AC Polarity Explained - Electricity 101 

Me, while watching this: *laughs in european*

Thank you

So if you have a non-polarized plug with no ground even though you don't need to know, how would you be able to tell the hot and the neutral lines? Also I was told that non-polarized plugs have regulators that even if it is flowing in the wrong direction kind of like a trains point crossing or trains siding switches the line before it reaches the devices to provide the right flow. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1uEmX5XClPY.html

@@EliteMemes. +

@@randybobandy9828 obviously that didn't stop anybody here....

@@randybobandy9828 it was inspected. Inspectors don't test every outlet. They only look in the panel. It's not like it's a big deal... I fixed it.

@@Krankie_V same thing happened to me. Ruined a TV too.

@@Z3rostar sucks! I checked all the stuff out myself. I guess a previous homeowner replaced one receptacle and connected it wrong.

@@randybobandy9828 You can also be renting from a landlord who could possibly be hiring under-qualified/overworked electricians.

The voltage in germany is close to 240 volts instead of the 120 in the US. Makes the added safety even more necessary

@@lincolnhunt9558 European plugs are also never polarized.

@@Iisakkiik Are You sure?

@@janpf0624 In most counties yes they are not polarized but it does look like at least in France they are polarized. In my country (Finland) I have never seen a polarized plug.

@@Iisakkiik Better. France, Belgium, Poland, the Czech Republic and Slovakia have so-called "French plugs" - CEE 7/5 sockets and CEE 7/6 plugs. The socket with the "ground" pin upside, has the "hot" hole on the left and the "neutral" on the right.

That is true

MarcBerm, thank you, I was just about the mention that same thing. And by the way, I have been "bitten" by a lamp that was wired incorrectly with the screw part as hot and that is where I learned about polarized plugs. Lol!

@@jimturpin The same happened to me when I was a kid, scared the shit out of me and threw out the lamp thinking it was faulty. Now I remember that that power socket had the live and neutral backwards!

Make sure power is off from the switch before unscrewing it.

If possible always shut down electricity in the whole house

My boyfriend said your attitude about electricity is the right one. The first electrician he worked for told him, "Once you think you have electricity figured out it will kill you". He retired in 2018 after 36 years working around high voltages. He's still here and says he still hasn't figued it out.

I love electric shocks.

Very nice of you to say. It means a lot because I was "shocked" at how how much effort this one took, I had fun doing it but it took me forever. Glad you liked it.

Lol same but in a different country

Lol even I'm from India and still watching this ☺

You are not alone. Sydneysider here.

Same (but i'm brazilian)

😆

Unless the box was wired up by Uncle Grandad

Little is alive

I live for ever then

And polarized is for appliances with a switch. Now im smarter.

Thanks for that!

What do you think those possibilities would be?

Stringer, you have touched on a subject I have wondered about for decades, and get conflicting info on the internet, electricians, and other people who claim electrical knowledge. The heart of the misunderstanding is in your statement "if it was never connected to an earth ground, it would be impossible to electrocute yourself using power tools in a damp basement." That has always been my understanding which begs the question, why is the neutral connected to ground in the first place? To avoid frying your home in the event of a lightning strike seems to be the accepted wisdom. But the chances of that happening are remotely slim for most homes (and I think could be avoided by attaching a lightning rod to your home). Yet the chance of frying your body touching power tools, or using electrical devices while in the bathtub or similar damp places seems a lot more likely to kill people than frying your home. And could be avoided completely by not tying the neutral to ground.

@@SirDella the first, most obvious application would be power outlets that detected a wide variety of wiring faults, and could be reprogrammed in the field to detect and respond to even more. Smart power outlets could by default leave the outlets powered off, turning on power only when it detects a suitable load. Small children with probing fingers would be safe, and parents wouldn't need to buy outlet covers or remember to put them back. The most exciting use IMO would be in allowing unorthodox wiring schemes safely. In the UK many kitchens have an inherently unsafe ring circuit, relying entirely on plug fuses to protect them. Smart outlets could monitor the loads at every part of the circuit, and if someone plugged in an appliance that draws more power than the circuit can handle at that place, a phone app could tell them which outlet they could use at full power, or even provide reduced power to the appliance at that outlet. With electric cars becoming more and more popular, more homeowners will be faced with the choice of upgrading their home service drop to accommodate the very high power draws that recharge cars faster, and learning to live with what a 15A circuit can provide. Rather than add more full-time capacity to the grid, a smart panel could budget the same 100A circuit that most homes have to make sure that large loads don't overlap, while still allowing 99% of convenience. So you could get home to a house, plug in your electric car, cook a meal on your induction stovetop, run a load of laundry, and rather than need another 100A to charge the car, a smart panel would monitor your usage and deliver full power to charging the car after other loads weren't in use. Right now, so-called "solar generators" are using microcontrollers instead of fuses to protect their circuits from overload. If you try to draw too much power, or apply too much charging voltage, the device simply shuts down that circuit and gives an error code. When the problem is cleared, it reverts to working normally with no fuses to replace or breakers to reset. If you have one of these, think about how it would be to have your whole home working like that.

