CABLE SIZE CALCULATIONS – ON-SITE GUIDE APPENDIX F – AMENDMENT 2 – USING THE TABLES – MAKING CHOICES

The On-Site Guide is a useful little book, packed full of information. But sometimes, working out what it’s telling us can be difficult, and not just for new starters in the trade.

Take this question for example … a frequent question.
I’ve seen this formula in the on-site guide, what does it mean?
And it looks complicated, how is that going to help me?

In this video we will look at Appendix F of the On-Site Guide, a very useful appendix that helps you to select the correct size cable given the various installation conditions. And we show you how to use Appendix F to find the answers.

Almost everything that we do to a cable will cause it to heat up, even over-heat and become damaged. Choosing the right size cable is therefore in everyone’s interest. We show you how to make the right calculations with fully worked examples so that understanding and confidence improve.

What matters most is putting the right cable into the installation from the outset.

This is video number 214 and to view all our videos type in LearnElectrics all one word into the YouTube search bar.

Visit our YouTube channel where we have many more videos on a wide range of electrical topics.

[Chrisking]

give this man a medal. no one is doing it like dave. thank you dave appreciate all your hard work

[beskras]

Greatest Guy on Electrical learning videos. Thanks for the hard work

[francoistoumany]

Thank you Dave for helping us to remain technically minded as we appraoch each job. It's always a good reminder to give attention to how we design each circuit to make sure that it complies. As always much appreciated and keep up the good work. 👏🏾

[ragnor]

One of the best Elec tech sites on the web helped me understand how to wire sockets & lights into my son's ring circuit house which I had not come across before although I was competent to carry out all the work myself

[danielteyehuago]

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

[stegra]

A handy tip that's stuck with me since I was told it about the < & > symbols is that the < looks a bit like a squashed L (for less).I'd never had difficulty with them but this is just saves that bit of thinking.
Also, when using a calculator, the = button is your friend. So 20÷.88= (then) ÷.725= gives the answer without the additional step or using M+ and MR.
Thanks again for your incredible content.

[stephenl]

Thank you you are brilliant at this, I really appreciate what you do 🙂

[simplymiswak]

This video is amazing! Keep up the good work because I’m learning a lot.

[davidpatterson]

Thanks Dave—informative video, and very understandable graphics

[Roq-stone]

Another great simple elegant presentation.

[Grassislong]

Hi great video. I am currently doing design project through college and i have the exact issue that you’ve stated in 14:00. my I n is greater than my I t due to the 25c ambient temperature (which is required in the spec).

my understanding is that I t should be bigger than I n, under all circumstances. so how can i get around this issue to change the values and make the calculation work? really hope you can get back to me on this 😅

many thanks Daniel

[SuperCwiczenia]

Another great simple elegant presentation. Super @:)

[brianhewitt]

Excellent, correct design is always very important 👍

[MotherboardRepairs]

Great work 👍, I have a question what about Iz as i am getting it mixed up with It.

[ranazayed]

Thanks for the video, where can i find the guide ?

[terietaietawa]

Very useful and informative video thanks

[kristianbarrett]

Fantastic tutorials keep up the good work 👍

[mehdikhodabakhsh-fbez]

Brilliant explanation .but just wondering where about in question said what reference method is that.
Thanks

[david-ipcm]

Great vid! Quick q.. for question 1 why is the ref method C and not 100? ref method 100 mentions insulation doesn't exceed 100mm for which it doesn't as it's 50mm? thanks!

[AndrewBaker-zr]

Hi Dave
Can we please have a video about installing single cables for lighting circuits in steel conduit and how we prevent Eddie currents, thanks for everything mate