Distance Protection of Transmission Lines | Example Using the SEL-421 Protection Relay

[@romeroengineering]

Learn more with our online courses here: www.romeroengineering.co/courses

[@patrickcannell2258]

As a seasoned protection engineer myself, very well put in such short time.

[@fioricoziuc1792]

You teach very well and in a clear way! Thank you! I wish you were my professor !

[@romeroengineering]

Thanks! You can see our courses here if you're looking for more in-depth training: www.romeroengineering.co/courses

[@anandarajkarthikeyan3917]

I doubt that anyone can explain such complicated topic much easier than this. Thanks !

[@romeroengineering]

Glad it was helpful Anandaraj!

[@jeffwebb8208]

This was explained very well. The spreadsheet is very useful. Thank you!

[@romeroengineering]

Glad it was helpful!

[@TrentMRobertson]

You're awesome! Thanks for the spreadsheet and detailed, yet concise explanation!

[@romeroengineering]

Thanks Trent, glad you're finding the videos helpful.

[@patakotisrinivas1918]

Thanks for an awesome explanation

[@pinankpatel7853]

This was great explanation!

[@romeroengineering]

Thanks!

[@surendrakverma555]

Excellent explanation Sir. Thanks 👍

[@romelbacay8325]

Thank you sir for this very informative and simple explanation..👍👍👍

[@romeroengineering]

Thanks!

[@Alvin-og1li]

Thanks mate, keep it coming

[@romeroengineering]

Thanks, will do!

[@Magno.LSoares]

Great content Romero! Thank you!

[@romeroengineering]

Thanks Magno!

[@myenergyprojects]

youtube.com/@myenergyprojects?si=BVtbeFARuwtDCxn2 please refere for all basics and knowledge information . Hi sorry for posting my channel link

[@sergiopena1602]

Great presentation. Thank you

[@romeroengineering]

Thanks Sergio!

[@awareofdeath]

Thank you so much

[@sonaimuthu2060]

SUPER EXPLANATION WE NEED ENGLISH SUB TITLE ..BECOZ I AM NOT GOOD FAST ENLGISH SPEECH SO PLEASE MAKE IT SUBTITLE FOR LEARNING

[@martingreco7473]

Fantastic, Thanks

[@romeroengineering]

Thanks Martin!

[@myenergyprojects]

youtube.com/@myenergyprojects?si=BVtbeFARuwtDCxn2 please refere for all basics and knowledge information . Hi sorry for posting my channel link

[@romelbacay8325]

Sir, what are your assumptions about the 30 cycles of Zone 2? I've seen some Zone 2 settings as 75 cycles. Thank you.

[@romeroengineering]

Hi Romel, this depends on your coordination, there isn't a right or wrong answer here, it just depends on what you are coordinating with. A 30-cycle delay on a Zone 2 element is typical though, based on the fact that this would usually just need to coordinate with instantaneous protection at the remote end. So, 30 cycles (0.5 seconds) allows for enough time for instantaneous elements to operate, trip the breaker, and perform a breaker failure function if needed. Then, if none of this happens, the remote ends back up with a Zone 2 delay at 30 cycles. Again, it all depends on what you are coordinating with.

[@patrickcannell2258]

Very well put. I work in a 50 hz area and normally go 20 cycles or 400 ms. But again co ordination with next Z2 is essential if on Z2 encroaches the next. This happens if you have a long line folled by a very short line. ​@romeroengineering

[@patrickcannell2258]

75 cycles is just over a second with 60 hz and a second and a half with 50 hz! Long for an end zone fault! Can your system tolerate such a dip? And hard on the feeding transformer. In most cases the transformer feeding back up earth fault or overcurrent will trip shutting down everything. Also co ordination with up stream and down stream protection has to be considered.

[@VictorMaldonado-t8n]

Thanks!

[@romeroengineering]

No problem!