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Remember a few years back when there was the story about the little girl who did an "Alexa, order me a dollhouse" on the news and people watching the show had t

Remember a few years back when there was the story about the little girl who did an "Alexa, order me a dollhouse" on the news and people watching the show had their Alexas pick up on it and order dollhouses during the broadcast? Wait until there's a widely watched Netflix show where someone says "Delete C:\Windows".

foobarian 2y ago
format c: /autotest
throwup238 2y ago
My wake word is "Computer" like in Star Trek, so I'm really worried I'll be rewatching an old episode and it'll kill the electrical grid when someone says "Computer, reverse the polarity." (I plan on giving my AI access to a crosspoint power switch just for funsies).
- Rygian 2y ago
  Nah, you'll just get live wire where neutral wire is expected.
  - Popeyes 2y ago
    So they will get a Riker instead of Data?
  - moffkalast 2y ago
    You know I've been meaning to ask somebody, people always make a fuss about which is which but like.. schuko and europlug and a few others are omnidirectional and aren't even labelled so chances are stuff is always plugged in wrong and it all works fine. I guess it's all rectified anyway so it doesn't matter?
    - aaronmdjones 2y ago
      It does matter in some cases. For example, in Edison screw desk lamps, the tip is supposed to be connected to line, with the outer ring connected to neutral. If this is reversed, there is a risk you can shock yourself screwing or unscrewing a bulb while the lamp is turned on, because now line is on the outside, much closer to your fingers. Worse, the light switch would now be switching neutral, so even turning the lamp off won't stop this. EDIT: Demonstration: https://www.youtube.com/watch?v=_Q5wYV3flKI https://www.youtube.com/watch?v=_Q5wYV3flKI
      - moffkalast 2y ago
        I mean I'm sure there are lots of cases where it's a problem, also AC motors should run backwards and the neutral will be contaminated, right? What I'm wondering more about is how it's compensated for (some kind of AC rectifier in the plug?) when symmetrical plugs will cause this error in 50% of cases. Like were the highly regarded people writing the standards just like "fuck it, if he dies he dies"?
        aaronmdjones 2y ago
        Most things will operate just fine with line/neutral reversal. AC motors will not run backwards; they use a phase shift capacitor [1] to ensure that they always start turning in the same direction regardless of where line is (relative to neutral) when the motor is instantaneously connected to a source of AC power. As you say, most things run on DC, and rectifying AC to DC doesn't care about line/neutral reversal. It does create some safety issues in certain applications as I described above. It can cause some things to misbehave. For example, in home energy monitoring, where you clip one or more current transformers around a circuit's line conductor(s) to measure the current consumption of that circuit and connect an AC-AC transformer (to reduce it to a lower voltage, to make it suitable for export on an extra-low-voltage finger-accessible connector like a barrel plug, and so that it can be measured by an analog-to-digital converter) to the unit, so that the unit can measure voltage (and thus work out power) [2], then if line/neutral is reversed, its observation of what it thinks is line will be at the wrong point (relative to its observation of neutral) when computing the power being transferred. This will result in the device telling you that the circuit is exporting power (when it is actually importing), or vice versa. It all depends upon the application. In most instances, line/neutral reversal is fine; and indeed with non-polarised plugs, unavoidable. However it should be avoided if possible. [1] https://en.wikipedia.org/wiki/Motor_capacitor https://en.wikipedia.org/wiki/Motor_capacitor [2] https://docs.openenergymonitor.org/emontx3/install.html https://docs.openenergymonitor.org/emontx3/install.html
gdhkgdhkvff 2y ago
Thanks a lot. I’m browsing this with my screen reader. …ok not really but that would be funny.

foobarian 2y ago

format c: /autotest

throwup238 2y ago

My wake word is "Computer" like in Star Trek, so I'm really worried I'll be rewatching an old episode and it'll kill the electrical grid when someone says "Computer, reverse the polarity." (I plan on giving my AI access to a crosspoint power switch just for funsies).

Rygian 2y ago
Nah, you'll just get live wire where neutral wire is expected.
- Popeyes 2y ago
  So they will get a Riker instead of Data?
- moffkalast 2y ago
  You know I've been meaning to ask somebody, people always make a fuss about which is which but like.. schuko and europlug and a few others are omnidirectional and aren't even labelled so chances are stuff is always plugged in wrong and it all works fine. I guess it's all rectified anyway so it doesn't matter?
  - aaronmdjones 2y ago
    It does matter in some cases. For example, in Edison screw desk lamps, the tip is supposed to be connected to line, with the outer ring connected to neutral. If this is reversed, there is a risk you can shock yourself screwing or unscrewing a bulb while the lamp is turned on, because now line is on the outside, much closer to your fingers. Worse, the light switch would now be switching neutral, so even turning the lamp off won't stop this. EDIT: Demonstration: https://www.youtube.com/watch?v=_Q5wYV3flKI https://www.youtube.com/watch?v=_Q5wYV3flKI
    - moffkalast 2y ago
      I mean I'm sure there are lots of cases where it's a problem, also AC motors should run backwards and the neutral will be contaminated, right? What I'm wondering more about is how it's compensated for (some kind of AC rectifier in the plug?) when symmetrical plugs will cause this error in 50% of cases. Like were the highly regarded people writing the standards just like "fuck it, if he dies he dies"?
      - aaronmdjones 2y ago
        Most things will operate just fine with line/neutral reversal. AC motors will not run backwards; they use a phase shift capacitor [1] to ensure that they always start turning in the same direction regardless of where line is (relative to neutral) when the motor is instantaneously connected to a source of AC power. As you say, most things run on DC, and rectifying AC to DC doesn't care about line/neutral reversal. It does create some safety issues in certain applications as I described above. It can cause some things to misbehave. For example, in home energy monitoring, where you clip one or more current transformers around a circuit's line conductor(s) to measure the current consumption of that circuit and connect an AC-AC transformer (to reduce it to a lower voltage, to make it suitable for export on an extra-low-voltage finger-accessible connector like a barrel plug, and so that it can be measured by an analog-to-digital converter) to the unit, so that the unit can measure voltage (and thus work out power) [2], then if line/neutral is reversed, its observation of what it thinks is line will be at the wrong point (relative to its observation of neutral) when computing the power being transferred. This will result in the device telling you that the circuit is exporting power (when it is actually importing), or vice versa. It all depends upon the application. In most instances, line/neutral reversal is fine; and indeed with non-polarised plugs, unavoidable. However it should be avoided if possible. [1] https://en.wikipedia.org/wiki/Motor_capacitor https://en.wikipedia.org/wiki/Motor_capacitor [2] https://docs.openenergymonitor.org/emontx3/install.html https://docs.openenergymonitor.org/emontx3/install.html

gdhkgdhkvff 2y ago

Thanks a lot. I’m browsing this with my screen reader. …ok not really but that would be funny.