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What's that touchscreen in my room?

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Re: What's that touchscreen in my room?

#161

Post by outofmyshed »

zarzavat wrote: post #89
tjohns wrote: post #77

Earlier quoted context omitted.

British household electrical systems are normally built as one large ring circuit, originally in order to save copper after WW2. This means you don't have breakers for each branch circuit (there are no branch circuits), just the single mains breaker for the house. This single breaker is too large to trip from a short from occuring in the smaller wires inside an appliance. So each plug (or hardwired device) needs it's…

To add: Many pre-90s buildings don’t even have circuit breakers, they have fuse boxes with fuse wire (different fuse to the one being talked about). Literally just a piece of wire that burns out at a certain current and breaks the connection. You “reset” it by putting a new piece of wire in. The second fuse at the plug allows using a narrower gauge of wire in the device’s cord. Let’s say you have a lamp with a 3A fus…

My last place had a 1970s Wylex board, which at least had plug-in MCB modules that replaced the fuse wire holders and can be reset. However given you can still buy fuse wire in DIY stores there still must be installations out there that need it. Shudder.

Re: What's that touchscreen in my room?

#162

Post by ako »

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…

Depending on your water meter this device may be useful: https://www.homewizard.com/watermeter/

Re: What's that touchscreen in my room?

#163

Post by a2800276 »

astrange wrote: post #78
Something1234 wrote: post #42

Earlier quoted context omitted.

I want to know more. History of java is just insanely weird.

SIM cards and secure elements (contactless credit cards) both use this, or did at one point.

SIM cards and secure elements still use this, but it's arguably less Java than Javascript. Except that the trademark and tech (JavaCard) was owned by Sun, now Oracle. It's the basis of the claim, that gazillion devices run Java.

JavaCard is a massively trimmed down version which is more a dumbed down C (with no standardization, little documentation and no third-party tool support) which is essentially Java reduced to basic arithmetic operator, an arguably saner, much trimmed down standard library focusing on cryptography and most importantly no GC.

Re: What's that touchscreen in my room?

#164

Post by Jedd »

8n4vidtmkvmk wrote: post #157
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…

Something in my apartment is consuming a ton of power and I don't know what. I would love a graph with a resolution better than a day.

Do you have a conventional HWS? These are notoriously power-hungry, often poorly maintained and calibrated, and hard to monitor.

You can buy a power meter plug - that sits between appliance and socket - and work your way around almost all your appliances apart from, typically, oven, air conditioner(s), and hot water systems. For those you're going to need to experiment by turning as many things off as you can, to establish a baseline, and review your switch meter periodically for short (several minute) intervals, with and without the larger appliances turned on.

(You can get induction coil systems to report usage of these larger appliances, but they're typically onerously priced.)

Re: What's that touchscreen in my room?

#165

Post by pmontra »

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…

Yeah, the author makes this pun

> C in IoT stands for “cost-effective” I guess

but it's actually C for cableless.

Re: What's that touchscreen in my room?

#166

Post by leoedin »

65a wrote: post #132
metadat wrote: post #63

> 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... Responding with disbelief seems a little over the top. It isn't typically easy to run wires in pre-built spaces. Sounds like a resilient design to me.

Not resiliant, because in the 10-20 year lifespan of a home electrical panel, at least one critical vulnerability is going to allow complete remote pwnage of that device. It's stupid IOT garbage that belongs in ewaste, especially with a trivial remote code execution mechanism.

There's not really much those devices can do - they're just metering, and don't have an active internet connection.

WiFi isn't a bad choice of communications protocol.

Re: What's that touchscreen in my room?

#167

Post by petepete »

On a related note, I had a new boiler installed last year with Vaillant's smart controls. There's a little puck shaped 'control unit' with WiFi/radio which allows the app to talk to it, and it to talk to the thermostat.

Like most people in the UK, the boiler's in the garage. A brick rectangle separate from the house. Did Vaillant include an ethernet port? You bet they didn't. The support team suggested I installed WiFi in my garage, which definitely wasn't going to happen.

I had to get the installer back and he ran the cable through the wall so it's now inside and working fine - but how did this ever make it to market? No wonder the reviews are all terrible.

Re: What's that touchscreen in my room?

#168

Post by bradley13 »

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…

Being able to see your usage is helpful - at least, for those of us interested.

For example, I was surprised to see how much our electronics (stereo, amplifier, TV, etc.) in the living room use, even when off (some devices are older, with high standby currents). It motivated me to put everything on a timer that only turns power own in the evenings, since that's the only time they get used.

It's a small thing, but small things add up.

Re: What's that touchscreen in my room?

#169

Post by leoedin »

azalemeth wrote: post #38

A fun read! I feel compelled to say that all British (type G plugs) _have_ to be fused as the ring main has a maximum current of (typically) 30A yet the plug and socket maximum is 13A. So every appliance plug is fused, and the consumer unit has an RCD on most accessible circuits in addition to a circuit breaker. Some plugs don't make the fuse obvious, but the traditional values are 1A, 3A, 5A, 7A, 10A and 13A (iirc -…

Ring circuits may have made sense in the past, but they really don't any more. It's basically impossible to test a ring circuit in place - you have to break the connection somewhere to ensure the ring is complete. That's a huge downside. They were conceived at a time when circuit breakers were expensive and wire was in short supply - neither is true now, yet people are still installing them.

Re: What's that touchscreen in my room?

#170

Post by eastbound »

fulladder wrote: post #119
xerox13ster wrote: post #98

Earlier quoted context omitted.

> A 3A fuse would burn out in a fraction of a second if you tried to do that. he bought it on Amazon. He has every reason to be worried that it won't burn out. Louis Rossman did a video[0] where he put 8 amps through a 2 amp fuse and left the room for quite a long time, I think it was several minutes with 8a going through a 2a fuse. [0]: https://www.youtube.com/watch?v=B90_SNNbcoU

That is very disturbing. Does Amazon reimburse you when your house burns down?

Seriously, I think they would refund the fuse since you are not satisfied.

I think the only way for Amazon to stop organizing countraband would be if dozens of people die in each country and it makes a big media mess and public prosecutors finally rule that Amazon is responsible for mingling and smuggling the products in-country.

Which will impact all marketplaces, requiring Craigslist/Leboncoin/Gumtree to asses the liability of the sellers on the marketplace.

Which could be a good thing.

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