Cooker Circuits Diversity, 15kW load, 32A circuit breaker. 

Amen to that.....

Agreed. And once the regs are confirmed and finalised, that’s that!!!! I’m fed up of regs changing, you never know wether you’re coming or going. The only reason the regs change is for some clown to justify his/her job: * walk into building* *hmmmmm..........what nonsense can we make up today just to piss everyone off??* *ohhhhh, I know,*

@@w415hyz if they didnt come up with new ass rules they would be out of job, so why you think they do it

A couple of points in this video I have had a disagreement with my assessor over the last couple of years......he nearly shat when I showed him this😂😂

@@w415hyz You forgot about £ that they earn from sale of these books😁

"every word you use has value and is not in the least superfluous" - oh yes some are - when he's in dry humour mode - which occurs a few times in his videos.

In this video, paraphrasing: "if you're the type of person who puts it in and just uses it for 20 years without cleaning behind it, this does not apply to you" (Which from my experience seems to be most people!)

Totally agree with every word!

TheChipmunk2008 - what’s this strange thing you speak of “cleaning”? 😂

I can only second that! Also very clear English and good pronunciation which really help if someone is not native speaker.

P JD You need to come to mine for a full Christmas dinner! Three ovens, eight rings and warming cupboard going full tilt. If the lights don't dim across South London it means I have forgotten one of the veg.

@@r.h.8754 22amps

@@spencerwilton5831 The old Christmas dinner fear. They will not be all on at once as thermostats cut in.

@johnburns4017 if they are all on, how long until it trips?

Well, a 10mm2 cable won't hurt anything... Except your wallet and your finders, I guess.

10MM is a BEOTCH to deal with in any normal accessory box. I agree with the person elsewhere in this comments section that says it doesn't belong in a domestic environment except as a feed to a specific outbuilding or second fuseboard. In which case you're not going to be terminating into an accessory box.. The number of electric showers that have exposed primary insulation outside the box either in the wall or roofspace because there's no physical way of doing otherwise even with a 47mm box... is countless

10mm is overkill, unless they have multiple cookers

6mm is the correct size if the cables are partially covered in insulation. You got to derate the cables based on installation method.

Is there not a regulation concerning box fill? I know the US version has a section specially addressing box fill and minimum volumetric dimensions.

Here here. John is an example of relying on books rather than foresight. I still remember his video on why it was pointless to replace rewireable fuses with the push-in resettable style. Except for the fact that a lot of pensioners can't afford to get a new dB and a full EICR.

you should always future proof it aswell, we dont know what kind of powerfull cookers we might get in 10 20 years

What is the total load of the oven? To trip a 32A circuit breaker in 45 minutes would require well over 40 amps continuously, which would be a heating load in the region of 9-10kW, which seems grossly excessive for any oven.

6mm cable is acceptable for 40A MCB (clipped direct)

@@jwflame I dug through the manual and it states it should be fused at 16A and has a max consumption of 2900W. I'll have to get a clamp meter on the supply cable to see what it is drawing in cleaning mode.

@@cambridgemart2075 Something fishy there then - if rated 16A and tripping a 32A breaker ! Faulty appliance ?

Has he replaced a traditional oven with it? (they often used a 13A plug onto the ring mai...err ring final ;) ) Kitchen companies are AWFUL for that... sell a customer a self cleaning oven without telling them 'you're gonna need an electrician install a dedicated 16 or 20A circuit. If it's on the same ring as the rest of the house (often in older properties without a dedicated kitchen ring) a constant 2.9Kw load might be competing with other appliances.

Myhippocampus I tend to do rings for utility and kitchen, radial circuits for remainder of house. 👍🏻Just makes sense.

Rings for utility and kitchens are a must in my opinion. Fair power distribution across a circuit is an important factor to consider when designing.

@@jaydenplaysguitar3896 if only people would actually design rings with "fair power distribution across the circuit" trouble is it never happens, rings are always installed in the easiest, shortest route from socket one to the next rather than considering how much load might be on one leg, which is normally the dishwasher, washing machine, kettle, oven, microwave all next to each other on the same leg. SparkyNinja did a good video on balancing rings and loading a year back

That's the wrong way around surely... 6mm squared is 36, (as in 6 squared = 36), 6 square mm is 6 square mm

So are you saying there should be overcurrent protection on ovens, which John says there is no need for?

One of those infamous NEMA 10 connectors with the chassis connected to neutral. What could possibly go wrong? At least it's only 120V to ground...

@@johnburns4017 in the UK absolutely not. In the USA at the current time absolutely not. It was an anecdote vaguely related to the topic.

