Understanding Permissive Over Reaching Transfer Trip POTT Communication Assisted Trip Schemes Video

We're continuing our end-to-end testing series by looking at the Permissive Over-Reaching Transfer Trip communication-assisted trip schemes. You can read the transcript at relaytraining.com/understandi...
You can play with these animations at our website relaytraining.com/pott-animat.... Each of the most commonly applied protection schemes have their own animations and they can be found at relaytraining.com/tag/end-to-e...
This video expands on the descriptions found in The Relay Testing Handbook: Principles and Practice and The Relay Testing Handbook: End-to-End Testing. You can order any of these books in print or as digital pdf downloads at our store (relaytraining.com/relay-testi....

[@abhishek894]

I have watched all the five videos. They were elegant and the animations were spot on. Thanks for sharing.

[@ravi261986]

This what i searching for last few weeks really very nice presentation and thanks for making available in free videos

[@mominhamdani4012]

excellent video. Thanks for sharing

[@shibbanik7312]

You are doing an excellent work. Keep it up.

[@Sl4gyster]

Thanks for the videos. Really well explained.

[@fredr4258]

Watched 1st 5 vids. GREAT information, good presentation and easy to understand. Thank you so much for sharing!

[@namphonethevasisomsack6125]

Thanks for your explain

[@phamphuong7931]

Thanks ad for good video!

[@intrudentalert3172]

Very clear and informative. Please make a video regarding weak infeed condition.

[@Relaytraining]

We made a post for weak infeed at relaytraining.com/please-explain-principle-weak-infeed-echo-permissive-reach-transfer-trip-schemes/?highlight=weak%20infeed

[@raobonala8818]

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.

[@Relaytraining]

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.

[@raobonala8818]

Valence Electrical Training Services Thank you

[@cristiandelaossa8296]

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

[@Relaytraining]

PUTT uses Zone 1 because it Under-reaches. POTT uses Zone 2 because it over-reaches

[@ALIK283131]

pls share one video of weak infeed scheme also..

[@owaiselectrical]

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.

[@Relaytraining]

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

[@esudeepshrestha]

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.

[@Relaytraining]

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.

[@esudeepshrestha]

Thanks for the explanation. Appreciated

[@loganathan7862]

How to choose permissive schemes (PUTT or POTT) for a line?

[@Relaytraining]

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.