-rick-

I think they are just answering a different question and expect someone who is working with electrics to know what they are looking for. They are just talked about current carrying capacity of the cable. Up to you to work out how much current your devices will need. Yep so some derating required. 13A socket is not rated for 13A continuously. But kettles are only on for a few minutes before they boil. I would guess a lot less than that. My oven seems to warm up pretty fast and it's not a fixed install (got a 13A plug on the back) so isn't the most powerful. One of these threads triggered me to look up the ratings of fixed install ovens and for single ovens they are all saying they need 16A breakers. So if they are installed on a dedicated circuit with a 16A breaker there is no diversity applied. (Electrician will still do calcs for sizing upstream components). Sounds about right (caveated that insulation/distance derating might drive requirements higher), though my own thought is to always use 4mm as that allows the potential to switch from a single to double in future without rerunning wires. (4mm might not be enough for a double if big derating factors are required). I missed that your ovens are fixed installation in the other thread. If they don't come with a 13A plug (and are therefore fused) they need a dedicated circuit (as the dedicated circuit provides the fuse).

Do you not have separate controls for each ring on a hob? If you only have a single point of utilisation, all the rings turn on when you turn one on? Modern induction hobs usually have ratings for the individual rings and even break out groups of rings to different wiring terminals (to allow you to split the load over multiple phases).

We are such delicate flowers these days! Don't get me wrong, if I get to build I'm getting the cisterns with built in extract to remove the smells at source but to have this as a notable selling point for a £5-10k installed item makes me laugh.

Forgot to say, this does seem like it would be a bad thing if it applied to balcony solar type setups. If people have to pay engineering fees to plug in a device to their wall outlet whats the point in the changes on balcony solar? But the wording suggests it applies to only some situations which I would guess 800W of balcony solar is not going to be one.

Good question Joth. Either way, I don't find this idea bad. Seems reasonable to me. If you are spending £5000+ on solar (and given currently pricing are going to get payback for that very quickly) why should the rest of us sponsor the connection? If solar was a money loser for people and just done for environmental reasons then sponsorship makes some sense but given solar is so profitable that HMRC are going around reminding people profits from home solar generation is reportable income then further subsidy to higher income people seems wrong. Not against providing incentives for lower income people to get solar. That feels like a different situation.

Depends on your device. Expensive ones can do some form of variable power, though I would call PWM a smart form. The dumb control is bang-bang control (https://en.wikipedia.org/wiki/Bang–bang_control) But again this is irrelevant to the discussion. Even the bang bang control leads to the average current draw for the hob being much lower than the max draw. Again, if there are short periods where everything aligns and every hob is on simultaneously for some seconds that's accounted for.

That's the point. Even if every ring is 'on' most of them won't be drawing much power. Most will be drawing a fraction of their rating to maintain the temperature. The only time a ring will draw maximum power for more than a handful of seconds is after you first switched it on and say you have a pan of water you want to bring to the boil. Then that ring will be on for like 2-3mins continuously. It is exceedingly unlikely that your wife (or anyone) goes into the kitchen, gets out six pans and puts them all on the hob at the same time and sets them all to max. Even in that case, the rating on a circuit is designed for cable protection, ie, a 32A circuit can sustain a 32A draw continuously over many hours on the hottest day of the year without melting/starting a fire/etc. The cable (and the breaker) can sustain much higher currents for short periods of time and that's what these diversity calculations take into account. They allow for a short period of very high usage (much higher than rating) so long as the average over time is below the rating by enough.

Don't think that's right. There are multiple elements in cookers/hobs. Not all are on at the same time for long time periods. Video I posted in another thread showed regs saying a 32A (7kw continuous) feed was sufficient for a cooker rated up to 18kw due to diversity calcs. (I'm not an electrician so don't rely on what I say)

I'm quite happy with my decision to spend zero time trying to imagine whats going on in @Pocsters head!

Of course you were! (though I didn't see the buy of the Mac as part of that, just assumed you were impatient/had money to burn). Glastonbury tickets all over again 😛 Amen. Though before you spend money I assume you have a prototype running (at lower model size) on existing hardware?

@jack?

Sorry, thought you'd be too busy chatting up your new llm girlfriend to notice 😏

This is not the point you are making but what's going on with Iran is massively constraining the supply of Helium. Qatar is the main producer. US Labs have been told to expect a 50% reduction in supply. This affects MRI's, chip fab and a load of other things. Everything is going to get very difficult very soon. If the global economy takes a real dive, one silver lining is that when the Iran crisis is over the AI companies might not have such deep pockets (or in some cases still exist) and so memory might become more available again. Then again, nobody else will have money either. 🥴

Well this escalated. Not trying to win an argument or even have an argument. When a response to a post of mine doesn't seem to engage on the points in my post I wonder if I didn't explain it well enough so try again. I think you understand my points now so not worth going further. The one thing I will point out is that the shortages are all on older gen stuff. M4 mac minis, M3 mac studios. Products expected to have announcements of replacements in the next 2 months. It's a well documented Apple tactic to sell down inventory/put long lead times on products near this point (happens with iPhone, laptops, etc). It doesn't always happen because in general Apple has bigger surplus but if things are running low they don't bother to build more.

