Electrical Notes

Notes on Electrical Engineering:

All Notes & Abstracts are Based on Some Electrical References. All References are mention at end of each Notes.

BUY All Electrical Notes in PDF Format (US$)

BUY All Electrical Notes in PDF Format (Indian Rs)

  1. Calculate No of Lighting Fixtures / Lumen for Indoor Lighting
  2. Calculate Size of Capacitor Bank / Annual Saving & Payback Period
  3. Calculate Cable Size and Voltage Drop
  4. Calculate Technical Losses of Transmission / Distribution Line
  5. Selection of 3P-TPN-4P MCB & Distribution Board
  6. Calculate IDMT over Current Relay Setting (50/51)
  7. Electrical Thumbs Rules (Part-10)
  8. Electrical Thumbs Rules (Part-9)
  9. Electrical Thumb Rules-(Part-8)
  10. Electrical Thumb Rules-(Part-7)
  11. Electrical Thumb Rules-(Part-6)
  12. Electrical Thumb Rules-(Part-5)
  13. Electrical Thumb Rules-(Part-4)
  14. Electrical Thumb Rules-(Part-3)
  15. Electrical Thumb Rules (Part-2)
  16. Electrical Thumb Rules-(Part 1).
  17. Total Losses in Power Distribution and Transmission Lines-Part 2
  18. Total Losses in Power Distribution & Transmission Lines-Part 1
  19. Calculate TC Size & Voltage Drop due to starting of Large Motor
  20. Calculate Size of Contactor, Fuse, C.B, Over Load Relay of DOL Starter
  21. Calculate Number of Lighting Fixtures & Lux Level
  22. Calculate Voltage Regulation of Distribution Line
  23. Calculate Size of Transformer and Voltage drop due to starting of large size motor
  24. Design DOL / Star-Delta Starter
  25. Calculate Size of Motor-Pump
  26. Calculate Numbers of Plate/Pipe/Strip Earthings (Part-3)
  27. Calculate Numbers of Plate/Pipe/Strip Earthings (Part-2)
  28. Calculate Numbers of Plate/Pipe/Strip Earthings (Part-1)
  29. Size and Location of Capacitor in Electrical System-(Part 2)
  30. Size and Location of Capacitor in Electrical System-(Part1)
  31. Calculate Number of Plate / Pipe Earthing
  32. Size of Capacitor Bank for Power Factor Correction
  33. Difference between Unearthed Cable & Earthed Cables
  34. Over Current Relay(Type-Application-Connection)
  35. Calculate Transformer Over current Protection (As per NEC 450.3)
  36. Types and Revolution of Electrical Relays
  37. Transformer IDMT Over Current & Earth Fault Relay Setting
  38. IDMT Over Current Relay Grading Calculation (50/51)
  39. IDMT Relay Setting & Curves
  40. Calculation of IDMT Over current & Earth Fault Relay Setting
  41. Abstract of over current Protection of Transformer (NEC 450.3)
  42. Difference between Bonding, Grounding and Earthing
  43. Safety Clearance for Transformer
  44. Safety Clearance for Electrical Panel
  45. Electrical Safety Clearance (Part-6)
  46. Electrical Safety Clearance (Part-5)
  47. Electrical Safety Clearance (Part-4)
  48. Electrical Safety Clearance (Part-3)
  49. Electrical Safety Clearance (Part-2)
  50. Electrical Safety Clearance (Part-1)
  51. Impact of Floating Neutral in Power Distribution
  52. Parallel Operation of Transformer
  53. Vector Group of Transformer
  54. Auto Transformer Connection
  55. Scott-T Connection of Transformer
  56. Zig-zag Connection of Transformer
  57. Star-Delta Connection of Transformer
  58. Delta-Star Connection of Transformer
  59. Delta-Delta Connection of Transformer
  60. Star-Star Connection of Transformer
  61. Calculate % Voltage Regulation of Small Distribution Line.
  62. Insulation Resistance (IR) Values
  63. Star-Delta Starter
  64. Direct On Line Starter
  65. Effects of High Voltage Transmission Lines on Humans and Plants
  66. Analysis the Truth behind Household Power Savers
  67. Types of Neutral Earthing in Power Distribution
  68. EHV/HV Cable Sheath Earthing
  69. Abstract of NEC for Size of Cable for Single or Group of Motors
  70. HIPOT Testing
  71. What is Earthing
  72. Abstract of National Electrical Code for Transformer’s Protection
  73. Guideline to Design Electrical Network for Building / Small Area.
  74. Demand Factor-Diversity Factor-Utilization Factor-Load Factor
  75. Calculate Transverse Load on PCC/RCC/Tublar/RSJ Pole.
  76. Working Principle of ELCB and RCB
  77. Single Earthed Neutral and Multi Earthed Neutral.
  78. Type of Electrical Power Distribution systems
  79. Type of Cable Tray.
  80. Electrical Programs (Excel Base)
  81. Sub Station Abstracts
  82. Tampering Methods of Electrical Energy Meter.
  83. 11KV/415V Overhead Line Specification as per REC
  84. Specification for Rewirable Cut Out Fuse Unit
  85. Low Voltage and High Voltage Cable Testing
  86.  Home / Office Programs (Excel Base
  87. Overload Relay & Contactor for Starter
  88. Type of Gland
  89. Gland Size Selection
  90. EHV XLPE – Current Rating
  91. XLPE Cable-Current Rating
  92. PVC Cable-Current Rating
  93. Fuse
  94. Difference between Power Transformer and Distribution Transformer
  95. Current Transformer
  96. Electrical Clearance in Substation.
  97. Minimum Electrical Clearance.
  98. Minimum Acceptable specification for Metering C.T
  99. Typical Limiting Values of Substation Equipments.
  100. Lighting Arr ester
  101. Standard Makes for Electrical Equipments
  102. Electrical Motor Connections
  103. Power Quality
  104. Ferranti Effect in Transmission Line
  105. What is Corona Effect in Transmission Line 
  106. Electrical Excel Tools 
  107. How Reactive Power helpful to maintain a System Healthy
  108. Automatic Power Factor Correction
  109. Harmonics and It’s Effects
  110. HID Lamps
  111. Types of Overhead Conductors
  112. Difference Between  MCB/MCCB/ELCB/RCCB
  113. Vibration Damper in Transmission Line
  114. Electrical Energy Saving Tips
  115. Transformer

