operating angle
0
359
1
° (deg)
90
Halfcone angle
1
170
1
° (deg)
90
(1*) IEC Inverse, IEC Very Inverse , IEC Extremely Inverse , IEC long time inverse, IEEEInverse, IEEEvery inverse,
IEEEextremely inverse, Defined time
(2*) No, Forward, Reverse
If the "definite-time" option is selected for the curve setting, the unit behaves as an instantaneous
directional overcurrent unit. In this case, the unit’s Time delay is adjusted using the "Time delay"
parameter.
If an inverse, very inverse or extremely inverse curve is selected in the curve setting, the Time
delay is a function of curve, dial and pickup adjustments.
If the unit operates with definite-time, the function starts up at 100% of the adjusted pickup and
resets at 95%.
If the unit operates with a curve, the function starts up at 110% of the adjusted pickup and resets
at 100%. Resets are instantaneous in both cases.
Summary of Contents for SIL-D00
Page 8: ...www fanox com Rev 06 8 226 2 DIMENSIONS AND CONNECTION DIAGRAMS 2 1 Equipment front view...
Page 9: ...www fanox com Rev 06 9 226 2 2 Equipment dimensions...
Page 10: ...www fanox com Rev 06 10 226 2 3 Cut out pattern...
Page 12: ...www fanox com Rev 06 12 226 Digital connections Only as an example...
Page 13: ...www fanox com Rev 06 13 226 2 5 Terminals...
Page 49: ...www fanox com Rev 06 49 226...
Page 50: ...www fanox com Rev 06 50 226...
Page 51: ...www fanox com Rev 06 51 226...
Page 52: ...www fanox com Rev 06 52 226...
Page 200: ...www fanox com Rev 06 200 226...
Page 225: ...www fanox com Rev 06 225 226 NOTES...
Page 226: ...www fanox com Rev 06 226 226...