Pretty much everyone who lives in a city knows someone who has been affected by cladding issues related to Grenfell. A lot of those are EPS EWI related. So even if mortgages don't mind there are a pool of buyers who may be put off by EPS EWI. Mineral wool EWI doesn't have the same problem but is a lot more expensive and frankly I doubt many buyers who are nervous about 'cladding' are going to worry about the distinction. * Yes I know most buyers don't even know enough to think that deeply about what they are buying but even a subset of city dwellers moving out of the city is not a pool of people you want to put off IMO.

Totally agree with you that the high memory skus are not available. Just suggesting that in this case it is likely nothing to do with the memory shortage, more that Apple only ordered a certain amount of M3 Ultras with high memory and they have basically sold out and the M5 Ultra is so close to launch they don't want to order more M3s. It's true that fab capacity is limited these days due to the AI boom so if Apple is choosing where to allocate resources it will choose the M5. Very different: This custom integration means custom manufacturing with long lead times. Apple will order these chips like a year before they plan to use them and will order in very large batches. Yes there is a crunch at the factories that means that if Apple wants to order more it has to fight others (and pay more) but fundamentally, if Apple ordered more M3 Ultras now it would be many months before they arrive so from their POV why not just wait for the M5 Ultras that they ordered a long time ago. Yes Apple sold out of the high memory skus, but my argument is they have sold more than expected, not because they can't get memory. I expect the M5 Ultra will launch in June with a delivery slot that is a little earlier than the lead time currently mentioned on M3 Ultra orders. They will then offer people who ordered the M3 the option of the M5 (possibly with a different price). Those who accept will get the M5, those who don't will get whatever's left of Apples stockpile, not that many will say no to the M5. (Just because they have 'sold out' doesn't mean they don't have any on the shelf).

Source please? I've seen the 9to5mac story which doesn't really say anything. Remember Mac Studio uses different RAM from any typical AI server (or desktop PC). Completely different silicon die. Apple is likely the only company ordering high capacity ICs of the type used in the Mac Studio. I think in this specific case they have sold out of their pre-manufacturered supply of these skus and have redirected manufacture to the m5 rather than the RAM shortage overall. Assuming they are going to announce a M5 Ultra at WWDC, pushing the orders out 5 months gives them room to announce the M5 Ultra (with delivery in August/Sept) and then go to all the people who ordered the M3 Ultra 'Oh, we have a new model now, do you want that instead?'

News over the last few days has been that OpenAI (and others) have been pulling back their Ram orders (they signed letters of intent not actual orders). They always ordered too much to be able to use (can't build datacentres fast enough). Apple signs very long term contracts for memory and has been able to avoid a lot of problems hitting others. Apples prices may go up but I doubt they will experience a significant shortage (no manufacturer wants to piss off one of the largest single buyers out there who is willing to sign longer term deals). All the memory manufacturers have been through plenty of boom-bust cycles and are trying hard to avoid the same this time (and thus aren't building much new capacity).

Not entirely sure this particular thing is ram delays. Huge amount of media coverage of using high ram m3 ultras for AI recently and I'm sure there were a flood of people buying them. With Apples soldered on RAM it's not trivial to make more systems when you get a sudden surge (even if you have the chips), especially if the production line is currently focussed on churning out m5 ultras ready for launch.

Watching a set of keys attached to a chunky padlock crash down a 6 storey smoke vent (metal grate floors) was a not dissimilar experience. Not worried about them getting damaged but rather doing damage on the way down and getting stuck somewhere inaccessible. Somehow it made it all the way down to the basement through the relatively small grating despite the lock + keys being a very chunky handful.

Not sure you got what I was trying to say? Signalling open or closed would be the default assumption but I'd guess with careful placement of the the sensor you could instead have secure / not-secure. ie. to tell the difference between a window that is closed but with the handle in a position where the window could be pushed open from outside to one where the handle has latched the window securely closed (or in trickle position if it exists).

Been a while since I watched it and not 100% sure this is the video I'm thinking of but I think the below will explain this if you don't mind the presentation. From about 6:28 in if you want to skip the bit on cable size.

Firstly, I'm not an electrician, but from what I know electrians always apply diversity so don't calculate based on 'everything on'. Secondly, I wouldn't expect Microwave or warming drawer to be on the Oven circuit. The Hob is the main thing that needs a dedicated connection. Wouldn't be surprised if everything else is intended to go on the ring main, All these devices peak loads are way way higher than their continuous.

This flat started as brand new as well. Everything ages. I'm not sure that I'd ever agree that it's worth buying a brand new oven because the timer stopped working. The replacement part was £250 (may as well buy a new oven). In the end I fixed it for <50p and some solder but I'm not most people. Specifically about the hob I don't see any immediate need, my point was you don't know what you don't know. Having the ability to isolate has been useful to me in ways I wouldn't have predicted. That's all I'm saying. I agree this is not an area for smart stuff though. (There are some clever uses of monitoring current draw of appliances in a smart house but switching on/off no).

My flat came with a multigrid style switch on the wall with isolators for everything in the kitchen. I'm really surprised at how much I've used it. This probably isn't typical but for me it's come in handy a lot, especially my kitchen is coming to end of life and things are breaking. (I'm avoiding replacing things piecemeal and would rather either do it all at once or sell the place with the kitchen as 'in need of refurbishment'). Lot's of things break in ways that don't stop them working but are annoying to leave switched on. Timer module in oven is best example. Oven worked fine except timer, but with oven powered the timer made a constant buzzing. In this case I ended up fixing it when I replaced the oven fan but in the meantime it was very convenient to have an easily accessible switch.