Overcurrent Protection in Electrical Substations: the simple genius of the Relay

Although digital relays have replaced their older electromechanical counterparts, the terminology and theory of operation remains the same. In fact, to properly understand digital relays, a good working knowledge of the physical principles underpinning the electromechanical relay is required.

This video is a simple introduction to how overcurrent protection works in electrical substations, with emphasis on the electromechanical relay. We will look at the role of relays in overcurrent protection, the current transformer, relay settings (plug setting, time multiplier) and discrimination.

[VisualElectric_]

Should I do a video on other protection schemes? Distance or Unit protection? 🤔

[arishsiddiqui]

What an absolutely brilliant visualization. I am blown away.
Can't believe I didn't know if this channel before.

[generatorjohn]

Very basic relay protection in electrical substations. Not only feeder protection but usually motors or some cases generators, transformers.
The overcurrent relays I worked on were manufactured by General Electric model IAC or Westinghouse model CO. We would generally set the current tap, followed by the time dial. Once set, we would "bench test" and check the minimum pickup current first. Then check the operating time it would take to close the main contacts. Final test would be a functional target test which was the relay's visual target indicating which phase tripped the circuit where the fault occurred. Upon completion of tests, returned relay to service.
Very good video on the overcurrent relay concept.

[lyaeusv]

Finally I get to look at how the mechanism works ! Great video

[VictorAlvarezmx]

Excellent content, very clear and professional. Thanks for sharing this knowledge and your hard work making it.

[Adhithya]

The best video, it clears a lot of doubt, I am now currently taking protection and switchgear course, No book/video has connected the dots as much as your video. Thank you.

[HavocElect]

the animation helps a lot, much easier to understand this way.

[hajimuhammad]

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[wilsonmateus]

Thank you so much, with the industry growing in the UK this is much needed, perfect video

[mahermokhtar]

a very clear introduction to the overcurrent protection, thank you

[danielpesta]

Great explanation and fabulous animation.

[jordd]

Been binging this channels videos, all very good

[jairammangluru]

Very well explained and professionally crafted video. One of the best technical videos i have watched on youtube. Very simple and to the point. Wonderfull Sir. Thanks for your hardwork. Appreciated. Keep it up 👍👍. Am Subscribed to your channel. From India.

[libervolucion]

This video has been both interesting and very helpful. Thank you.

[DeaconBlues]

Your video is amazing man, the animations along with the explanation are so well done and you can easily understand everything! Thank you so much, I hadn't seen content like yours here in yt, very technical and very well done at the same time! New subscriber!

[mernok]

Some medium voltage circuit breakers have bult-in( integrated) relays. This eliminates the need of several meters of cable from the current transformer to the relay room and back to the circuit breaker.If that cable is damaged there is no protection.

[baylisskid]

Really simple videos. Thanks. I am very visual and this has helped a great deal.

[JohnDop]

Excellent video! Very clear and easy to understand. Thank you

[billylun]

Thankyou very much for your time and dedication in providing this helpful video❤🙏

[shavaizkhan]

Excellent Presentation ! Thanks for the video