Very good and clear explanation of tan delta testing. I was reading the book "Electrical Power Equipment Maintenance and Testing" by Paul Gill, but with your videos I understand the section on PF testing much better.
Hi ! I am happy to know that. To reply to your question - The reason is why we measure (not calculate) CHL, CH, CL is because you want to know what is the status of insulation between: 1. HV and GND (and that is why you measure CH) 2. LV and GND (and that is why you measure CL) 3. HV - LV (and that is why you measure CHL) The good part with Tan Delta is that you can differentiate between insulations. And then you can (for example) say - "My HV to GND insulation is bad, it needs to repaired (if it can be), but my LV insulation is good" or viceversa - "My LV to GND is bad, but HV to GND is good." or some other combination. So with Tan Delta you can be more precise when measuring insulation properties. I remember a case where HV - GND tan delta was 0,7%, and HV - LV was 0.8% but LV - GND was 2.8%, which is much more than allowed 1%. And protection was often tripping because there was a discharge LV - GND. Of course I would say CH (or Tan Delta HV - GND) is the most important - because small issue on HV can cause discharge (because voltage is higher), while on LV, also because of lower potential towards the ground, the issue is smaller is Tan Delta is a bit big. That is like a situation when you have two pipes - one with 10 bar preassure and the other with 100 bar pressure. A small hole in the 10 bar pipe presents a smaller danger than that same hole in 100 bar. I hope this helps, if not let me know.
I would like to inquire about your suggestions regarding the actions we should take for our transformer asset if the tan delta value in the LV-GND (CLG) winding is 1.10%, which exceeds the standard limit. Thanks sir.
Hi Muhammad, you should first take into consideration the voltage level of the PT. If it a EHV or HV, it is more dangerous, and also in that case if, heaven forbid, the PT malfunctions, it will be a bigger issue if it is not operational. But if it is MV and not so important, then potential damage is lower. So first asses how problematic would it be if this PT would not function. Another thing is - what to do next - so I would first see 2 things - what is the old result for that tan delta, and if it changed significantly in a short period of time, then it is a cause for alarm. But if the value was, last time you checked, not so different, if the delta is not big, then it is just a warning. But what I am trying to say is that you guys should probably do more tests. And that means - do DGA (dissolved gas analysis) and see what do the gasses in the trafo tell you about the trafo. You could find out if you have some hotspots by detecting gasses like methane, ethane, ethylene or acetylene. Or if the CO/CO2 ratio is wrong, maybe the paper could be affected, or if the O2/N2 ration is wrong, maybe a bladder or conservator is damaged and air is getting inside. If O2 values are too low, then maybe oxidation in PT is too high and acids might be affecting your transformer. For sure try and find out moisture content in your oil...BTW I am writing all this presuming you have oil filled trafo, which I suppose is true. If not then you have another approach, that also work very much with oil filled transformer, and it is Partial Discharge testing. So I would do more tests, to get a better understanding of the situation. Also feel free to contact me at asepcic@doble.com
Hi Muhammed ! You are correct. I have made mistake because tangents of 0.5 degrees is 0.00872 and not 0.0872 as I wrote. And then if I multiply 0.00872 with a 100, we get 0.872. Thank you for pointing it out and most of all for listening attentively
I am friend of Mr Praveen ( sales engineer ) from dubai . He told me that he went for desert safari with u and appreciated about ur way of explanation. I really appreciate for your explanation. I am really interested in getting knowledge from your channel . Thanks a lot
Muhammed Arief say hallo to Mr. Praveen :) and I hope you find all you need on my channel. Feel free to contact me anytime if you have some questions or comments.
Dear Mr. Sharif ! I am sorry you do not find this satisfactory. Since I am video enthusiast and an amateur I do it the best way I can. If you need a professional lecture, please write to me to andrej.sepcic@altanova-group.com and we can provide you with a fully professional training in your facility.
I'm testing HV Cables and now knows the importance of this testing.thanks a lot dude.direct and clear explanation 😊
Glad it helped
Well presented and spot on. We carried 132kV transformer testing including tan delta make sense. Much appreciated it for the effort. Thank you
Thank you very much for watching and more safe and successful testing in the future.
Very good and clear explanation of tan delta testing. I was reading the book "Electrical Power Equipment Maintenance and Testing" by Paul Gill, but with your videos I understand the section on PF testing much better.
Thank you Lex ! You are very kind and I am glad if this video helped you to get to know PF more closer.
Nice explanation, Very good video I can say related to this concept expecting similar videos in other concepts also
Glad you liked it hemanth.
Thank you for taking the time to put this out there. You've been a great help. Have you uploaded the third video in the series?
Sanele De Graaf thank you for kind words. I still did not put third video. I had to make some changes so it is taking more time then I supposed.
Good job Its very useful to me 👏👏👏
Glad to hear that Ramin
Still waiting for part 3. Thanks for your effort.
Just published sir. Please check and let me know your thoughts.
Your video helped me after 1year for my graduation project,thank you. please make a video why c is calculated in between HV LV GROUND. THANK YOU
Hi ! I am happy to know that.