131 Responses to Electrical Notes

  1. noel ramos says:

    subscribe me about your Electrical Notes posts

  2. Habeeb says:

    Thanks for you and your website. It is very useful for all electrical engineers.

  3. VIKRAM says:


  4. gobinath says:

    what is the reason for in earth fault relay does not operate while fault occurs near by the neutral point

  5. mozes says:


  6. ritu says:

    hey…ur website is really very very good…plzz keep up the great workk…god bless you…u are amzinngngngng!!!

  7. Varun says:

    God Bless U, Sir u are doing a great work.Thanking U.

  8. Nandip Agrawal says:

    Please let me know abour Surge Protector in details

    How Surge protector is installed in Main Distribution Panel ?

  9. BBQ Grill Covers says:

    This article was really nicely written, and it also contains several helpful details. I appreciated your expert manner of writing this submit. You’ve created it easy for me to realize.

  10. Dear sir,
    your web site very useful for all Electrical Engineer.
    I want to know for Earthing Truck 11kv ,sub station automation.

  11. dipalee says:

    this website is really great…..!! thank you sir…

  12. Anand says:

    Dear sir

    Will u explain the duty cycle of the breakers i.e O-0.3Sec-CO-3Mins-CO

  13. sheeba says:

    if possible ,include somthing about electrical system design & estimation……….

    It is very helpful for us.

  14. Mboga Ratego says:

    I have a 500kVA generator supplying 33kV line with a distance of 55km, The line has 7 transformers at the receiving i.e 55 km from the generator station, the problem is that this system has refused to work, it trips after every 3 hours, What could be the problem with this arrangement,The voltage is too high at the receiving going upto 255V for single phase, attempts to transpose the line has also failed to work

  15. can u give me UPS sizig and BBank sizing calculation

  16. subhash says:

    this site is wonderful i will inform my friends also about this site u r doing gate job

  17. Masood says:

    please tell me how i can see current transformer pdf view because when i open pdf file of current transformer it show wordpress registration i completed registration but no view of pdf. please reply thx

  18. narendra charola says:

    it’s real good collection keep it up.