If your element goes that thermonuclear these days in either country something is going to trip before it gets to that point

@@TheEulerID indeed the very concept horrified me when I first made the move to the US

Here in Germany you're not allowed to pull more than 20A from a single phase (Schieflastverordnung, "asymmetric load act"). So our Cookers or hobs are usually supplied by 3x16A three-phase in Y configuration, so 3x230V. Cable is 5x2.5mm². We don't have isolator switches, just a cooker outlet (Herdanschlussdose) with screw terminals, from which a flex cable runs to the cooker. To isolate the appliance, you just flip the breakers. If you have an oven separately from the hob, it usually gets its own 16A breaker. Single phase installations get more and more rare, three-phase has pretty much been standard for the last 50 years. Even the smallest flats and apartments usually have three phase power. You can usually bridge the cooker's input to supply it with a single phase, but you're then limited to 20A. Although they're still some really old installations, where the cooker has a 25A or even 35A D-System fuse (slow-blow).

"Stove" is used in England for said item but is an old-fashioned term for such things - and tended to be more used with gas - hence 'gas stove'. The enamelled finish on such appliances being commonly referred to as 'stove enamel'. Here, a 'range' is a similar thing but on a significantly larger scale - 3,4 or more ovens and plenty of places for heating pans or boiling water. These were developed around a solid fuel fire (wood burning, coal or coke) and were likely known in America in its 'early' modern days - and not surprisingly, the name is still used for the smaller 4-burner 'cookers' that are common in England. One thing to bear in mind, if you compare photos of equivalent cooking devices between US & England, ours are always much more compact due to our more compact style of 'average' homes. While a US 4 hot plate cooker may well have space for pans between the hot plates, you will not find this on typical appliances in England - where in fact lage pans placed on adjacent hot plates may well have to be touching each other to centre them on the hot plates !

@@millomweb Similarly in Wales and probably Scotland and Northern Ireland too! 😉

@@Zenmelin I'm now using 'England' instead of Disunited Kingdom.

@@Zenmelin In North wales the word for cooker is 'Popty'.

I'd be interested too. Some manufacturers specify a 16A breaker. On a recent job I has two 3kW ovens that specified a 16A breaker. I ended up putting them on a 32A breaker, to a cooker isolator, to two 13A fused connection units to try to comply. Easier to whack them both in a cooker plate. If there was an accident like a fire that started on the cooker circuit, I wonder what the verdict would be.

Max demand less than mcb breaker less than current carry capacity of the cable.. simple rule. Otherwise you are not protecting the cable like you mentioned.

And a 2.5mm rating at 27 amps is for clipped direct method c. Most installs are ref method B or worse. With a 32 amp mcb your izs are...well...

Uk cables are sized on cross sectional area, not diameter. 8AWG is equivalent to about 8mm2 4mm2 as in the video is approximately 11AWG.

@@jwflame Thanks for the reply!! As if it is not confusing we use AWG, they also use diameter in mm , instead of mm2. Keep up the great, great work, JW !

Yes I don't even think there are any fittings designed to take 10mm. It's terrible stuff to work with.

Slap an RCD on everything, use metal clips occasionally, and do 30x more paperwork... seems to be the only major changes to me. (Car charging and other weird stuff excepted) (Oh and metal CU's, altho the regs don't actually SPECIFY metal, just non combustible. It could be argued that bakelite is not flammable, so a 1980s wylex board on a non flammable base would comply except for the RCD part) The old style wylex RCDs with the phenolic base and covers would be ideal for up front protection on TT supplies

It's all the same thing with ring mains - configured on the presumption that not all sockets will be supplying 13A all at the same time!

Oddly when ring mains (calling them that will anger JW! but it's how they were named when introduced) were first introduced... overloading in that manner was more likely (electric fires/heaters). These days the most likely issue is multiple stacked extension leads, officially bad practice but if they're all supporting 10w maximum... i don't see the issue,. other than the fact that the uninformed will be as likely to plug the fan heater into the end of that string rather than the other half of the double socket. Oddly as i type this I am facing that issue with a fan heater on the end of 2 extension cords lol.. it is still chilly at 4 am

TheChipmunk2008 - the biggest issue with one or more extension leads, is that it is possible to plug in two 2kW heaters. I have seen this done. Because both heaters had thermostats (they were both the same type) the fuse in the plug to the extension lead never blew, as each heater would cycle on and off. But if cheaper heaters without thermostats were used, the 13A plug and maybe the extension socket could overheat before the 13A fuse blew, and hence be a fire risk.