To reply to your question - The reason is why we measure (not calculate) CHL, CH, CL is because you want to know what is the status of insulation between:
1. HV and GND (and that is why you measure CH)
2. LV and GND (and that is why you measure CL)
3. HV - LV (and that is why you measure CHL)
The good part with Tan Delta is that you can differentiate between insulations. And then you can (for example) say - "My HV to GND insulation is bad, it needs to repaired (if it can be), but my LV insulation is good" or viceversa - "My LV to GND is bad, but HV to GND is good." or some other combination.
So with Tan Delta you can be more precise when measuring insulation properties.
I remember a case where HV - GND tan delta was 0,7%, and HV - LV was 0.8% but LV - GND was 2.8%, which is much more than allowed 1%. And protection was often tripping because there was a discharge LV - GND.
Of course I would say CH (or Tan Delta HV - GND) is the most important - because small issue on HV can cause discharge (because voltage is higher), while on LV, also because of lower potential towards the ground, the issue is smaller is Tan Delta is a bit big.
That is like a situation when you have two pipes - one with 10 bar preassure and the other with 100 bar pressure. A small hole in the 10 bar pipe presents a smaller danger than that same hole in 100 bar.
I hope this helps, if not let me know.
@@sheppo17 yes it helps me (◍•ᴗ•◍) thank you very much for your response.
Thank you so much ....Sir. Waiting for your third video.
Just published sir. Please check and let me know your thoughts.
Very good explanation, waiting the next part
Just published sir. Please check and let me know your thoughts.
Sir eagerly waiting for your 3rd video in the series
Just published sir. Please check and let me know your thoughts.
Nice! Cant wait for the next video :-D two thumbs up!
Thank you very much Arief for your comment. It is very much appreciated !
I would like to inquire about your suggestions regarding the actions we should take for our transformer asset if the tan delta value in the LV-GND (CLG) winding is 1.10%, which exceeds the standard limit. Thanks sir.
Hi Muhammad, you should first take into consideration the voltage level of the PT. If it a EHV or HV, it is more dangerous, and also in that case if, heaven forbid, the PT malfunctions, it will be a bigger issue if it is not operational. But if it is MV and not so important, then potential damage is lower. So first asses how problematic would it be if this PT would not function. Another thing is - what to do next - so I would first see 2 things - what is the old result for that tan delta, and if it changed significantly in a short period of time, then it is a cause for alarm. But if the value was, last time you checked, not so different, if the delta is not big, then it is just a warning. But what I am trying to say is that you guys should probably do more tests. And that means - do DGA (dissolved gas analysis) and see what do the gasses in the trafo tell you about the trafo. You could find out if you have some hotspots by detecting gasses like methane, ethane, ethylene or acetylene. Or if the CO/CO2 ratio is wrong, maybe the paper could be affected, or if the O2/N2 ration is wrong, maybe a bladder or conservator is damaged and air is getting inside. If O2 values are too low, then maybe oxidation in PT is too high and acids might be affecting your transformer. For sure try and find out moisture content in your oil...BTW I am writing all this presuming you have oil filled trafo, which I suppose is true. If not then you have another approach, that also work very much with oil filled transformer, and it is Partial Discharge testing. So I would do more tests, to get a better understanding of the situation. Also feel free to contact me at asepcic@doble.com
Thank you so much
My pleasure dear engineer Omar !
a very good video! Thanks a lot :-D
Thank you very much Ereda !
Please upload third video...half knowledge is as good as poison
Just published sir. Please check and let me know your thoughts.
i need this data as like pdf
Hi ! Send me please your email to andrej.sepcic@altanova-group.com
Sir can you give ne pdf file of this test
Deepak Rawat sure, send me your email or write to me to andrej.sepcic@altanova-group.com
@@sheppo17 deepakrawat1994.dr@gmail.com
where is part 3
Hi Saif ! Thanks for your comment. The third part is being made and I hope you will see it in the next few weeks.
Thanks for your reply and appreciate your effort and hoping more success for you
@@saifeldientarek31, Thank you very much ! A lot of success to you too !
Tangents 0.5 degree should be 0.00872686
Correct
At 13:13 video 0.0872686x100 = 8.726%
Hi Muhammed ! You are correct. I have made mistake because tangents of 0.5 degrees is 0.00872 and not 0.0872 as I wrote. And then if I multiply 0.00872 with a 100, we get 0.872. Thank you for pointing it out and most of all for listening attentively
I am friend of Mr Praveen ( sales engineer ) from dubai . He told me that he went for desert safari with u and appreciated about ur way of explanation. I really appreciate for your explanation. I am really interested in getting knowledge from your channel . Thanks a lot
Muhammed Arief say hallo to Mr. Praveen :) and I hope you find all you need on my channel. Feel free to contact me anytime if you have some questions or comments.
Andrej Sepcic yes definitely.
Can not concentrate my mind on inforatibe lecture ; video was very hazy the camera Projektion was not that expertism.
Dear Mr. Sharif ! I am sorry you do not find this satisfactory. Since I am video enthusiast and an amateur I do it the best way I can. If you need a professional lecture, please write to me to andrej.sepcic@altanova-group.com and we can provide you with a fully professional training in your facility.
false information about tan tan delta value expression
Could you please specify which ones ?
What is tan 0.25° ? And what you write down?