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What's that touchscreen in my room?

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Re: What's that touchscreen in my room?

#461

Post by mrd3v0 »

fouc wrote: post #427
miellaby wrote: post #136

I like how the author is surprised by the technological aberration that form Linux powered home appliances. A node server to power and publish over wifi a web site, an API, a web socket, while the site is being displayed by a outdated webview engine within an heavily constrained terminal which cant be reused for anything else. That's... the norm. All this is very common. And yet displaying a couple of digits and a ba…

> A node server to power and publish over wifi a web site, an API, a web socket, while the site is being displayed by a outdated webview engine within an heavily constrained terminal which cant be reused for anything else. That's... the norm. I really wonder why this happens. Seems penny wise & pound foolish. Perhaps they failed to hire the right developer for the right abstraction level, and ended up with "web devel…

Money. That's almost always the reason for "why would they do that?"

It's much cheaper and more sustainable for the wealthy and powerful to train individuals on very high level technologies then reuse their skills in every way they can, regardless of how feasible, the economic and ecological footprint, or any concern outside of making profit.

Electron is not some comic book villain. JavaScript is not horrible and can be the optimal choice for many software applications.

But these technologies and tools are easy to teach to many workers who may or may not: understand the computational architecture to come up with better economic efficiencies, have interest in applying their skills to properly solve a problem rather than put food on the table, and so on.

The higher level the skill is, the less interest and deep systemic understanding needed for the job: many new jobs created.

Re: What's that touchscreen in my room?

#462

Post by rokweom »

owenversteeg wrote: post #440
rokweom wrote: post #278

Earlier quoted context omitted.

In general, people have the wrong idea about how fuses work. They're not supposed to blow at their rated current, they're supposed to withstand it indefinitely , and only blow at much higher currents. Look up any datasheet from a well established manufacturer and see for yourself (like this one from littelfuse: https://littelfuse.com/products/fuses/cartridge-fuses/5x20mm... )

Indeed. There is a slight temperature dependent de-rating, but in general that is correct. To add, Littelfuse is in fact the inventor of the standard automotive blade fuses - they know their fuses if anyone does. I archived a datasheet of some of their blade fuses here [0] - you can see that a 1-amp fuse will run at 1A indefinitely, 2A for 300ms, 3A ~100ms, 4A ~60ms, 5A ~40ms etc. The same datasheet will tell you the…

Just be careful with that, measuring mains is a bad idea with most oscilloscopes. The ground pin is usually connected to mains earth, so if you're not careful, you might create a short and blow up your scope. If you have one of these battery powered ones, it'll be fine, but the mains powedered ones are usually a no-no.

Re: What's that touchscreen in my room?

#463

Post by Symbiote »

philwelch wrote: post #426
lazide wrote: post #412

Earlier quoted context omitted.

The odds a random US plug will be 240v is essentially zero, unless you’re standing next to an electric range/stove/dryer. And those plugs typically have one outlet and it’s already in use. Unless the prior owner was a welder anyway. Then you might have a few in the garage. Either way, not convenient for kettles.

Maybe I should make the obvious reason more explicit. If you have something designed to operate on 120V and plug it into a 240V outlet, there will be safety issues. It might even catch on fire. So the two voltages have to use different outlet and plug shapes for safety reasons. An outlet is not “randomly” going to be one voltage or the other because that would be a terrible idea. And yes, the 240V outlets are set up…

I think the main speed increase of American machines compared to European ones is due to much higher water consumption.

A modern European washing machine uses 30-50 litres per wash, vs 75-100 for a modern American one.

That's also halved the time required to heat the necessary water, so another reason a hot water connection might not be so useful

Re: What's that touchscreen in my room?

#464

Post by IshKebab »

owenversteeg wrote: post #440
rokweom wrote: post #278

Earlier quoted context omitted.

In general, people have the wrong idea about how fuses work. They're not supposed to blow at their rated current, they're supposed to withstand it indefinitely , and only blow at much higher currents. Look up any datasheet from a well established manufacturer and see for yourself (like this one from littelfuse: https://littelfuse.com/products/fuses/cartridge-fuses/5x20mm... )

Indeed. There is a slight temperature dependent de-rating, but in general that is correct. To add, Littelfuse is in fact the inventor of the standard automotive blade fuses - they know their fuses if anyone does. I archived a datasheet of some of their blade fuses here [0] - you can see that a 1-amp fuse will run at 1A indefinitely, 2A for 300ms, 3A ~100ms, 4A ~60ms, 5A ~40ms etc. The same datasheet will tell you the…

So you agree that a 2A fuse shouldn't allow 8A to pass for several minutes?

Re: What's that touchscreen in my room?

#465

Post by Symbiote »

lazide wrote: post #430
philwelch wrote: post #426

Earlier quoted context omitted.

Maybe I should make the obvious reason more explicit. If you have something designed to operate on 120V and plug it into a 240V outlet, there will be safety issues. It might even catch on fire. So the two voltages have to use different outlet and plug shapes for safety reasons. An outlet is not “randomly” going to be one voltage or the other because that would be a terrible idea. And yes, the 240V outlets are set up…

Uh, you might want to reconsider who you’re talking to. I’ve run 40 amp 240v split phase and 3 phase in North America (permitted) for personal projects. I’m well aware. No one installs L30R/L6-30R receptacles in the US for ‘normal’ (as in used by a human for random stuff) use as standard practice, because yes - most of the time no one needs it. Maximum power for a normal 120/20 amp branch circuit is 2.4kw, and that’s…

"Normal" high power portable devices in Europe are 2-3kW electric heaters (generally an expensive way to heat a house, but OK if you're heating a single room) and older and less efficient vacuum cleaners (2kW).