  19. aditya says:

    Can u explain about grouser an Earth fault detector

  20. bharat says:

    What would be minimum clearence betn HV bushing top lead abd upper gandry?

  21. mansoor says:

    Hello Sir

    Thank u very much for uploading these information, can u upload UPS Selection and cable selection for UPS and Cable/ Copper strip size for UPS Neutral earthing? and some important information about electrical design for distribution side of IT, Residential & Commercial buildings.

  22. jagadish says:

    hello sir,

    firstly i want to thank you… secondly can i known about power quality in elobrated way plssss

  23. sateesh says:

    useful site for all electrical engineers.

  24. sir please i really need the current transformer notes but i can,t acess on that notes so can you help me about that.
    waiting your reply

  25. sathish kumar says:

    hello sir,
    relly great work.sharing of knowledge makes it you different from others

  26. Mitul says:

    Hi Jignesh..Good work…keep it up..
    I want to know about Partical Discharge Test.

  27. ranjeet p.desai says:

    thanks for sharing

  28. bani says:

    hi jignesh its really good work….i want to know switch gear,,,more….but no notes regarding that
    pls can u update….this site s very helpful for us…..good

  29. Mohd Daud Othman says:

    good reference for me…tq

  30. Ugo Ezeani says:

    I can only say you are doing a great job. You are a gift to the electrical community
    Please can i get your e mail address.

  31. Dashmesh Singh says:

    best site for practical engineers


    Dear jignesh
    i must applaud you for such beautiful,simplified and greatly livid articles. you are infact generating tremendous interest level among the common engineers , your article seems to be a engrossing novel for the all the level of technocrats . My hats off to you for a yeoman service .

    Arvind Singh Rathore

  33. joseph says:

    can u blog something about 1 phase and 3 phase motors

  34. Min Htet says:

    can you send your all post as PDF files to my email because your all posts are very great and useful to me? I afraid, I can not visit your website one day.

    • Dear Min,
      Just Copy of the text from Blog-open MS word just past it then convert it to PDF if you need in PDF.
      It is not possible to convey PDF copy of all Notes personally to every one.

  35. prasad says:

    Dear Parmar sir,

    You hav given such a wonderfull information, as there are so many sites but this is one and only site which fullfill any electrical engineer or contracter information needs. And ur excel programs are also wonderfull. Now i m became fan of u. I future days i will defenatiely donate as well i will buy excel program also.

    Thank you very much. God bless u.

  36. DIPA, Ahmedabad says:

    Kindly post some User Manual, WS Tutorials/Guides and other installable (crack) files for ETAP 11. I think ETAP 11 is HOT topik for Electrical Engg.
    This is my Humble request to you to send me some informations at my e-mail Id.

  37. Ravi says:

    Sir it is very helpful & Thank you for giving good amount of knowledge, i request you to kindly send me the all the notes to my mail id, as it is very helpful & i cant access net when i require some time so i will have to carry hard copy
    request you to kindly send all notes in PDF mode to my mail id


  38. shiraz ul Islam says:

    keep it up

  39. Saikat das says:

    Thanks for efforts for us,your notes really help us a lot,i an glad to see few more topics on machine design and fundamentals.again thanks a lot.

  40. Chinmoy Sen says:

    I am in mech. engg. I have many query in basic electrical. Your articles helped to understand basic funda. Thank you very much.

  41. Kiran Kumar --- SYSTEM DESIGN ENGINEER says:

    Thanks a Lot for your data it has really helped me in my professional life, for every enthusiastic learner this data is very useful………! According to me think you are doing your level best……..!

  42. Inverters in chennai says:

    Awesome blog! keep it up.

  43. argha says:

    i am a electrical engg……this blog helps me a lot .plz upload more question answer article ,it is very helpful for interview.

  44. priyanka says:

    how voltage change from 11v to max .voltage in power transmission system??

  45. janahiram says:

    thanks.very useful

  46. THIS IS TREASURE :D, thank you :D

  47. pssrpskumar says:

    Thanks a Lot for your data it has really helped me in my professional life, for every enthusiastic learner this data is very useful………! According to me think you are doing your level best……..!.
    actually i need AC & DC UPS sizing calculations spread sheet in Excel format.please send as early as possible .this is my email :psrpskumar@gmail.com

  48. Kaveri Sudhagar>G says:

    Dear Sir,

    Your artical is very good & usefull. Pls add about DG Sets. Types of DG Sets & Different. Pls do needfull

  49. shahid says:

    one of the best website
    thank u sir

  50. Rojen says:

    Hats off to you Sir… Effort behind this is great…

    Thank you so much…. Very informative…..