TheChipmunk2008 - when the ring system was introduced, it was rare to have many sockets in a room. One or two appeared to be typical. It’s unlikely that you would have more than one electric fire / electric heater in a room. And not many families heated every room with an electric heater. So I don’t think there was much chance that the 30A fuse would blow.

@@TheChipmunk2008 Nope. The document that was the outcome of the Electrical Installations Committee "Post War Building Study No. 11 - Electrical Installations" published by HMSO in 1944 refers to them as "ring final circuits". Quote: “There is no doubt that in modern domestic premises that are to be adequately provided with electric points, the cheapest and safest system is to use a ring final circuit.” Ring-main has always been a misnomer in domestic installations, it proper use being at the level pf the DNOs. www.abebooks.com/servlet/BookDetailsPL?bi=22877611357&searchurl=fe%3Don%26sortby%3D17%26tn%3Dpost%2Bwar%2Bbuilding%2Bstudies&cm_sp=snippet-_-srp1-_-title17

I've just downloaded a random installation sheet for a hotpoint 4-ring freestanding uk cooker and it says it must be provided with a 45A supply.

@@kevvywevvywoo To keep to guarantee, you will need to get a 45A mcb. If not available then apply the diversity factor.

I also use 2.5 for a single oven. 4.0 if it's got a microwave on the same circuit.

I only bother the spiders and slugs if they surface.

My halogen hob doesn't stay 'hard on' when set at maximum. I don't think any cooking element would be designed to do that. It's preferable to design it so that the element gets to maximum temperature quickly and then use a thermostat to prevent the inevitable overshoot which would lead to destruction of the appiance. If the appliance could only reach maximum temperature at the end of the exponential decay associated with the element's temperature rise, it would take perhaps an hour to reach 90% of maximum. You're better off doubling the power rating of the element and letting the thermostat intervene after a minute or so when maximum temperature is achieved.

@@westinthewest lol this isnt a David Savery video, talking about HARD-ONs

@@barrybritcher Agreed. We uphold higher standards of decorum on JW's channel.

@@westinthewest Bog standard electric element ring - 100% on all the time. Gets to full temperature in a minute or 2 without a pan on it - and presumably the increase of electrical resistance prevents it over heating - so the heating element is its own thermostat!

Really ? Shouldn't it be 2·5?

heck, anything higher than 8mm^2 (6mm^2 on the eastern world) generally shouldn't be used in the average home, unless it's running to a shed or other building.

10A plus 30% of the combined load - exactly the same as for a cooker. The fact they are in two separate pieces doesn't make any difference to the electrical load.

@@jwflame I see no reason not to connect built in ovens to a ring main rather than a dedicated 'cooking' supply. Seems that's the norm with combi microwaves/oven/grill.

@@millomweb I think it's for maintenance, so if you're working on the oven you don't have to turn off the ring or any other circuit.

Diversity SHOULD be understood by every sparkie. However ... In our LAST house, diversity at family gatherings - Easter, summer, and of course Christmas was ZERO (4/5 ring hob with halogen double ring, double oven)! It drove my wife (and me) NUTS as she would be part way through cooking and the 32A mcb would trip EVERY time without fail when she turned on the top oven to cook parsnips etc! NOW, it's a complete non issue as the double oven ONLY is on a 32A breaker, but the hob is on the kitchen ring ... it takes barely 1.5A! ... It has a "sensible" fuel for cooking ... GAS! I NEVER understood why anyone EVER thought it was a good idea to burn fuel (usually the exact same gas as delivered to your gas cooker!) to produce heat to produce steam to turn a turbine (MASSIVE losses), to generate electricity (MORE losses), transform the electricity (yet more losses x2 MINIMUM!) JUST so it can be delivered to a property to turn it back to heat! Insanity on a stick All the time, THROWING AWAY 60% of the original heat energy! ALSO, large modern, all electric 6 or even 7 way hobs on triple oven ranges are way more common these days and often need 2 x 32A breakers and 4mm² for each would be OK but only just. Induction hobs also consume a lot more but are more efficient generally, but still may need two feeds or a 40-45A breaker and suitable cabling. Personally, I'd rather see installations made using 6mm² simply to obviate the need for otherwise unnecessary "construction" work when someone decides they want to remodel their kitchen and switch to all electric from an old gas/electric. Worried about an extra few quid on a SINGLE run of 40 feet of 6mm² v 4mm²!!?? WHY? Who benefits? The consumer? Err NO! NEVER! Plan for the future, save the consumer a fortune on having to rip their place apart JUST to lay a NEW, replacement 6mm² costing just an extra £20 or so if done up front, or potentially thousands if done later!!??