In the third article we learned how to configure cut-off protection (overcurretn protection second stage) and circuit breaker failure protection (CBFP).
First Vamp40 course article you can find here. Now we are going to configure non-directional earth fault protection I0>. We will also learn how to configure disturbance recorder. Suppose we are using isolated neutral 6 kV network. As we know in isolated neutral network earth leakage currents are small. So it is possible to work with earthed feeder some time in isolated neutral network. Isolated neutral network is used mainly in various industry plants. In this way we maintain uninterrupted manufacturing. It should be noted that earthed high voltage motor must immediatly stopped. In this article we are going to configure non-directional earth fault protection for feeder. Non-directional earth fault protection will not trip feeder, only will output alarm signal. Feeder will stay working. In this article we are also going to configure disturbance recorder. Disturbance recorder is used to analyse faults of the network.
The sequence of the article:
1. Non-directional earth fault first stage protection I0> configuration.
2. Connection earth fault protection I0> to binary output T2 and LED „D“.
3. Stage I0> event list configuration.
4. Stage I0> testing.
5. Stage I0> event list analysing.
6. Disturbance recorder configuration.
7. Starting disturbance recorder from stage I0>.
8. Starting disturbance recorder from stages I> and I>>.
1. Non-directional earth fault first stage protection I0> configuration. Terminal VAMP40 has 2 stages of non-directional earth fault I0>, I0>> and 2 stages of directional earth fault I0φ>, I0φ>>. We are going to use non-directional earth fault first stage protection I0>. Open configuration file of third article with „Vampset“ software. After selecting „Earth fault stage I0>“ on left side window, enter settings on right side window as shown in the picture:
Fig. 1
Press button
Fig.2
to send stage I0> settings to PLC VAMP40.
On right side window “ Earth fault stage I0>” there are options “Group 1” and “Group 2”. Because Group=1, „Group 1“ settings are active.
Here: „Pick-up setting“ – stage I0> current settings in amperes; 0.1xIn=0.1x50A=5A. Here 50 A is zero sequence current transformer‘s primary winding current rating.
“Delay curve family” – family of current curves. Selected „definite time“ (“DT”) – „Definite time“ mode means, that for example, if I0> setting is set to 5 A, and time is set to 9 s, then when current reaches 50A x 0,1 A = 5 A, after 9 s stage I0> activates (will trip).
„Delay type“ – curve type; because “Delay curve family= DT” is selected automatically „Delay type=DT“. More about curve types read in article „VAMP40 course – fider: 2. Overcurrent protection first stage“.
„Operation delay“ – stage I0> tripping time;
Configuration of stage I0> is completed. Next step is connection stage I0> to binary output T2 and LED „D“.
2. Connection earth fault protection I0> to binary output T2 and LED „D“.
Now we need to connect stage I0> tripping to binary output T2. In the figure 3 earth fault current circuit is connected to terminals X6-7, X6-8:
Fig. 3
Tripped stage I0> will active binary output T2 and LED „D“. When earth fault will remove in network, binary output T2 and LED „D“ will reset automatically. In this case we don‘t need to reset manually.
After selecting „Output Matrix“ on left side window, on right side window select dots as shown in the picture bellow (red dots):
Fig. 4
Press button
Fig. 5
to send output matrix settings to PLC VAMP40.
Simple dot „connected“ means that, when stage I0> trip, binary output T2 and LED „D“ will be activated. They will remain in activated stages until stage I0> will be activated. When earth fault will be removed in network (stage I0> resets), binary output T2 and LED „D“ will resetted automatically. In this case we don‘t need to reset manually.
3. Stage I0> event list configuration.
On left side window select „STAGE EVENT ENABLING“. Press button
Fig. 6
to read event list‘s settings from VAMP40.
On left side window „STAGE EVENT ENABLING“ select dots as shown in the picture:
Fig. 7
Send changed settings of event list to VAMP40 by pressing button:
Fig. 8
Event list configuration is completed.