  51. sami says:

    thanks a lot for all, please can i ask you for : line protection setting calculation :-)

  52. sundar says:

    Dear friend

    Nice details,, I need NGR details. can you post that

  53. Khin Shwe says:

    Thank you very for your Electrical notes.

  54. Unknown says:

    I am really thanks and salute 2 u………

    Good job

  55. aniket says:

    sir i want to know the distance b/w two pole ht an lt both

  56. Oswaldo says:

    thank you dude. for the information… greetings from El Salvador C.A.

  57. Arul says:

    Please provide me Electrical Panel Inspection check list that will be grateful to you


  58. Amal Kumar Maiti says:

    Mr. Jignesh Parmar, You are the great. One of the most powerful Technical Site I have ever seen.
    Every person will be benefited from you.

  59. Palanisrinivasan says:

    Could you please send as commend, how to select the suitable under/over voltage protection relay from different manufacturers for primary star and secondary 2VT open delta connection PT.

  60. I really seem to agree with everything that
    was in fact written within “Electrical Notes Electrical Notes & Articles”.
    I am grateful for all the information.I appreciate it-Lanora

  61. Nimesh says:

    thank you jignesh parmar. this basic information relating ele. engg.is very useful for every electrical engineer. and also thank you my ketul sir who suggest me to use this site……

  62. kalesh says:

    This is very useful information. Thank you sir.

  63. GAYA3 says:

    Sir can you help me to design a Current Transformer with basic requirements and the necessary calculation for designing it, with a best example…. i’m inreal need for the info. please help me….

    with regards,


  64. pravin mali says:

    thank you sir.u r proud of gujrat.

  65. pravin mali says:

    please inform me via mail about uptate and changes

  66. Pravin mali says:

    jignesh sir, i want know about 67-restricted relay for transformer protection.pls, give me reply.i am waiting.
    From:Pravin Mali

  67. Very nice post. I definitely love this website. Stick with it!

  68. mwadym says:

    Dear Expert,
    what is the effect of power cable laid in looping?

  69. vishal mullewar says:

    sir can you please provide some information about Transformer differential protection , stability , sensitivity of transformer differential relay, HV REF /LV REF stability & sensitivity.

  70. rahul says:

    Sir would you please give notes about Load choking..?

  71. m.uthandaraman says:

    there are very usful to many peoples who interested in electrical.. i have many douts.., in that one dout is.

    why we considered per unit impedance during the calculation of transformers operated in parallel? and its uses? give some exambles how the load divide depends upon their p.u impedance value of the transformers?

  72. Kiran kumarGudla says:

    Really superb sir,for your wholehearted support to all Elegant eectrical engineers..Hats off u sir………..

  73. Salinee says:

    this web page is really very interesting. Sir, can you please provide notes on generators..thanks.

  74. EDWIN RAYER G says:

    how can i find out the loss of transformer in kw

  75. Deepak Agrawal says:

    dear Jigneshji,
    can u provide me with some reactor sizing, for capacitors for hormonics prone area

    i mean, whats 7%, 14% reators, when what specs are to be used and all

  76. Aung Zaw Htun says:

    I want to know how to choose of neutral cable rating

  77. Pankaj says:

    Hello sir,
    it is helpful notes for electrical engineer…pls provided Electrical Testing notes on practical basis..like transformer testing, breaker testing, oLR testing, relay testing, micom relay testing, cable testing, etc. positive response awaited from u..
    thanking you,

  78. eass says:



    I need your reference:
    All manufacturer’s are followed IEC & IEEE standard for design MV switchgear at rated 40 deg. C ambient temperature. However, if ambient temperature increase to 50 deg. C, then How manufacturer should satisfy their clients (Client has been some current rating limitation bus bar as well as CB) technically. Please provide me details

  80. PK Goyal says:

    Dear Mr Parmar,
    You are one of the greatest, broad hearted and kind human being who believe in sharing the knowledge they possess as you will agree that the knowledge you have will be lost for ever when you leave this world. It will enrich the knowledge of others interested in the subject and immensely benefit the mankind in its pursuit to excellence.

