basic theory of REF protection in transformers

[@SKS9091]

Very good explanation for fresh electrical protection engineers also and your calculations style also very simple easily understandable. thanks again

[@prtalks4399]

really nice sir and the way of teaching is superb and easily can understand any one. keep it sir

[@Vigneshvicky-sn1qy]

Superb sir. Your teaching superb

[@ravikumarbalasubramanian9432]

Really good ..upload more videos plz

[@electricalengineerr9711]

sure... I will be doing it soon

[@dilbadoonable]

Great explanation, thank you!

[@riteshpaul5968]

Fantastic 👍👍👍👍

[@Ravanaravanar]

please more videos uplad sar good teaching sat very nice

[@usmanharoon9078]

amazing work..upload more videos please.

[@PrabakarRamakrishnan]

good one & explain about the SEF testing how to connect the shorting cable like before or after the CT.

[@harshkumarpatel5880]

kzbin.info/www/bejne/hnbRnXmVlpd0iLM Also view this video

[@balaeswaran1919]

really good explanation... Can you share the uses of Stabilizing Resistor and Non linear Resistor in REF Protection

[@shivushankar6078]

Plz explain trip ckt sup really diagrams and healthy indication

[@PrabakarRamakrishnan]

good & also explain about SEF test where to put shorting cable.

[@manojsubramaniankrishnamoo9233]

Nice way of explanation. Please share the video link which explains about the stabilising resistor values.

[@arpansinhadmar9785]

explanation was good...

[@FULLMOON36528]

U have a unique voice...

[@flch95]

Really good videos on your channel. Good explanations, easy to understand.

[@mehrozeahmadaman6383]

Sir kindly review your video, when Ct gets saturated, current at secondary side does not reduce to zero.

[@Maverick4_SR]

It may not become zero.. but it can reduce to lower value or become disproportionate to fault current, thus current from nct and r phase ct doesn't cancel out

[@1.21gw5]

Nice Explanation , Great Clarity on the subject Do you have any videos on how to test Busbar Differential Relays If yes it would be a great help

[@pankajrastogi6834]

Please explain the 3 over current and 1nos Earth fault current scheme

[@SKS9091]

Olden days protection engineers won't tell anyone about this.but now a days not like that

[@tjjanarthananx]

Hello sir, really nice and helpful video.. i have one doubt.. if unsymmentrical fault happen mid of winding which protection relay operates first? Ref or diff.. pl clarify sir.. thanks in advance..

[@TheRajesh449]

Sir please add stabilizing resistance. Also please add what is CT saturation and why current is zero

[@rcramesh06]

Nice explanation.. looking for more videos.. I faced a problem. 4 11 kV 5400 KW motors are connected in the same bus bar. Now 3 mtrs in running condition ( no load). now I'm trying to start the 4th motor, that time any one of the motor(running) getting tripped. why??

[@vijaykumar-in4po]

Sir, Kindly tell me why differential relay is not as sensitive as REF relay ?

[@shivamvidhate3618]

Awesome!!

[@sawknitsrestha3698]

Thank u! Please upload more videos.

[@harshkumarpatel5880]

kzbin.info/www/bejne/hnbRnXmVlpd0iLM Check this also

[@murugesanramiah3653]

Dear Sir, Have you uploaded the vedio for the calculation of stabilizing resistor. If not please up load. Thank you. Please also explain about low impedance relay

[@panditvishal5451]

Nice explanation sir... But if in delta delta transformer inherent earth fault occure then how it protect?

[@neerajpiplani185]

In one of our substation whenever the 66 kv voltage is on higher side may be greater than 70 kv and if power transformer after maintenance is switched On it trips with REF indication .Could you please explain the reason for same

[@OmarBams]

Thanks for the nice explanation. but one problem I faced recently, this relay operated during unbalance current in the circuit when large motor staring since there was residual current in the line but there was no ground path in the XFMR neutral. what do think the best way to resolve this issue?

