VOLTAGE DROP CALCULATIONS IN 3 PHASE INSTALLATIONS AND SINGLE PHASE CIRCUITS FROM A 3 PHASE SUPPLY
We’ve had lots of requests for a video on 3 phase voltage drop in electrical installations.
Lots of factors can affect this, the position in relation to the origin, cable sizes, types of cable and the loads being serviced to name a few.
In this video we will give a basic introduction to the subject, keeping it simple so that everybody can learn.
We will look at the various formulas involved, show you how easy they are to use and then give you a 3 phase scenario in which we work through everything step by step.
At the end of the video you should feel a lot more confident in performing these simple and basic calculations.
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Love the way you explain things - keep em coming !
Thanks, will do, and lots more to come. Dave.
This is probably the best electrical KZhead channel.
Nice of you to say so, your comments are really appreciated. Thank you. Dave.
Dave, thanks for the lucid and detailed examples. I was actually looking forward to calculations for 3 phase supply. Best wishes.
Thank you, great support. Dave.
It's awesome, Simply the best
Great comments, appreciated. Dave.
Excellent 👍
Thank you. Dave.
I'm here again. Thanks for sharing it with us
You keep coming Daniel, appreciated support. Dave.
Great information
Thank you, lots more to come. Dave.
love your videos ......
Thank you. Dave.
Well done, However I was calculating the Vd on single and then spotted as other people also spotted the calculation. Thanks for superb videos
Yes, you are right. One of my typos. I'm having calculator lessons next week. But look on the good side, it proves you are on the ball. Thanks for the feedback, it is really appreciated and thanks for keeping me on my toes. Dave.
Wow super
Thanks. Hope it was useful, Dave.
Great work as always and in a real life scenario ...would change the 4mm t and e to 6mm giving 1.9% Vd saving on cost for customer lol...but just showing i understand :)
Great comments, thanks. Dave.
your explanations are 5 star ,i am enjoying your work keep it up. now my question , HOW DO WE CALCULATE VOLTAGE DROP OF CABLES INSTALLED IN PARALLEL
Appendix 10 of the Regs book is about parallel cables. Thanks for watching and for the great comments, appreciated.
Great video as always . What is the difference between the bs7671 regulations and the on site guide ?
The on-site guide is a mini reference book with user friendly sections that are based on the actual Regs,
Hello Dave, thanks for the video. I am wondering the difference between the one you mentioned and the another formula 2 x K x I x L for single phase, 1.732 x K x I x L for three phase, whereas K is 12.9 for copper and 21.2 for aluminum? Thank you
It depends on the csa of the cable. Thicker cable has less volts drop. Three phase has slightly less volts drop, take a look at table F5(ii) in the OSG. p176.
sorry, I am still confused, which formula is for thicker cable? and which is for thinner one? my understanding is the formula 2 x K x I x L could be used for the cable size from AWG #12 to 1500MCM. Does is mean the formula mentioned in your video is used for the cable size smaller than AWG #12? I would like to read OSG. p176, but what is OSG stands for? thank you@@learnelectrics4402
Big Thank you Dave.A bit of typo in the first example .Vd1= 4.4 instead of 3.52.Excellent I really enjoyed working out the maths .Dave what is the difference between z and x and r plese? Thank you.
Yes, well spotted. It seems everybody has noticed this. I'm having calculator lessons next week. A couple of other chaps have asked me to do a video on the rest of the tables, its now on the list to be done. Thanks for watching and keep making sure I stay on track, appreciated. Dave.
@@learnelectrics4402Dave you are best of the best.We all appreciate you.Dont think you need calculator lessons .please just keep educating us .Thank you so much.
Simply helping the few youngsters that are going into the Trades and not the WOKE production line factories aka universities ( until now, not S.T.E.M)
Thanks for watching, appreciated, Dave.
Hi Dave could you do a video on Faraday's law
What! All of it? OK then, its now on the list.
@@learnelectrics4402 which list is this and can you provide a link please
Can we also use the (R1 + R2) x L x 1.2 /1000 for the three phase and use the (R1 + R2 ) x L x 1.2 /1000 to do the same calculations independently. Then calculate the % for both the 400 v and the 230 volt independently then adding the total %
Why are you using R2 in the calcs. This is nothing to do with the earth conductors. This is the Line conductors and neutral as we are calculating Voltage Drop in a fault free installation, hope this helps. Dave.
Sorry dave meant the R1 and Rn not R2 as i had stated.
how you sum three phase vd to single phase vd i thinf first you must convert 3ph vd by divide it 1.73 then you sum thanks
Thanks for watching.
Is Ib 80A per phase or across all 3?
Each phase will be 80 amps. Thanks for watching. Dave.
Great video but I believe the total answer to be 2.73% on the first example using 4.4v instead of 3.52v
You are correct. A couple of you have spotted that. I must learn how to use a calculator. Thanks for keeping me on my toes, Dave.
@@learnelectrics4402 You are still our master regardless a few tiny mistakes!
Think there’s a mistake at 10:26
I second that. The Vd1 volt drop should have been 4.4V not 3.52V
You're right. Where on earth did I get 3.52 from. But it proves you're paying attention. Thanks for spotting that, really appreciated. Dave.
Yes it should, well done. Thank you. Dave.
@@learnelectrics4402 you just got 2 and 5 the wrong way round, easy done
@@learnelectrics4402 really enjoy your content by the way, one of the best channels on UK electrical learning 💪