Is the size of the cable that’s been calculated the minimum size for just the cpc? Or does it mean the size of the cable that’s used for the installation TIA
If you have the DN O out to isolate the wires and are fitting Henley blocks anyway… why not install an isolator switch while you’re there? Granted that the customer would have to pay materials cost but presumably that’s still cheaper than having the DNO do it - or more possible - and it’ll save the faff for next time.
Break in the neutral or lost neutral. Tester picks up induced voltage between L-N because of the floating neutral. When a load is turned on the L is connected to the broken N through the load and when both are at the same potential the meter will read 0
Thanks for another excellent video. Inspired teaching! It’s really appreciated. The video deals with Ib <= In <= It. To find the correct cable size. No mention of Iz. An earlier video (251) described Ib <= In <= Iz to find the correct cable size. No mention of “It”. What is the difference between “It“ & Iz? Are they basically the same thing? I guess Iz represents the standard scenario where no special rating factors apply? Eg no insulation. And “It” replaces Iz (as a way of finding the required cable size) when there are specific conditions eg grouped cables or insulation? Thanks again!
Thank you so much, you are one of the best, your channels is one of the best channels on electrical subject, am so grateful, your videos helped me on my 18th Edition exam and other level 3 exams, please, do you videos on level 4 courses?
If the toilet is in the zones measured from the bathtub then it comes under whichever zone it is in. Everything is measured from the bathtub or shower basin.
What I can't seem to find a good video on is... is it acceptable to put more than one circuit into one MCB? So many different opinions out there about it and when it can be done and when it can't.
Its not good practice to mix different circuits on the same MCB. But you will see two lighting circuits on the same 6A or 5A MCB where the combined load is less than the MCB rating. Think of that as a spur starting at the consumer unit.
Yes, this is a typo, it should of course be 0.2. I may republish this video. Meanwhile, this proves that you are on the ball, and I appreciate that, thank you. Dave.
Your examination centre, where you are doing your training, will have a prospectus and details of the books, Some centres will provide copies of things like the EAWR memorandum and other booklets for you. I would recommend that you have your own copies of the Wiring Regs, OSG and GN3 so that you can read and revise from them every day. Don't leave revision until the week of the exam.
Hi dave.. Just need to ask about the typical values we looking for when doing a test! like acceptable Zs and cable resistance etc.. Just need to know if there is any tables state these values so i can refer back to them when testing with thanks.. Again Thanks for the great effort and time given to create these educational videos. Best regards
There are lots of ZS videos on the LearnElectrics channel, take a look at the one on the link below. Put in LearnElectrics Zs in the search bar and you will find them all. Meanwhile, look at this one. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-MEXddmY61Qg.html
@@learnelectrics4402 Hi Dave. Thank you for your efforts and excellent videos. I do know that It is greater or equal to Iz but do not know how to explain it. Is Iz the value we get from the formula after dividing In by the factors?. The formula states the It is greater or equal to the value we get after In is divided by the factors and I would like to know more about Iz please if possible.
If I’m upgrading a bathroom extractor fan to one that requires a type A rcd do I need to replace the type ac with a type A or can I leave the type ac unplaced as regs are not retrospective?
Take a look at the video on the link below, it describes the differences. An original type AC RCD will still detect some types of fault on the unit. However, the Regs always recommend that manufacturer's instructions are followed for best protection. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-bOTberqGvQU.html
