this post was submitted on 24 Aug 2024
954 points (99.2% liked)

Lemmy Shitpost

26917 readers
2974 users here now

Welcome to Lemmy Shitpost. Here you can shitpost to your hearts content.

Anything and everything goes. Memes, Jokes, Vents and Banter. Though we still have to comply with lemmy.world instance rules. So behave!


Rules:

1. Be Respectful


Refrain from using harmful language pertaining to a protected characteristic: e.g. race, gender, sexuality, disability or religion.

Refrain from being argumentative when responding or commenting to posts/replies. Personal attacks are not welcome here.

...


2. No Illegal Content


Content that violates the law. Any post/comment found to be in breach of common law will be removed and given to the authorities if required.

That means:

-No promoting violence/threats against any individuals

-No CSA content or Revenge Porn

-No sharing private/personal information (Doxxing)

...


3. No Spam


Posting the same post, no matter the intent is against the rules.

-If you have posted content, please refrain from re-posting said content within this community.

-Do not spam posts with intent to harass, annoy, bully, advertise, scam or harm this community.

-No posting Scams/Advertisements/Phishing Links/IP Grabbers

-No Bots, Bots will be banned from the community.

...


4. No Porn/ExplicitContent


-Do not post explicit content. Lemmy.World is not the instance for NSFW content.

-Do not post Gore or Shock Content.

...


5. No Enciting Harassment,Brigading, Doxxing or Witch Hunts


-Do not Brigade other Communities

-No calls to action against other communities/users within Lemmy or outside of Lemmy.

-No Witch Hunts against users/communities.

-No content that harasses members within or outside of the community.

...


6. NSFW should be behind NSFW tags.


-Content that is NSFW should be behind NSFW tags.

-Content that might be distressing should be kept behind NSFW tags.

...

If you see content that is a breach of the rules, please flag and report the comment and a moderator will take action where they can.


Also check out:

Partnered Communities:

1.Memes

2.Lemmy Review

3.Mildly Infuriating

4.Lemmy Be Wholesome

5.No Stupid Questions

6.You Should Know

7.Comedy Heaven

8.Credible Defense

9.Ten Forward

10.LinuxMemes (Linux themed memes)


Reach out to

All communities included on the sidebar are to be made in compliance with the instance rules. Striker

founded 1 year ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 10 points 3 months ago (4 children)

So if these are people wiring their Christmas lights wrong, assuming these are led lights, doesn't this "solution" not work bc of the polarity anyway? Or is that only a DC thing with diodes? I only did okay in my physics electricity stuff lol

[–] [email protected] 10 points 3 months ago* (last edited 3 months ago) (2 children)

For simple stuff such as those lights, polarity is usually not a problem when using AC.

In case of AC (Alternating Current), instead of having a + and - pole, you have a Line and a Neutral terminal.

The Line terminal goes + ... - ... + ... - ... + ... - with time and the Neutral stays at 0.

When connecting to LEDs and such, you have an AC to DC converter, which tends to be fine no matter which pin you put in which hole.


Edit for clarity: I am talking only about the specific appliance in this case, having a 2 pin plug. When doing home wiring, polarity matters a lot.

Anti Commercial-AI license

[–] [email protected] 2 points 3 months ago (2 children)

Ah, so that's why it's half power compared to DC, makes sense.

[–] Pher 2 points 3 months ago

Kinda, it's half the power because the power goes like the temporal average of the current squared, the current oscillates like sine or cosine, and the temporal average of a sine or cosine squared is 1/2.

[–] [email protected] 0 points 3 months ago (1 children)

Unless the AC is a square wave, in which case stuff becomes different.

[–] Duamerthrax 2 points 3 months ago (1 children)
  1. Not really.

  2. Where on earth would Mains be a square wave?

[–] [email protected] 0 points 3 months ago (1 children)
[–] Duamerthrax 1 points 3 months ago (1 children)
[–] [email protected] 0 points 3 months ago

As far as the appliance cares, it is the only input power it gets at that time.

[–] Omgpwnies 1 points 3 months ago (2 children)

In household wiring polarity does matter, especially if you are assembling plugs. Only one of the three wires is carrying live current (hot), the other two are the neutral return path, and ground which is for safety. If you accidentally switch polarity, you can cross hot to neutral and cause a short circuit.

[–] [email protected] 4 points 3 months ago

Switching the neutral and hot pins doesn't matter except for appliances with exposed metal tied to the neutral pin, which is pretty much exclusive Edison screw lamps. This is why many plugs (especially those that immediately go to a rectifier) don't bother with polarization.

Swtching hot and ground is a problem

[–] [email protected] 0 points 3 months ago

My bad. I wasn't clear enough.

I was talking about 2 pin plugs, as shown in the post and how it is usually for those cheap lighting thingies.

[–] PolydoreSmith 2 points 3 months ago

No, alternating current doesn’t have a polarity like DC does.

[–] brianorca 2 points 3 months ago (1 children)

It would still work. But it is VERY dangerous. 1. The far end of the light string will now have exposed metal prongs that are energized at 120v, which can be fatal. 2. If the other end gets plugged into a socket, there is a 50% chance it will be a different circuit on a different phase, which can create a 240v direct short, across a wire that has no properly sized circuit breaker. 3. Using it to plug a generator into your house during a power outage can kill electrical workers trying to fix the outage if you fail to open your circuit breakers.

[–] [email protected] 1 points 3 months ago (1 children)

I knew that much, I was more interested in how diodes work on AC lol

[–] brianorca 2 points 2 months ago* (last edited 2 months ago)

In AC, diodes work half the time, every 1/60 second. The "good" LEDs will have circuitry to fully rectify the AC into DC, drop the voltage properly, and smooth the peaks and valleys, so they will be continuously lit. So the cheap LED Christmas lights might have a slight flicker, and the good ones are steady. (Or get fancy with chasing colors, etc.)

All of that happens inside each of the "bulb" enclosures, or sometimes in a box at one end, so it technically doesn't matter which end they are getting electricity from, since the socket at the far end is still just connected in parallel to the plug at the near end. (Otherwise you wouldn't be able to link them together.)

It's just a really bad dangerous idea to reverse them.