I agree. Dad is a retired electrician and our house had a breaker with a high pitched noise when load was been applied for many years. He tested it, measured the temperature and was like "Yeah, it's just edging on the tripping point. No harm done!"

Don't watch The Killer then 🤣

Cemetery Gates

Very good points. I remember my granny replacing a light bulb with a double adapter, the bulb went back in one socket, and an electric iron in t'other. 😂 Happy days.

A friend a few years back bought a one bedroom flat in London, costing a fortune of course. He was stuck for money renovating the place. He focused on the bathroom and kitchen to spend. I told him he could cuts costs on the electrical system. I explained. Have *two* circuits with a very small and cheap Consumer Unit box. One circuit serving a 4mm ring and one 1.00mm lighting. Heating and hot water was a gas combi. I said Induction hobs are now available with 13A plugs. Ovens now have integrated microwaves (saving worktop space) being 3kW maximum. He was to have a dishwasher and washing washing. So, the ring to have ▪ The induction hob (3kW) and oven (3kW) off 13A fused spurs in adjacent cupboards. ▪ Dishwasher (2.2kW) and washing machine (2.5kW) off 13A sockets in adjacent cupboards. ▪ The ring fed four heavyish current drawing appliances plus an electric kettle. The rest was TV, computer, combi and phone charging. ▪ The 4mm was if the cable was cut for any reason the 32A breaker would protect the two cable legs and also if any imbalance on the ring. ▪ The ring was a distributed busbar. The likelihood that all four appliances would ever be on full power at the same time was extremely slim (diversity). He bought a reel of 4mm cable on a good deal as well. I suggested at least an RCBO, but an AFDD on the ring with an RCBO on lighting would be far better. He went for the AFDD costing about £55 over the RCBO. Works a treat. Very safe. Never had any problems. It never costed a fortune - saving quite a lot of money. Look at the Continental main boards in one and two bedroom flats - huge and full of radial circuits. Looks like what you may have in a small school. Unnecessary.

Ring circuits have been widespread in the UK for 75 years. They have been found to be *very safe.* The British G Type fuse-in-plug was to protect appliance flexes, however became an _enabler_ to use final ring circuits. The final ring circuit is ingenious in its simplicity. When used with the British G Type plug the ring is a busbar run around the house with distributed fuses at each appliance. There are many *advantages* to rings: ▪ Cheapness, as smaller easier to install wires can be used; ▪ A large number of sockets can be off one cheap to install ring; ▪ Having the same number of sockets using radials would mean multiple radials and multiple extra breakers at the main panel. Far more cable, expense, labour and hassle; ▪ The 32A breaker and 13A fuse in the plug ensures safety; ▪ Portable plug-in appliances on a ring cannot exceed approx 3kW. Some plug-in ovens are on rings; Rings usually have a 32A breaker at the main panel - can be a lower value; ▪ Using push-fit *maintenance free* Wago type connectors to connect up the ring adds safety, as not being screwed connections they do not work loose. The ring's current does not run through the socket terminals (this applies to radials); ▪ The British plugs enable rings having a _max_ 13A fuse in them - can be as low as a 1A fuse in the plug to suit the appliance and flex/cable. Small flex and appliance? Then a smaller fuse; ▪ Rings in the UK are limited by square metres of floor space, with no limit to the number of sockets on the ring. 100 square metres of floor space with 2.5mm cable for a 32 amp final ring. The cable can be 4mm, which is advisable in an unbalanced ring drawing high current loads; Less voltage drop on long cable lengths as voltage comes from two ways; ▪ Two ways for the earth wire back to the main panel, increasing safety levels. Radials are also used in the UK. Rings are not mandatory, but used because they have proved to be generally trouble free and safe. They can be installed using *rule-of-thumb.* These days a ring will be on an RCD, RCBO or AFDD - these now are becoming DP, so safer again. AFDDs are now mandatory in some socket installations and _recommended_ in all installations. AFDDs raise the safety level. If an office wants more socket outlets for extra desk computers. It is a simple matter of extending the existing ring with the extra sockets as the current draw is low. Cheap and easy. If radials are used many radial circuits would be needed, which may mean an extra consumer unit, breakers, wire etc, then far more labour. Some *disadvantages* are: ▪ Rings are more difficult to fault find. But electricians have no problem once the ring is fully understood. The ring can be split at a socket then tested as two radials; ▪ Another is that if a number of high current drawing appliances are on one side of the ring, say nearer to the main panel, most of the current draw may be down one cable leg of the ring with the cable rated below the main 32A breaker. An unbalanced ring. 2.5mm cable is rated at 27A max. Although tests have proven the cables do not exceed their current capacity in the vast majority of cases, just an imbalance in distribution of the two cables from the main panel (consumer unit). *Good circuit design will prevent this, negating this* *_disadvantage._* Balanced rings can be installed by daisy chaining to _alternative_ socket outlets on the ring. That is the first appliance will draw from one side of the ring, the second socket will draw from the other side, and so on round-robin. Or use 4mm cable to the point where heavy current drawing appliances are, then 2.5mm for the rest, if it is that troubling for some. Using 4mm cable on one side of a ring and 2.5mm on the other, is still cheaper than a bunch of radial circuits. Overall one ring is superior to a bunch of radials needing their own breakers at the main panel. They are simpler, cheaper, being proven to be safe and worked well over the past 75 years. Using the new AFDDs on rings, which are _recommended_ and mandatory on some installations, gives a *far higher* safety level. You will have to give a very convincing argument against rings. I have not heard of one yet.

