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

In this video we discuss how to protect a transmission line implementing a distance protection scheme using the SEL-421 protection relay as an example. We go over how to calculate the Zone 1 (underreaching) and Zone 2 (overreaching) settings to develop a robust protection scheme that protects the entire transmission line.

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00:00 Intro
00:30 Mho element plotter spreadsheet
02:35 Zone 1
04:03 Zone 2
05:10 Example transmission line settings
12:30 Programming the SEL-421 Relay

[patrickcannell]

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

[fioricoziuc]

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

[anandarajkarthikeyan]

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

[jeffwebb]

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

[TrentMRobertson]

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

[romelbacay]

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

[sonaimuthu]

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

[romelbacay]

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