Settings - Siemens SIPROTEC 4 User Manual

The pickup time can be prolonged at address 3303 T-det.ext.. This pickup stabilization is especially impor-
tant for the coordination with existing analog or electromechanical overcurrent relays. The time T-det.ext.
can also be disabled (T-det.ext. = 0).
The stabilized pickup starts the counter T-sum det.. This counter is stopped but not reset when the picked
up function drops out. Based on the last counter content the counter resumes counting when the stabilized
function picks up next. This sum of individual pickup times, which are to initiate tripping, is set at address
3304 T-sum det.. It represents one of the four selectivity criteria (pickup value Iie>, detection extension
time T-det.ext., counter T-sum det. and reset time T-reset) for coordinating the relays on adjacent
feeders and is comparable to the time grading of the time overcurrent protection. The relay in the radial
network which is closest to the intermittent fault and picks up, will have the shortest summation time T-sum
det..
The reset time, after which the summation is reset in healthy operation and the protection resumes normal
status, is configured to T-reset at address 3305.
[selektivitaetskrit-intermitt-erdfehler-120902-oz, 1, en_US]
Figure 2-99
Address 3306 Nos.det. specifies the number of pickups after which a ground fault is considered intermit-
tent.

Settings

2.14.3
The table indicates region-specific presettings. Column C (configuration) indicates the corresponding secon-
dary nominal current of the current transformer.
Addr. Parameter
3301 INTERM.EF
3302 Iie>
3302 Iie>
3302 Iie>
3303 T-det.ext.
3304 T-sum det.
3305 T-reset
3306 Nos.det.
SIPROTEC 4, 7SJ62/64, Manual
C53000-G1140-C207-8, Edition 08.2016
Example of selectivity criteria of the intermittent ground fault protection
C Setting Options
OFF
ON
1A 0.05 .. 35.00 A
5A 0.25 .. 175.00 A
1A 0.05 .. 35.00 A
5A 0.25 .. 175.00 A
0.005 .. 1.500 A
0.00 .. 10.00 sec
0.00 .. 100.00 sec
1 .. 600 sec
2 .. 10
2.14 Intermittent Ground Fault Protection
Default Setting Comments
OFF Intermittent earth fault
protection
1.00 A Pick-up value of interm. E/F
stage
5.00 A
1.00 A Pick-up value of interm. E/F
stage
5.00 A
1.000 A Pick-up value of interm. E/F
stage
0.10 sec Detection extension time
20.00 sec Sum of detection times
300 sec Reset time
3 No. of det. for start of int.
E/F prot
Functions
229