Vanilla chaiiiiii

Are you drunk?

Great idea! Totally agree. It’s been gone through with a fine tooth comb now 😁🙏🏼

Great idea 💡. Never thought of that before, thank you!

Any time!

All new circuits in the UK houses have required RCD (GFCI) protection for some years (and kitchens/bathrooms circuits for a few years before that). That used to be via separate RCDs protecting multiple circuits due to cost, but the trend now is (thankfully) to separate RCBOs as the costs have plummeted and people have now learned their value. As for AFDDs, then combined RCBO/AFDDs are still extremely expensive (about £100 a circuit). European spec AFDDs are not the same as US ones. One particular difficulty is that there is no means of testing the AFDD device on-site. The test gear used in the USA for AFDDs don't work with the ones available in Europe. One difference in the UK is that the great majority of properties are made of masonry, so there are differences in the fire risk compared to wooden buildings. IN any event, AFDDs have to be considered and they are compulsory in some types of property, such as care homes, where the occupants are at particular risk and they are meant to be considered.

@@TheEulerID AFDDs are *mandatory* in high rises over 6 floors (all flats in the block), care homes, etc, but only on socket circuits. They are strongly _recommended_ on all installations. Common sense must be used fitting them on high current drawing circuits a must. AFDDs are around £80 a unit, dropping in price as uptake increases.

@@johnburns4017 I alluded to AFDDs being compulsory in certain sorts of building (although BS7671 is not a statutory document). As far as other buildings, whilst they are recommended, the wording does not say strongly. "For all other premises, AFDDs conforming to BS EN 62606 are recommended for single-phase AC final circuits supplying socket outlets not exceeding 32 A."

@@TheEulerID That sounds strong enough to me.

@@johnburns4017 you don't just get to add your own adverbs. If they meant strongly, then they would surely have said so.

A lot of the reason for smaller breaker boxes in the UK is because the homes are considerably smaller than the typical North American house. Thus there is an onus on keeping them small and also tucking them out of the way, much to the annoyance of electricians who often have to work in confined spaces.

I live in the US in a house with 120/240 open delta 3 phase. I have both US style panels and din rail although the din rail panel which is in the shop is not just circuit distribution, but controls (relays, timers, a PLC, 24vdc power supply, etc). Not typical for a house though. The reason the panels are so big isn't because they're split phase, but rather the high amperage and number of circuits. A 100a panel is about the biggest small din rail panel in the UK. Above that they are 3 phase and look just like the panels in the US, but with DIN breakers. ABB actually makes a US market DIN rail panel, it's called the ABB Proline. Completely finger safe with insulated busbars. Working live is like plugging appliances into the wall. Only comes in 3 phase versions, however. I'm planning on using one when we go from 100a Delta to 200a Wye, when the power company is ready to run a new service drop to the next pole over where there is a Wye transformer set.

Thanks mate!

Thanks 🙏🏼😄. These sort of videos are great for apprentices too

Always a pleasure

Good call!

Glad to hear it

Many thanks!

Absolutely! Thankyou 🙏🏼⚡️⚡️

Thanks for your insight

@@corymac There was a big review of all the building regs in WW2, 1942, in anticipation of the post war building boom.