Maybe also a very high spec gaming PC, which here could run (monitors and all) from a single outlet. Would tripping the breaker have been a concern at a 2000s LAN party in the USA? I have no idea.

In some countries it's common to have a 400V (3 phase) socket in the garage. Excellent for car charging, but that is also OK from 230V. That is probably by far the biggest current benefit of 230V everywhere. Charge the car at a decent speed at that holiday cottage in the mountains.

Re: What's that touchscreen in my room?

#466

Post by ahrjay »

jonathanlydall wrote: post #128

A few years ago I came to the realisation that if you want people to be more environmentally conscious or economical in terms of utility consumption, (electricity, water, gas, etc), they need far better data than a single figure per month. You want to be able to see usage to a resolution of at most 5 minutes. That way people can spot things like “having my electric heater on for those couple of hours used more electr…

In my home state of Victoria Australia the government had a program to give out these powerpal[1] units for free that could measure your usage in realtime using the flashing led on our smart meters, we also require all energy grid operators (the people who own the poles and wires) to have an energy portal where users can get near realtime data to the nearest 30mins, soon to be 5 with some new legislation.

The former most people have no idea about but the powerpal has been a smashing success for consumers to understand what is using energy.

[1] https://www.powerpal.net/

Re: What's that touchscreen in my room?

#467

Post by Symbiote »

avgcorrection wrote: post #401
stdbrouw wrote: post #222

Earlier quoted context omitted.

Your experience also points to the limits of monitoring and subsequent behavioral change, though. I mean, yeah, it might prompt you to start your washing machine a bit earlier or a bit later to align with high production by your solar panels... but how much consumption can you really move around like that, and how many energy hogs can you just decide to not use? If you notice high energy use while cooking, are you go…

> but how much consumption can you really move around like that, and how many energy hogs can you just decide to not use? If you notice high energy use while cooking, are you going to start eating more salads instead? There’s been some interest in this locally due to energy regulation moving to a more punishing system for peak usage. Also high electricity prices. And the topic came up that people would be encouraged…

Maybe it's because Britain introduced cheap electricity overnight in the 1970s (before I was born), but I've never thought of using the washing machine overnight as unsafe. The dishwasher too.

Trading electricity between Europe gives us lower prices overall, and a more stable and efficient grid.

Re: What's that touchscreen in my room?

#468

Post by Symbiote »

gambiting wrote: post #291
robinsonb5 wrote: post #285

Earlier quoted context omitted.

For comparison, I live alone in a mid-terraced 2-bedroom house in the UK, heated with gas - and I'm currently there most of the time. My monthly electricity usage is about 180kWh a month. I'm guessing a big chunk of the 60kWh I'm using over your baseline is the kettle! :D

Uhm. We have a 3 bed semi detached house, my consumption for November was 1267kWh of electricity. In October it was 1148kWh. And I also heat with gas(well we have a minisplit upstairs that we sometimes use for heat, but it uses like 5kWh/day max) No idea how you use so little lol.

That's very high. Has a neighbour plugged their car into your outside socket? Underfloor electric heating in the bathroom? Someone using that minisplit more than you think?

Average monthly use a house like that in Britain is 225kWh.

https://www.ofgem.gov.uk/information-consumers/energy-advice...

Re: What's that touchscreen in my room?

#469

Post by TeMPOraL »

fouc wrote: post #425
masklinn wrote: post #338

Earlier quoted context omitted.

> I always wondered why we cannot find hot filled appliances in the old continent. You can find them but they'll be in the semi-professional space and above (relatively expensive high-duty). They're very rare in the consumer space because - it requires running more hot water lines / extensions, historically houses are built with lots of cold water lines but hot water lines only where required - for their heating requ…

for laundry - cold/warm setting + cold water detergent is popular these days, further reducing the heating requirement.

Oh yes, what's up with that anyway? I recently noticed laundry detergent companies making some magic "wash in 20 degrees Celsius" product, and heavily advertising it on the grounds of energy savings. I wonder how that works. I'm not sure my washing machine can even go as low as 20 degrees.

Re: What's that touchscreen in my room?

#470

Post by Symbiote »

madaxe_again wrote: post #153
kelnos wrote: post #53

> There were two strings printed with labels “SSID” and “Pwd”. I froze in horror. They wouldn’t dare. It is literally 3 meter distance. These are embedded devices, they do not need this complexity… Not surprising at all. I would expect that a lot of these are bought as retrofits, and not as a part of new construction. Running wires through existing walls can be annoying, and they don't want to put that barrier to sal…

>> To be honest, the whole thing was a bit scary, since I was very close to the mains I laughed at this. Changing a fuse is… a bit scary? They literally teach this in elementary school in the U.K. - or they did. As you say, no need to fretfully check the fuse - either it blows or it doesn’t, and you’ll know when it does. At least he didn’t find the receptacle holding a dead fuse, carefully wrapped in the ceremonial a…

Secondary school, but it's still in the revision guide so I assume they still teach it.

https://www.bbc.co.uk/bitesize/guides/z6r37nb/revision/6

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