Відео

I'll second the first comment (genuinely). One tip for you if I can. When filming yourself, keep the eye level on the top third line ('rule of thirds') not in the centre👍

principle should be for a metallic exposed part connected to the installation. And RCD at 30mAl provides required protection.

Adibiatic equation. That particular one is for correctpy sizing the protective conductor. Can also be transposed for thermal withstand under fault conditions where T= S²K²/I² I always loved the matatical side of electrical engineering. If you can understand that then you can understand where a lot of regulations get their figures from These videos will be golden for any learner or as a refresher. Keep up the good work! 💪

Great video, thank you. What would the overall maximum demand be across all 3 phases to record on the certificate for the example you gave?

I was hoping you would have made it a lot clearer. Sorry to say it wasn’t very clear

6K views over a 2-year-period and nobody bothered to thank you for your tips... Thanks for these, will write them down and keep them in mind.

C3- enclosure made from non-combustible material C3- No RCD protection on socket outlets (C2 if serving outdoor equipment) C3-No charts/Labelling C3- No RCD protection on lighting C3- No RCD protection on circuits serving a bathroom/shower ( could be a c2 if no supplementary bonding where needed, wrong IP rating of equipment in zones)

Regarding unidirectional RCD on a Solar install I would code a C2 as it would be dangerous under fault conditions. Great point

All manufacturers will make the required breakers. Or go out of business. This is obvious.

thanks for the clarifcation

Please james provide sca for armored cable also provide examples,will you please

The fact they’ve used fire retardant expanding foam suggest to me, their intention was to in the event of a fire within the consumer unit, to contain it.

Clear as mud,you are just reading the regs,not giving any useful information

Yep, I know that already 😂

But would the armour and earth cable be in parallel anyhow so that is what you would use surly

What size main earth if its TT- tails 16mm? I done a eicr- it was 10mm to the rod- it was clipping direct to the brick work and then went under ground for a bit. I assumed it had to be 16mm reading table 54.1 . As there is no mechanical protection on it and goes under ground for a short way. Please can you let us know your thoughts.

Thanks for the video. You stated that in section 5, k1/k2xs, that its for 2 core 2.5. How would I adapt it for a 4 core 2.5mm 3ph swa ?

Hi James, quick question. In terms of the three phase calculated, if your completing a new installation certificate, would put max demand highest phase or the total max demand of phases?

I can’t understand why your channel isn’t growing. You are one of the most informative designers on UA-cam chap - you have a Great way of making thing simple. spark since 1980

Thanks James. Very informative.definitely need more info on these.😎👍

Not sure if if this is a dumb question, but when we do an EICR on a TT install with an “all rcbo” board. If you have 1x solar PV circuit connected on a uni directional rcbo. Doesn’t this mean you just need to swap out 1x uni directional device fitted on the solar PV circuit, for a bi directional device? Or do you swap the lot out? How about EV also, stand alone battery storage or ups? Do these all now need bi directional?? RCD considerations are becoming more of a ball ache… but look on the bright side we have less testing on the bloody things now!!!

Legend

If i have a circuit thats protected by a 32 amp b type rcbo and the measured zs is say 1.87 ohms can i mark down on the sheet that its getting used as fault protection aswell so the max allowed is 1667 rather than 1.1 ?

awesome!!! well explained 👏

Please see the link to the longer video ua-cam.com/video/NI6rfqwmy5U/v-deo.html

Seems from internet digging to be 1920s/30s.

Thank you

Great info buddy. Only just come across yourself. was Looking for info on using swa as the cpc as changing my fuse box in the garage (2 core 2.5mm cable already buried and under concrete lol)

Best vdo Sir

Can't you just measure the Line and Armour seperately and add them together or measure the Armour end to end and approximate the distance and divide to get a per metre value to see if it complies Zs , R1+R2 etc...wise

Just read an article on the professional electrician website, dated 20 Feb 24, that states "Cable entries, such as those often used for back entry into the consumer unit must be provided with suitable sealing methods and may include intumescent gaskets, grommets and/or fire sealants to maintain the degree of fire integrity." The article is called "Metal consumer units in an installation forming part of a TT system earthing arrangement | NICEIC"

Hi James thanks for the video help me a lot, one question if I’m using a 2 core armoured and the steel as the cpc how do I calculate my r1+r2.

really useful, thanks~

This is not totally correct. You can do electrical work in a Bathroom/Toilet providing it is not a new circuit and that it is outside of the zones.

Thank you, James.

Should be on the incoming mains

What about caravan home hook ups

Finally someone know how to explain this! Just one question. Where do I get the Ipfc=3.2kA? Do I ask the DNO?

If circuits have a rcd fitted ,are the Zs test readings important, if under 1667 ohms is a acceptable pass.?

It does surprise me that there isn't some stipulation, whereby if a CU is mounted onto combustible material like wood, that cable entries, especially rear ones that are bigger overall, don't have to be sealed in order to stop the spread of fire into the wood.

Would literally take two seconds to shorten the flex or fit a batten pendant instead 😂😂😂

Please see the link to the longer video ua-cam.com/video/3oVwbmH22O0/v-deo.html

Thanks for this video James, to the point and easy to follow along. Much appreciated

Great explanation of a grey area Jim

When measuring Zs do you go by 18th edition book,or on site guide 80% rule.?