Substation Bus Differential Protection - Best Practices When Using Modern Protective Relays

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In this video we discuss how current differential (87P) protection schemes work, using the modern microprocessor-based SEL-487B protection relay as an example.
We go over what operating and restraining currents are in protection relays, how the SEL-487B relay defines these, as well as how to calculate these currents during internal and external faults to determine protective relay operation.
This video is excerpted from Romero Engineering Company's Power System Protection: Busbar Protection online course. Check out the full course at:
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[@downunder507]

I’m a protection tech and this is gold thanks for the explanation very easy to understand and follow. Keep up the awesome work

[@romeroengineering]

Thanks! You can also find more resources that may help you here: www.romeroengineering.co/resources

[@poopface011]

So essentially the restrained differential element exists to prevent a false positive differential trip as would happen if one CT saturates. Great video!

[@romeroengineering]

Yes! We have to make sure the differential element can tolerate some CT saturation for external faults

[@synapticmemoryseepage4447]

Thank you for this video on Bus Diff Protection.

[@samuelmorales8551]

Excellent. Thanks for sharing your knowledge.

[@romeroengineering]

Thanks Samuel, glad you found this video helpful.

[@samuelmorales8551]

@@romeroengineering One question, when using this type of bus protection, should every CT wired to an input of the differential relay have a ground? Or, should all the neutral be brought together to a node and then be grounded there? Is there a preferred method for wiring the ground?

[@BG-ro3pu]

Great explanation

[@unguisan001]

Excellent explanation. Question: how is the 087p set/defined? You mentioned playing with the setting…

[@marcosspagnol7488]

Congrats on the video, thank you for sharing.
May I ask you a question: how to define the slope properly? What must be taken attention to defining the slope?
Maybe this can be a topic for a future video.
Thank you

[@joshe5180]

Very good video. Please keep it up

[@romeroengineering]

Thanks!

[@surendrakverma555]

Very good. Thanks 🙏🙏🙏🙏🙏

[@romeroengineering]

Thanks Surendra!

[@raafeterguez]

Thank you

[@romeroengineering]

You're welcome!