We made a post for weak infeed at relaytraining.com/please-explain-principle-weak-infeed-echo-permissive-reach-transfer-trip-schemes/?highlight=weak%20infeed
Thanks for the great animation to explain the chronology of fault duration and BKR operations. However, in this video of POTT, the parallel line relays (relay 5 and 6) operations is not understood. - Before BKR1 is tripped Relay 5 is detected Zone 3 fault and after the BKR 1 is tripped the fault current direction is changed and Zone 2 fault is detected. - But, how Relay 6 which is detecting Zone 2 fault before BKR 1 trip, is still detecting Zone 2 fault even after Current reversal, not Zone 3? Hope you can clarify. Thanks again.
Thanks for the question. As stated in the video, nothing happens instantaneously. The two relays may detect the sudden current reversal simultaneously, but the local relay can detect a Zone 2 before the communication signal from the other relay changes.
As you said that when reversal of current occurs, relay5 will detect Zone2. But actually fault seems to be in a zone which is more than120% for Relay5. Can you explain.
Follow the current flow through relay 5 before and after the reversal remembering that the two parallel line ends are basically on top of each other impedance-wise
For relay 5 & 6 are we still talking about the same fault shown between relays 1 & 2? Or relays 5 & 6 see a fault within between them to activate zone 1 or zone 2. Thank u. Really enjoyed the video and have watched at least 5 times now.
Yes it is the same fault. Relay 5 initially sees a fault behind it because of the current flow. Relay 6 could possibly see it as a Zone 2. Everything changes when Bkr 1 opens because the currents all suddenly change direction and it becomes a race of who see what when.
Thanks for yours explanations are really clear and so good @Valence Electrical Training Services, could you help me with a doubt I can not see a difference between PUTT and POTT scheme, could you or somebody show me the difference between these schemes Thanks for advantage
You have to do a system study to see if your system has enough energy to over-reach or under-reach, then decide whether you want security or reliability.
I have watched all the five videos. They were elegant and the animations were spot on. Thanks for sharing.
This what i searching for last few weeks really very nice presentation and thanks for making available in free videos
You are doing an excellent work. Keep it up.
Watched 1st 5 vids. GREAT information, good presentation and easy to understand. Thank you so much for sharing!
excellent video. Thanks for sharing
Very clear and informative.
Please make a video regarding weak infeed condition.
We made a post for weak infeed at relaytraining.com/please-explain-principle-weak-infeed-echo-permissive-reach-transfer-trip-schemes/?highlight=weak%20infeed
Thanks for the videos. Really well explained.
Thanks ad for good video!
Thanks for the great animation to explain the chronology of fault duration and BKR operations. However, in this video of POTT, the parallel line relays (relay 5 and 6) operations is not understood.
- Before BKR1 is tripped Relay 5 is detected Zone 3 fault and after the BKR 1 is tripped the fault current direction is changed
and Zone 2 fault is detected.
- But, how Relay 6 which is detecting Zone 2 fault before BKR 1 trip, is still detecting Zone 2 fault even after Current reversal, not Zone 3?
Hope you can clarify. Thanks again.
Thanks for the question. As stated in the video, nothing happens instantaneously. The two relays may detect the sudden current reversal simultaneously, but the local relay can detect a Zone 2 before the communication signal from the other relay changes.
Valence Electrical Training Services Thank you
As you said that when reversal of current occurs, relay5 will detect Zone2. But actually fault seems to be in a zone which is more than120% for Relay5. Can you explain.
Follow the current flow through relay 5 before and after the reversal remembering that the two parallel line ends are basically on top of each other impedance-wise
For relay 5 & 6 are we still talking about the same fault shown between relays 1 & 2? Or relays 5 & 6 see a fault within between them to activate zone 1 or zone 2. Thank u. Really enjoyed the video and have watched at least 5 times now.
Yes it is the same fault. Relay 5 initially sees a fault behind it because of the current flow. Relay 6 could possibly see it as a Zone 2. Everything changes when Bkr 1 opens because the currents all suddenly change direction and it becomes a race of who see what when.
Thanks for the explanation. Appreciated
Thanks for yours explanations are really clear and so good @Valence Electrical Training Services, could you help me with a doubt I can not see a difference between PUTT and POTT scheme, could you or somebody show me the difference between these schemes
Thanks for advantage
PUTT uses Zone 1 because it Under-reaches. POTT uses Zone 2 because it over-reaches
pls share one video of weak infeed scheme also..
Thanks for your explain
How to choose permissive schemes (PUTT or POTT) for a line?
You have to do a system study to see if your system has enough energy to over-reach or under-reach, then decide whether you want security or reliability.