EASY VOLTAGE DROP FORMULA and CABLE SIZE CALCULATIONS – ALL IN ONE - NO BOOKS – NO TABLES

We’ve been asked by many times if the voltage drop formulas can be made any easier.
Some say that the tables just confuse them, there is too much going backwards and forwards in the book and so on.
So what we will do in this video is what is called formula manipulation.
We will show you how to combine some different formulas that we might already know into just one formula that works better for us and is easier to use. Especially as this method uses no books or tables.
Everything is self-contained within the formula that we show you.

This video is No.126 on our YouTube channel where we have videos on a wide range of electrical topics.

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Always work safely, electricity can be dangerous. If you are unsure, stop and seek advice.
This video is provided for guidance only. Every electrical situation is different, please check and ensure that you are applying this learning information to your own individual circumstances correctly and safely. If in doubt, stop and seek competent advice.

[gbelectricks]

I’ve been in the trade for 26 years, and this is a regulation!!! Never seen this before 🤷‍♂️
Thanks for sharing your knowledge Dave😁👍

[NicoleBritnell]

Been on an adult course to become an electrician for over a year now, how and why have I not found you before? Brilliant resource, definitely subscribed and will now be watching all your vids, thank you so much

[MS-Patriot]

This back pocket maths beats the complicating scholars at the IET. Brilliant 😉

[jmsule]

Thank you LearnElectrics for the continuous value creation. Very helpful resources

[mth]

In preparation for my BS7909 exam, I was up at 1.15 this morning, watching this presentation. Absolutely superb. Made complete sense of the voltage drop calculation and, at a stroke, turned the entire calculation process into a thing of beauty, in it's simplicity with this new approach to solving the problem. Thank you to all those involved.

[simonharwood]

I iterate the below, just about to sit my 2391-52, choose an online course provider and struggled to get explanations of calcs from them. Fantastic resource you are providing, well delivered. It seems so simple!

[babangidaciroma]

Absolutely cracking 👏 how i wish i knew this channel 4 years ago when I was in college, its could have made my life much more easier. Keep it up

[PINOYcoolers-udyz]

The lecturer is brilliant as he clearly explained step by step, worth watching, super understandable and highly recommended!☝😃❤

[dimitrisblane]

Thank you.
That's the best and only video anyone needs to understa d voltage drop calculations!!

[bijay]

Cant thank you enough for this knowledgeable explanation ..Didnt learn all this in 3 long weeks of virtual lesson than what i learned in 16 minutes.Really appreciated

[chrischaralambous]

Hi Dave. I would just like to take this opportunity to say that you are a genius. This video has helped make life so much easier when trying to work out voltage drop and for aiding in the selection of cable size. I have been experimenting by using different figures in the calculations (ie. Cable length and Power rating) to see how much leeway one would have before having to increase cable size (CSA). This also gives you an idea of the load tolerance the cable selected would be capable of. Thank you again for making these videos.👍👌

[trevorlewis]

This is eplained so clearly and all of these videos are such a great help to me, thank you!

[tommythai]

A Brilliant resource broken down to something I can finally understand, a cracking channel Thankyou for your content!! 👍😄

[danielteyehuago]

Wow! This is very informative, thanks for sharing it with us Dave. It worth it and the best tutorial on the topic for me.

[abdulhaddad]

That's absolutely very helpful and very useful thank you

[MrDanTrials]

Brilliant! Needed to run some cable for a piece of equipment in my workshop, and this video was very helpful, thank you!

[DaveH-zlvd]

Which max volt drop figure should be used to determine the supply cable c.s.a. if the cable is to be installed from a house consumer unit to, for example, a garden shed that will contain lighting and power sockets?

[mohamedbaghdadi]

Dave be honest with you are brilliant Many thanks for your explanation.

[Ibrahim-vttz]

amazing teacher brilliant english good person thank you

[malachygallagher]

So easy to understand your explanations Dave!
Brilliant!
Regards mg.