    I have come across with your articles while looking to solve one of my problems and I seek your wise advise in the matter. We have one tea manufacturing industry near Siliguri in the district of Darjeeling (West Bengal). We have taken up the task of efficient utilisation of electricity by looking into each and every factor affecting the electricity charges viz., contract demand, actual requirement, power factor, load factor, installation of required equipments, earthing, overall electrical wiring etc.etc., We have no idea about these and other factors affecting electric consumption. For this we need your guidance and like to know as to how you can help us or guide us in the matter. This is a business requirement and therefore, it will definitely be on cost basis.
    Waiting to hear from you,
    With regards,
    PK Goyal

  81. swaroop says:

    A dought on carbon brushes, can we use commutator carbon brushes to slip ring induction motor.


    Dear Jignesh parmar,

    I am working in 2MW Photovoltanic Solar power plant as Electrical Engineer (O&M), these plant generate power at day time & take power (Import) at night. At night Import power is used for plant lighting only as generation stopped after sunset, At the time of Import power, we have a light load (near about 10KW), due to which our power factor is Low. & Electricity board charge panalty for low power factor. How can i improve power factor to 90-95%.

    Thanks & Regards,
    Leeladhar kashyap

  83. Ramu says:

    what happened for my query dated on 22-10-13

  84. KESAVAN says:


  85. Sukanta Bhowmik says:

    I want to know about tranformer

  86. Rajaram Mahadeo Mane says:

    I want to know about Lighting arresters.

  87. soe tun says:

    I have a problem while downing electrical tools,what should I do then?I want to get all of excels,plz advise me

  88. gaurav says:

    Thank you very much………….
    Information is very helpful for us

  89. Renganathan says:

    Sir I need to know different types of relay operation for protection of transformer

  90. Swapan says:

    Dear Sir,
    I saw almost all of your posts those are very helpful now I request you to post the different cable sizing processes for domestic, commercial & Industrial Electrical works for practical purposes……

    Swapan Kr. Bera, kolkata, West Bengal, India

  91. m says:

    what is need for generating the power are 3.3kv, 6.6kv,11kv,66kv ?

    in terms of form factor why?

    any special in form factor ?

  92. geetha sundar says:

    need for form factor?
    why generating voltage are 6.6,33kv,11kv?

  93. geetha sundar says:

    why our country frequency say as 50hz? any reason
    in others are 60hz … i am totally confused for silly questions

  94. dear sir,
    i want to know abt the windings of cieling fan and complete information about the structure and working of cieling fan

  95. please tell me difference between mcb/mccb/elcb/rccb

  96. P.Koteswar Rao says:

    df/dt settings required please

  97. amirnangial says:

    there is 11kv/230 single phase transformer ,one of secondary conductor is grounded why?

  98. amirnangial says:

    in overhead system, most of fault are single line to ground why?

  99. saisiva says:

    guruji u r great

  100. saisiva says:

    i think in case of over head transmission line probability of failing a line is high compared to probability to fail all line so single line to grnd faults are more

  101. saisiva says:

    sir why should capacitors be placed at 2/3 of feeder length from sending end

  102. faisal says:

    What is power factor sir

  103. Bhaskar Joshi says:

    Dear Jignesh,
    My capacitor bank always showing overload, i have checked all the contactor, fuse, and replace the controller but still the same probelm
    can you please help me what i should do

    thank you for your help


  104. Prasanta Das says:

    Dear Mr. Jignesh,

    I want to know the details about DG Synchronization? can u help me?

  105. Nand Kishor says:

    excellent work sir

  106. What’s up, I check your new stuff on a regular basis.

    Your story-telling style is awesome, keep up the good

  107. ashish dandale says:

    awesome sirrrrrrrrrrrrrrrrrrrr

  108. CHHABILA KU SAHOO says:


  109. jayesh.s. chauhan says:

    sir i want to know why always ‘ earth foult realy connected on ‘y’ phase”

  110. Ajay says:

    How to connect cable sheath earthing in case of core balance current transformer? Whether we have to pass it from CBCT or not?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


Get every new post delivered to your Inbox.

Join 3,539 other followers

%d bloggers like this: