Tripping Area
The U0/I0-
ϕ
characteristic is illustrated as a sector in the U0/I0 phasor diagram (see
). This sector
corresponds to the tripping area. If the cursor of the ground current is in this sector, the function picks up.
The tripping area is defined via several parameters: Via the angle
ϕ
(parameter 3154
50Ns-1 Phi
or 3151
50Ns-2 Phi
), the center of the zone with reference to the displacement voltage V
0
is set. Via the angle Δ
ϕ
(parameter 3155
50Ns-1 DeltaPhi
or 3152
50Ns-2 DeltaPhi
), the zone is extended to both sides of the
center.
The zone is further limited downwards by minimum values of the displacement voltage and ground current.
These settable threshold values must be exceeded in order to be picked up.
Negative angle settings turn the tripping area in the “inductiv” direction, i.e. ground current inductive
compared to ground voltage.
[enel-character, 1, en_US]
Figure 2-88
Tripping range of V0-
Ι
0-φ characteristic
Logic
The following figure illustrates the activation criteria of the sensitive ground fault protection. The operational
mode of the ground fault detection can be set under address 3101.
If set to
ON
, tripping is possible and a fault log is generated.
If set to
ON with GF log
, tripping is possible, a fault log and a ground fault log are generated.
If set to
Alarm Only
, tripping is not possible and only a ground fault log is generated.
The pickup of the displacement voltage V
0
or pickup of the 50Ns-2 element or pickup of the 50Ns-1 or 51Ns
element start the ground fault recording. As the pickup of the element drops out, fault recording is terminated
(see the following logic diagrams).
The entire function can be blocked under the following conditions:
•
A binary input is set,
•
the Fuse Failure Monitor or the voltage transformer protection breaker pick up.
Switching off or blocking means that measurement is deactivated. Therefore, time delays and pickup
messages are reset.
Functions
2.13 Ground Fault Protection 64, 67N(s), 50N(s), 51N(s)
208
SIPROTEC 4, 7SJ62/64, Manual
C53000-G1140-C207-8, Edition 08.2016
Summary of Contents for SIPROTEC 4
Page 8: ...8 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...
Page 18: ...18 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...
Page 30: ...30 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...
Page 540: ...540 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...
Page 594: ...594 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...
Page 720: ...720 SIPROTEC 4 7SJ62 64 Manual C53000 G1140 C207 8 Edition 08 2016 ...