@@StringerNews1 About the plug protection, I have plugs that have a mechanism that requires both prongs to be inserted at the same time to unlock, it can be bypassed obviously but a toddler figuring that out is unlikely. As a bonus, it makes a satisfying click when plugging something in. I like the idea for electric cars, tesla chargers soon will do something similar but with the entire grid, not taking the home appliances into account. One could just set a low priority to the car socket and done, nice

@@kimstockdale632 it's important to remember that technology has improved greatly over the centuries since we first discovered electricity. Equally important is to recognize that change (or lack thereof) isn't usually driven by the availability of those improvements. The people who built your house, and the company that delivers your mains electricity are motivated primarily by profit, not safety. That we have any safety provisions at all is because consumers stood up to Big Business and demanded change. Unfortunately that commitment to consumer rights has wavered as political tides turned. And the compromises that we have had aren't the best that could have been done, not by a long shot. Lightning is more prevalent than you think. I wouldn't discount the importance of lightning and static protection, just the efficacy of the century-old methods. The other stated reason, protection against high-voltage primary wires falling onto lower voltage secondary wires is also something that can be addressed by other methods. Grounding was a simple solution for simple times when metals were the most common substance for making durable goods. Although metal appliances haven't gone away entirely, you're more likely to see metal that's insulated by durable epoxy paint, ceramic powder coating and vinyl overlays. Home plumbing is also insulated with plastics, more for cost and thermal insulation, but the end result is that it's a lot harder to touch ground in living areas. IMO we should use this to our advantage, and move deliberately toward insulation and not grounding to prevent electrical shocks. Worth noting is that 3-phase power is distributed (and consumed in industrial settings) in a balanced 3-wire configuration commonly called "delta." Delta power lines have been struck by lightning, but in part of the very high voltages, and because there's no path to ground in a delta circuit, disturbance to customers down the line is minimal. Local pole-mounted feeder lines at voltages of 7200V and greater start at a power substation as 3-phase delta, which goes to businesses that need 3-phase, and branch out into unbalanced single-phase that is then converted to 120/240V split phase by pole mounted transformers. It all goes wrong when the utility saves a buck by using the same common wire as the return for the primary high voltage circuit and the low voltage split phase neutral. Essentially the utility is connecting your home to all of the risks and none of the benefits of its high voltage distribution system (the one most likely to be hit by lightning) and puts the onus on the consumer to safely ground _their_ system! It wouldn't take much to switch to balanced 2-wire power right now in North America. While I wouldn't advise making toast in the bathtub under any circumstance, but for my money, isolation and insulation will keep more people safe from the real hazards that they face in 2021 than earth grounding can. Education will be needed to make the change. I've had people ask me to flip a wall switch because they were holding a glass of water, and in their minds they could get electrocuted somehow. People need to be better educated.

Jesus! Fire the electrition immediately!

At least it's not like USB that will insert on the third attempt

@@thenasadude6878 yeah lol

@@thenasadude6878 *laughs in USB-C*

That means they are double insulated.

we dont need them, our plugs are safe enough without

@@jacklewis100 weird to read that, while France has a polarized mechanical design and even a recommendation for the polarity, it is totally legal to wire it the other way around.

@@jacklewis100 Nope, the EU plug fits in nealy every socket without polarization. To be honest the North American plugs are so bad designed. I can‘t understand why this hasn‘t been changed yet.

that is because every outlet in Europe (at least Austria and Germany) is GFCI and AFCI protected. in the US only wet areas are GFCI protected (bathroom and kitchen outlets)

@@Sparks0001 UK plugs are huge and bulky... totally not convenient when i.e your laptop mains power cord need to stowed away in a laptop bag...

What about a house in 2020, they also don't have groundmost of the time.

@@Muxik4k all houses built in the 2000s MUST have grounded outlets and GFCI outlets outside, in the bathrooms, basement, laundry and kitchen

Glad it was helpful!

@@SilverCymbal Thank you so much 😊

@@HelloKittyFanMan. Thank god you are here to point this stuff out Mr kitty litter

Thanks 👍

Glad you liked it! Thank you

Thank you very much

How did it work with the wide prong removed?

@@ronaldbrown5745 It did work. We also use to break off the ground prong on 3 prong plug when the outlet didnt have 3 slots back then

​@@ronaldbrown5745 I think he snipped part of the wider prong

Nothing to do with the plugs, but some devices have capacitors in them to smooth out the power flow. When these are empty they suck a lot of power in very quickly so when you first plug them in, that sudden "inrush current" creates a spark. It's a similar principle to how a welder uses a lot of amps to create a spark big enough for welding. The capacitors also pull a lot of amps just for an extremely short time (they charge up *very* quickly) so you only get a small spark and the breakers don't pop because it's too quick. This is why if you unplug it and plug it back in again fairly quickly before the capacitors have discharged, you won't get a spark the second time as they don't need to pull as many amps to charge back up again.