[@electricalengineerr9711]

can you please tell me whether the transformer tripped or the motor and whether it tripped through ref protection or earth fault protection.

[@OmarBams]

What tripped is the transformer relay (REF Function) However, the motor rely picked unbalance current but did not operate

[@riteshpaul5968]

Sir is 64 REF relay is only used for star connected side or in both sides of TRANSRFORMER,plz reply sir

[@paulmudditt8784]

You can use on Delta side also, but obviously only need the three line CT’s as there may be no neutral CT. If there is a zig-zag earthing transformer on the Delta side then the connection is the same as above using the 3 line CT’s and the zig-zag earthing transformer neutral CT.

[@aakash913]

Can we use only neutral ct for REF protection and not provide line cts it will still work right?

[@nelraj1360]

Dear Sir ,can u explain netural compensation of distance relay for parrel lines

[@haribalankumar4657]

nice explanation....I cleared in high impedance REF.....can you tell me the Difference between Low imp REF and High Imp Ref.....and I want to Know about basics of Low imp REF

[@wongsabarchannel1335]

Haribalan Kumar In low z relay no need the same ratio between 3 phase CT and neutral CT, because Low Z relay has capability to auto calculate, so will no trip when any fault in outside of coverage area. But when High Z relay using different CT ratio, during external fault occured it always cause the REF pick up because appear differential current in the REF coil.

[@vijaykumar-in4po]

Is there literally zero current in CT after saturation ?

[@ahmedd88]

please.,when the loads of there phases is not balanced any effect can occur?

[@electricalengineerr9711]

we add a stabilising resistance in series with the relay coil whose value is calculated considering the maximum through fault current, thus during small mismatch or unbalance relay will never operate.

[@imtiyazimtiyaz2467]

generator field aur armechuar wounding tarn thiori Natalie please

[@jasinaj5397]

during video sir says 87 relay and 64 relay. what was that. and how to know these codes

[@brightstar6587]

Sir, ur are requested to post new vdos,,

[@ZebuAlpha]

4:10 How is it possible for current to flow from phase to ground and then back to phase?

[@harshkumarpatel5880]

kzbin.info/www/bejne/hnbRnXmVlpd0iLM Check this also

[@Nightmare1756]

Hey, Can I use the same CT of Diff.Prot. to High Impedance REF Prot?

[@rajeshtk1246]

Yes. First use the CT outputs from the differential cores to the Diff relay, extract the exit points from the diff relay and form a star point and then take this star point and the differential core's original star point to the REF relay..

[@prithiviraj6960]

when CT saturated it means that secondary current will become zero? or it wont increase further as primary current increase?

[@kingworld2002]

Prithivi Raj sec current will not increase further after CT saturation.

[@vivianong560]

Saturation means second. current will not increase when prim. current increases. He meant in this video, the current flowing in the NCT will be equals to the outzone fault current. When the outzone fault current is very high to phase CT saturated, the phase CT secondary current will be lower compared to NCT secondary current, will cause the REF relay to see a vector sum not equals zero, thus tripping the circuit breaker.

[@mr.rajendrauikey1997]

rating of parameter

[@suryakantyadav128]

Can you make video in Hindi language

[@dibraniuk]

there is no need for relay 64.

[@sheharyarkhan5852]

What do you mean by jon?...i may be mishearing it..plz write spelling

[@electricalengineerr9711]

Zone

[@sheharyarkhan5852]

@@electricalengineerr9711 😊

[@jaiambrose7825]

but it is oly neutral side wdg.

[@electricalengineerr9711]

yes because only on neutral side earth fault can be detected. you can watch my video on earth fault protection in delta connected systems, for understanding it in a better way

[@electricalengineerr9711]

yes because only on neutral side earth fault can be detected. you can watch my video on earth fault protection in delta connected systems, for understanding it in a better way

[@jaiambrose7825]

thank you sir

[@20shahrukhshah4]

hindi me nhi update kr skte Hindi medium ka students kese smjhega