4. Stage I0> testing.
Inject curents as shown in the table bellow to test stage I0>:
We can check online currents‘ measurements by using „Vampset“ software. On left side window select „Current & voltage“:
Fig. 9
Press button „Enable continous updating“ to connect to VAMP40 terminal:
Fig. 10
On left side window „Current & voltage“ check parameter „I0 residual current“:
Fig. 11
I0 residual current is 5,48 A.
After tripping earth fault protection, LED „D“ activates:
Fig. 12
When earth fault will be removed in network (stage I0> resets), binary output T2 and LED „D“ will be reseted automatically. In this case we don‘t need to reset manually.
5. Stage I0> event list analysing.
Now we need to check event list after stage I0> tripping. On left side window select „Earth fault stage I0>“:
Fig. 13
Press button
Fig. 14
to read stage I0> events.
Stage I0> events :
Fig. 15
Firts record shows that earth fault current was 0.11xpu= 0.11×50=5,5A. Option „Elapsed delay“=100% shows that 9 s elapsed and protection triped. For example, if „Elapsed delay“=70%, stage I0> would be only start.
After selecting „Event buffer“ on left side window, you can explore starting and tripping times of protection:
Fig. 16
6. Disturbance recorder configuration.
Correct configured disturbance recorder records currents, voltages measurements, starting and tripping times of protections.
On left side window select „Disturbance recorder“:
Fig. 17
Now we need to set recording channels. We are going to record IL1, IL2, IL3, Io, DO channels.
After selecting „Add recorder channel“ select „IL1“:
Fig. 18
Send changed disturbance recorder‘s settings (add channel IL1) to PLC VAMP40 by pressing button:
Fig.19
Now we can see on right side window that channel IL1 appears:
Fig. 20
Add other channels IL2, IL3, Io, DO to disturbance recorder:
Fig.21
Setting „Recording length“ set to 15 s:
Fig. 22
Parameter „Preg trig time“ set to 30%:
Fig.23
That means that disturbance recorder records 4,5 s before starting of protection and 10,5 s after protection starting: 30%x15s = 4,5 s. Parameter „Recording mode“ set to „Overflow“. Terminal VAMP40 saves 12 disturbance records. In „Overflow“ mode 13 record will be writed on oldest record. Disturbance recorder is configured.
Now we need to select which signals starts disturbance recorder. On left side window select „Output matrix“:
Fig.24
Pick dots on I> trip, I>>trip, I0> start, I0> trip on DR line (red dots):
Fig.25
Press button
Fig. 26
to send changed configuration to VAMP40.
7. Starting disturbance recorder from stage I0>.
To start disturbance recorder we need to trip stage I0>. Inject residual current I0=0,55 A.
Press button
Fig. 27
On window „Recorder log“ record „Full 2019-01-20 11:33:33.422“ appears:
Fig. 28
Disturbance recorder recorded one record.
Now we are going to open this disturbance record. Press button „View disturbance record“:
Fig. 29
Press button
Fig.30
to connect to VAMP40.
Enter passsword „0002“:
Fig.31
Press button „Apply“.
We have one record:
Fig. 32
Press button
Fig. 33
to open record.
Fig.34
Here we can see that record starts 4,5 s before starting of stage I0>:
Fig.35
Residual current was 5,5267 A.
Record‘s length after starting of stage I0> is 10,5 s.
Fig. 36
Tripping time of stage I0> is about 9s (8,935 s):
Fig. 37
After 8,935 s acivated binary output T2 and LED „D“ (figure 37). After testing stage I0> we conviced that disturbance recorder works correctly. Save record by selecting „File-Save Disturbance Record As…“:
Fig. 38
I am going to save in „.vrc“ format:
Fig. 39
Later you will able to open this file by using „Vampset“ software by selecting „File-Open Disturbance Record…“:
Fig. 40
8. Starting disturbance recorder from stages I> and I>>.
After tripping stage I>, we have another disturbance record:
Fig. 41
After tripping overcurrent I>> stage, we have third disturbance record:
Fig. 42
Stages I>, I>>, I0> trigger disturbance recorder. Configurattion of disturbance recorder is easy and intuative. We‘ve learned configure earth fault protection I0> and disturbance recorder.