Siemens SIPROTEC 4 User Manual page 232

Functions
2.15 Dir. Intermittent earth fault protection
[7sj62-64-iefger-aktiv-20120611, 1, en_US]
Figure 2-100
Measurand Acquisition
The intermittent ground fault current 3I0 is measured exclusively via the sensitive ground current input INs
(4th current transformer input) of the device.
Also the displacement voltage V
can be applied directly to the device, or the summation voltage 3 · V
to-ground voltages.
If the displacement voltage is calculated, then:
3 · V = V + V + V
0 A B
If the displacement voltage is directly applied to the device, then V
not affected by parameter Vph / Vdelta (address 206).
Fault Log, Ground Fault Log, Fault Recording
Parameter Dir. Interm. EF allows you to define the type of fault handling and fault logging. If set to ON,
tripping is possible and a fault log is generated. If set to ON with ON with GF log, tripping is possible, a
fault log and a ground fault log are generated. If set to Alarm Only, no tripping is possible. Only an alarm is
generated. Furthermore, only a ground fault log is created.
The raising pickup of the function (indication 6972
fault log.
Logic Diagram
The following figure shows the logic diagram of the directional intermittent ground fault protection function.
232
Activation of the directional intermittent ground fault protection
or 3 · V is required to determine the direction. The displacement voltage V
0 0
C
can be calculated from the three phase-
0
is the voltage at the device terminals. It is
0
dIEF pick up ) is the criterion for opening the ground
C53000-G1140-C207-8, Edition 08.2016
0
SIPROTEC 4, 7SJ62/64, Manual