"Polarity" here is misused, if only for simplicity's sake. Polarity only applies to DC (direct current) which is how electricity is stored in batteries where you have a positive, + terminal and a negative, - terminal. AC (alternating current) is what we have available at our outlets in the walls. In the United States, it is roughly 120 volts AC at 60Hz. In most cases. In other words, it measures 120V (there's an even deeper explanation of what the voltage REALLY measures, depending on what instant in time you measure it, and another deep dive into how you get 120 volts for most of the outlets and lighting circuits in your home, and 240 volts for your heating, air conditioning, stove and dryer all from ONE wire delivered to the power pole, or buried power source if you're so fortunate, outside your home), but switches poles, or polarity, 60 times per second.

@@godzillafirebox7765 oh all right, thank you for informing me! So far I have only used DC so that is why I barely know anything about AC. I can delete the last sentence of my comment. I look forward to working with AC in the future!

@@godzillafirebox7765 The plugs are widely called polarized plugs. It is not misuse.

@@okaro6595 There is electrical polarity and connector polarity. We each speak of the other. In other words, I agree with what you just said here 100%, and still stand by my statements regarding electrical polarity from 8 months ago. Without reference to ground, a pair of wires can present either an AC non-polar voltage, or a DC voltage with a positive and negative lead. Also, is 240v in a home (that which is center tapped in a transformer to create the two phases of 120v with the center tap tied to ground & also strapped across in the breaker box and called neutral) considered "polarized" for some reason? I'd genuinely like to know, and if so how, other than its position in a connector would you know which pole you are dealing with simply by measuring it with a meter?

In the US and Canada or some reason we only have RCD's in the bathroom and kitchen.

If you mean the ground prong, the round one, then it causes no danger as it connects to the equipment case. For safety you still might turn power off if something unexpected happens (like you rip the socket from the wall)

Ridge side is the neutral side. However, if the plug doesn't have a big prong, you don't need to anxiously figure it out each time. Just plug it in, it'll be fine. It won't hurt anything electrically, and the device will have been engineered to avoid any risk of shock.

No, the polarization with the wider prong has nothing to do with grounding. They are NOT grounded. If the device is grounded it is done with a separate ground prong.

@@okaro6595 You are correct, they are not 'grounded' with the same protection afforded by the green (or bare) conductor. However, the case is tied to the neutral (wide) blade to prevent the chassis/case from becoming 'live'. The only 'ground' path provided by a two-prong wide blade is back through the neutral to the power panel, then from the neutral bus bar to the ground bus bar. Rather lengthy yes, but at least the case is never 'live'...

Answer to your question: Wear Rubber Gloves.

The ground prong is essentially just a safety feature, which shunts any potential from the metal casing to the ground. This is how RCDs know when to trip (if there isn't equal current flowing in as there is out, there is a leak somewhere, in other words, the device is broken and shouldn't be in use, but those faults are cheeky. And that leak is through the device to the ground. Thus, without a ground, an RCD won't trip, and thus the device's casing will stay at high potential waiting for something to shunt it. This something could very well be the next person to touch it.) So a missing ground connection might not be a problem unless the device breaks. However, it depends entirely on how the device is constructed.

In Europe plugs can be plugged either way. Here people are instructed to unplug before changing bulbs. I do not even turn the switch off.

This video didn't really address how that works. The hot pin is where the energy comes from, alternating 120v back and forth from the neutral. In this regard, your statement is correct. However, the neutral returns the energy back to complete the circuit. It has no energy in itself. Therefore it is safe to touch (by itself). If you touch the hot and are grounded, that electricity tries to complete the circuit through your body. This doesn't happen if you touch the neutral line. Hope that helps.

The neutral stays at zero volts relative to ground. The hot alternates between a high positive voltage and a high negative voltage relative to ground.

There needs to be a closed circuit for the lamp to light, which there isn't since the switch is open. However, the electrical potential still is present at the light's end. Thus you could get a nasty shock out of it in certain cases even though it appears to be off.

If the ground prong breaks it is dangerous. Never used damaged electric equipment. This has nothing to do with possibility to reverse the plug.

It might be a manufacturing/logistics/cost thing. I imagine the manufacturer of your glue gun makes many different products, and some need polarized plugs and some don't. It's probably simpler and cheaper to just buy polarized plugs in bulk and use them on everything (since the polarized will work on everything but the non-polarized plugs are dangerous on the wrong appliance). So, then, their inventory doesn't have to track two different kinds of plugs and worry about supply for building glue guns vs (for example) hook-hanging incandescent work lights with a switch... they can just always make sure they have enough of one kind of plug, and if one mfg line needs more at one time and another needs less, they all just pull from the same inventory pool.

@@GasBandit Nice Idea, never thought of that. They probably making desk lamp or something since It's just generic brand from gift shop store.

Very kind of you to say thank you

This method is much safer and more reliable. It should've been made a requirement back in 1962, instead of polarized plugs.

Toasters have the wires accessible so they must be cut securely.

It's also required in countries where the plug is not polarized, like most countries in Europe