Very kind 🙏🏼⚡️

🙏🏼🙏🏼🙏🏼

Thanks Mark! 😁

Only one end of the steel wire armouring needs to be earthed, for the same reason only one end of a copper water pipe needs to be earthed. Sometimes the steel is used as the CPC, so of course would be terminated at both ends.

There is nothing wrong with it as far as the regulations go, although it might mislead later electricians as to its role and hence be misidentified. It might also be incompatible with connectors made for 1.5mm cable. You would not, for instance, want to try and connect 4mm^2 cable into a ceiling rose.

Thanks! 😃 We have a great editor!

Thank you kindly. If I catch a finger that’s one less annoying KZfaq sparky at least

Am I getting younger and fresher with every video? 🤣

Lmaro 😂

Not so much the cable that is the issue, it’s more that terminals on a lighting circuit won’t be made for it

It doesn’t matter. Which is why it was left, it’s just unconventional.

@@corymac Thank you. My background was before I switched to IT in the BBMS/Switchgear design and prototyping for telecom and oil industry. So I am not familiar with home wiring and regs, especially past 16th edition which was when I changed career. I really enjoy watching your channel and often wonder why I moved out of electrical.

Ceiling roses and most terminals on light fixtures are sized so you can’t oversize the cable , 2.5 is oversized for lighting never mind 4mm

@@corymac The bigger the cable, the better. If lighting then have it on 6A breakers.

They sound like AFDD’s, but best chat to the electrician who installed them 😃

@@corymac cheers it's a council house so like talking to a brick wall 😂

Or even picked up a crap reading when testing

Im assuming as it was only 1 socket with the higher reading, that is just a spur from the ring, if it was multiple high readings then it would be a mess of a ring. As it was one, its safe on a 32A

An electric space heater can easily draw 3 kW. I can imagine wanting to use a portable one of those on top of whatever other tools I might use. Also, some people put tumble driers into the garage if they don't have space in the house.

@@TheEulerID Yes but it doesn't draw it constantly but cycles. If we take the garage/workshop I have as an example. The outlets are on 2 16A C, then theres the third for lights that's just a 10A C. I have never managed to blow a fuse even if welding. The hole property is powered with 25A mains (by it being 3 phase) but could by all means go down to 20A. Even the latest factory the company was involved with (120 000m2, that even has 16 10kv transformers) only has 16A outlet circuit and 10A for lights. Heavy machinery ofcourse has there own circuit. Thats why I question why a small house in the uk would need 80A main and 32A for outlets.

@@Iceeeen You can question all you like, but in my kitchen and utility room I have the following devices which are plugged in an connected to the ring circuit downstairs. A fridge/freezer, a 3 kW electric kettle, a 1.4 kW microwave/oven, a 2kW dishwasher, a 3 kW one-cup water kettle, a 2kW toaster and a 2 kW deep fryer. Of course, those are not all used at once, and not at full power, but if they were all on a 16A or 20A circuit, then there would be a good chance of nuisance trips. Then you have to have multiple circuits in the kitchen, and have the wrong combination of things on a particular circuit, and happen to turn on the wrong combination of things, then you can get a nuisance trip with multiple circuits. The fixed, 6 kW cooker is on its own 32A circuit. As for a detached garage as I have, then it is easer to have a single 32A or 40A RCBO circuit with a 6mm^2 cable with a cheap and small garage CU with a couple of separate lighting and socket circuits there. In essence, by having a fuse in each plug, it not only provides better protection than a circuit breaker alone, as it can be rated to the appliance and, importantly, the flexible cable used. A table lamp cord is not properly protected by a 20A breaker for instance, but it greatly simplifies wiring and allows householders to plug in what they want and where without too much danger of a nuisance trip. If the gas central heating has failed for example, they can plug in a couple of portable electric heaters until it's fixed. It doesn't much matter if they are in the same room or different ones. As for total power requirements, some houses have 10 kW electric showers, and a few more than one. Those are 40A each. Also, for those that don't like ring circuits, 32A radials can be used using 4 mm^2 cabling. I should add that it's also quite common to have one socket on a 40A cooker circuit. Three phase wiring in domestic properties is very unusual in UK domestic properties, and it does complicate wiring, especially if 3 phase appliances are used. What might drive it is electric vehicle chargers and the replacement of gas central and water heating with heat pumps. I will probably run a 5 core SWA cable to my garage to allow for a future 3 phase charger which can go to 21 kW rather than the 7 kW limit on single phase, although it would, of course, require the local electricity supply company to provide that via the three phases in the street.

