HN user
London programmer.
Interesting idea, I suspect it isn't possible with the existing connector. You either need to increase the voltage or the current.
The new 240W spec is 5A and 50V. Assuming 5A is the thermal limit of the connector and that can't change, to get 1500W you'd need 300V, which is probably higher than the connector can support in terms of conductor spacing.
There's not a single smart plug on market that won't connect to cloud to control plug from anywhere
Look at Shelly devices, they are exactly what you are looking for (in no way affiliated)
Interesting point, but of course it’s not possible to create a platform with an average win rate of 80%.
Grounding isn't really about dispersing energy over an area, it's about creating a situation where faults can be detected and circuits automatically opened to prevent shocks or fires. It actually gets very involved to reason through the exact purpose of ground connections when you start considering all the different types and combinations of faults (indoors, outdoors, person in contact with true earth, person touching exposed metal pipe, etc etc).
Very often with contract law there is mostly no such thing as 'knowing a claim is not legally valid'. A lot of contract law is established by precedent, meaning in those cases nobody including the judge knew the enforceability of the issue before the judgement was written. Cases are also rarely identical examples of previous cases, meaning there can be an element of precedent setting even in cases that seem routine.
I suspect (IANAL) that in a sense, it already is, in that anybody testing this in court would deny the existence of any form of contract acceptance, and that would be the end of it.
And that heat ends up at the worst possible place, on the junction itself, meaning the device has to also work to remove it.
For an article about a specific scientific concept (the proportional land use for different types of generator), it’s surprising they actually got that concept wrong in all their examples:
“These can have a small land footprint of just 8m2 per MWh”
This is implies that the land is being consumed by the generator. I assume there is an implied “per year” or “per day” but it’s a little sloppy.
They look identical to me too, but I know that I can perceive RGB hues.
This has been true of OSX, especially since around 10.15. The performance degradation of the upgrade to 10.15 from 10.14 was so immediate and severe that I reverted it.
It only had itself to blame
And the atrocious disregard for performance over the last few years. My 2014 OSX 10.14 home Mac Mini is so much faster and more responsive than my 2021 OSX 12.4 work Mac mini (with no notable difference in features) it is difficult to conclude anything other than malice.
For some types of power supply, not having a proper ground can dangerous for reasons many people don’t realise. It’s not just about fault currents ‘flowing to ground’. Should just the supply neutral become disconnected, such as during high wind, then without a proper ground setup every metal item in your house that is grounded (such as microwave cases) can become live. It depends on how things are configured, but this type of lethal fault is a real possibility if neutral and ground are bonded at your house as they often are.
In the case where your power is derived from another property as you describe, in the UK we would normally call this a ‘TT’ power supply which you can google. It is absolutely essential (life and death) to have both a good grounding rod and an RCD at your end.
A others have said, get an electrician who understands the subtleties of outbuilding power supplies. If you cannot do that for whatever reason, I suggest first reading up extensively on the different kinds of earthing system, and finding out which one you effectively have.
Since you had no ground previously, it is likely that just live and neutral have been exported from your neighbours property (TT). You can probably check this by visual inspection, and it isn’t actually a problem provided you fix the grounding and protection at your end. To fix this grounding problem what happened? Did the electrician install a grounding rod? Did they happen to measure the impedance of it and write that somewhere? Do you have an RCD in your consumer unit (fuse box)?
Interesting observation, yes, power might restrict the deployment as much as running e.g. cat5 to a fixed camera install. A decent PTZ can easily see over that kind of range - some of this stuff can see for km in the distance:
In response to the comments of the form "just install PTZ cameras", I have done an installation like this for a modest-sized site, and it is extremely difficult and time consuming (+ expensive) to install enough cameras to cover the site if you want any chance of actually recognising a face or a numberplate. If all you want to know is: "blob detected at rear gate", it's of course a lot easier, but then you might as well use a PIR sensor.
The problem is mapping a 3D space, where a 'perp' can often face in any direction, onto a series of 2D planes. PTZ cameras only help if they are meticulously programmed to track movement or respond to motion events from other sources, or you have a skilled operator 24x7.
It's even harder if the system needs to work well at night, since it requires either IR or visible light illumination.
I don't know how well this drone+sensors setup would work, but can definitely imagine there is a subset of the market where this would be better than fixed cameras, perhaps a large property where there are multiple entrances and exits, and lots of potential targets. e.g. a farm, where there are long easily traversed boundaries between the property and neighbouring properties.
Agreed. As an existence proof, the optimising compiler for language X could realise that a for() loop that uses 95% of the actual runtime CPU has no side effects and can be removed. There may be some feature or property of language Y that makes that analysis impossible.
In the Java case, the JIT performs a runtime analysis. Without wanting to making any assertions about overall performance here, there exists a non-zero set of programs for which runtime optimisation is superior to static compiler analysis.
1440*2 different pre-rendered videos I assume.
I think the key conceptual thing that's difficult to grasp is the propellor's interaction with the wind.
Forgetting the speed of the car vs the wind for a moment, the propellor is arranged so it is trying to push air into the wind (i.e. it is propelling the craft). So, whatever force the wind might impart on a simple flat disc of similar radius to the prop, the force the prop actually experiences is higher than that because it is pushing against the wind.
For me, this realisation that the prop is pushing against the wind, increasing the overall force, unlocked understanding how this craft is possible.
Americans represent ~4% of the world's population. About 32% of Americans have graduated college. ALREADY I'm part of ~1% of the world's population [...].
FYI, other countries have effective college/university programmes too :)
Basically, in the EU, UK and Russia I can't even reconstruct your database piece by piece.
You are entitled to create a similar database based on your own efforts or research. So, you could walk the streets of London with an iPad to make your own KmlxStreetMap. You just can't directly copy or transfer rows from someone else's.
This seems like a good page: https://www.pinsentmasons.com/out-law/guides/database-rights...
What do they feel like for you? I’ve had a CO2 sensor in my office for a long time, and don’t think I can tell the difference between 500 and 1500ppm.
I personally don’t understand the claimed need for such high bandwidth for video calling and general business use.
My work laptop has forced software updates, so at the start of lockdown, to protect my home internet connection I hard capped it to 4Mbps in both directions at the switch. I’ve been having ~back-to-back Meet video calls all day for an entire year without exceeding this or having any problems.
I think the quality of the connection (consistency, upstream contention, jitter, packet loss) is probably far more important for most practical business applications (ie excluding HD Netflix, game downloads etc).
Another scummy website that hijacks the back button. I wish there were a way to block domains from the results I see on HN.
Both PCs and fan heaters are 100% efficient at producing heat.
In my view the audiophile £500+ Ethernet cables are more than borderline fraud.
Obligatory: https://xkcd.com/1150/
I have been gradually installing Shelly relays and dimmers in my place for some time, and they are excellent. They have a fully open and documented REST API, a simple but effective local web interface, and any Cloud connectivity is completely optional.
I have never had one fail (N=25). Since installation, I have never had one drop off the WiFi or require a physical visit for any reason at all (one is installed in my boiler and it takes an hour to get it apart, so I really appreciate this!). I honestly don’t think a single one of them has missed a single rest API call in the time they’ve been running.
When initially installing them, this can be done from a mobile next to the unit, at which point you join them to your WiFi.
I’m not in any way connected with Shelly, just a very impressed user of their stuff.
In practice a lot more since people don’t use their full connection 100% of the time.
An instantiation of me from a backup, however accurate, would be no use to my sense of having survived as I would have ceased to exist and not even be aware of the copy.
FYI, this query took 81 seconds:
select count(*) from trips where fare_amount > 0
Presumably this is Hacker News load?