​@@TheEulerID Many think heat pumps will consume high currents. They will not. A 6kW heat pump can replace an 18kW gas boiler. The COP of 3 sees to that. They also operate at lower temperatures so will be running longer, like on temperature setback overnight. Three phase in average UK homes is madness. Unnecessary.

@@johnburns4017 even 25A sustained is still a significant extra load. Also, 3 phase allows the use of 21 kW EV chargers, or multiple 7kW chargers, which, when combined with smart charging is a great way to soak up excess capacity from intermittent renewable. Some new houses are being equipped with 3 phase from the start, and it is normal practice in countries like the Netherlands and Germany. Are you saying they are mad?

They test because it is what is done.

IR tests are done on all circuits, not just ring finals. Not because of smaller conductors (and of course a ring uses two lengths of thinner cable rather than one length of thicker) but because separation of conductors, using insulation, is important/essential to all installations. It can pick up all sorts including damaged insulation, heat damage, etc.

That’s cool 👌🏼

@corymac yep but I did not know that you can us a American panel box and wiring and outlet and switches in the uk

@@wolf3five You can. I would not thought. They are huge and look like something from the 1950s. European row panels are superior. Look at Schneider.

@johnburns4017 but the European panels are so small and not a lot of room where the homeline 40 panels have a lot of room and you have more breaker space

@@wolf3five You do not know what you are writing about. Look at the French Schneider panels. They even have comms as a part of them. Look and learn.

Think they say it's allowed because any plug connected to it would be have a 13A fuse in it.

I had an Irish electrician confirm to me that ring circuits are allowed in Ireland, but they are a lot less common than in the UK. A bit of research appears to confirm that. I'm never quite sure what the advantage of the insulation is in T&E cable apart from not having to sleeve the earth. If the insulation is failing in a cable, it doesn't much matter if there's one more layer to the CPC. A single spur is allowed on a ring as the theoretical load limit of 26A on a twin socket is below the theoretical cable rating. In practice, it's a very unlikely scenario and, for that matter, twin sockets in the BS163 standard only have to withstand a 20A continual load for 4 hours without a significant heating effect.

🤣🤣🤣🚽

I think you’re missing a trick with builders ring t-shirts.

Our more recent panels in the US have shrouds on the incoming lugs so they are safer than they used to be. And ring circuits are definitely worse than the split phase system here. Just about every UK electrician video shows checking ring circuits to make sure they are intact. The split phase system is essentially a 3-phase wye system with one fewer wire, it's hard to get wrong and if you do you'll know instantly.

@@eDoc2020 Most UK elections prefer Radials for outlets and lighting circuits are Radials anyways! your lighting circuits are crazy! flats and lamp failures cause weird lighting issus

Too true

Genuine question. What's the issue with Hager AFDD? Thinking of asking for some on a new CU.

@@wizgha1987 David Savery couldn't get one to trip, even with very obvious series and parallel arc faults. Basically a case of being too smart for its own good.

Ouch. Which brand are considered good quality? And can you swap other brand AFDDs on a CU? E.g. I'm thinking of requesting a Hager CU (I'm assuming they're considered top quality) but different brand AFDD - is that possible?

@@wizgha1987 You are not meant to mix different brands in a CU as the manufacturers haven't tested them together and as such it would probably get some sort of fail on an electrical safety check. Whilst a lot of that smacks of protectionism by manufacturers, there is the real issue that the bus bar locations are not standardised and there can be real issues with that between different brands.

@@TheEulerID Perfect explanation, thank you!

I often do this

😂😂😂

The conductor size isn’t the issue here per se, it’s the things that will then go along with it, such as terminal sizes on light switches and sockets being too small to receive 4mm, bending radius for t&e entering little light enclosures etc

@@corymac When using 4mm (or 2.5mm for that matter) on a ring or radial, use lever Wago types of connectors in the backbox to take the current load of the spine. Then from the Wagos use 2.5mm flex to the socket terminals. Then current only runs thru the socket terminals when it is in use. Then no stress on the socket terminals as the socket is pushed into the box. Works a treat. Also quicker. And great for 1st fix testing - leave the Wagos in place ready for the 2nd fix fitting of sockets.