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Hi. Why do we ever use AC to power homes instead of DC?
Haven't I showed you that AC is typically more dangerous than DC?
[Painful Gurgle]
Can we run everything on DC?
Yes! In fact pretty much every device at home has to rectify AC into DC
first before it can use it so why? Why am I angry?
The reason is elementary. Once there was a fight between a guy named Nikola Tesla being AC and Thomas Edison
being DC and Tesla won the contract on his employer Westinghouse company to provide power with AC
no matter how hard Thomas Edison tried to expose the dangerous nature of AC by
electrocuting dogs and elephants in public.
Wow
Now I remember why I'm angry; this Edison guy was an animal! He even invented the electric chair to execute with AC
--not because it was a cleaner or better way to execute--because he wanted to deface AC by forever associating it with death.
Nikola Tesla very rightfully won this battle.
Yes, AC can be more dangerous than the same level DC but a higher level DC can be as dangerous
if not more and just because something is dangerous
we don't stop using them like for example if you live in a high-rise
you are not in a constant risk of jumping off the window. But is there an advantage of using AC?
I mean, back then all they wanted was light using incandescent lights and those don't care about AC or DC.
Here I'm running a regular light bulb on AC as usual
and here I
S**t
S**t
I killed it.
Don't short s**t.
Anyways with this I'm converting the AC into DC using
It's a single diode, but it will do and if I measure the voltage at the output
F**k
S**t
Holy f**k the capacitor
Ah f**k
F**king piece of s**t
Anyways i'm reading around
170 volt DC and although it's still quite dangerous
I can still touch it and it's not as remotely as painful as touching the 120 volt AC
and the lightbulb
Runs on it just fine
And it's even a little brighter because it's 170 volt continues
Beside the lights the electric motors were becoming more popular in home
Appliances like meat grinders or fans and such, but even those could be made into brushless
AC or brushed DC for example, of course a brushless AC motor like this one that I took from an old
microwave oven can last much longer than a brushed DC...
(S***,F***)
Loose wires, avoid them anyways brushes in DC brushed motors wear out eventually
And that's why AC motors can last longer, but beside that fact there doesn't seem to be much preference between AC and DC
But the real advantage of AC is not at home
It's before electricity even gets to home in transmission lines
And that's why Edison's DC power distribution system eventually died away, here
I made a transmission line using thin wires and using my supply
I'll try to place 10 volts across my 1 ohm load for 10 amps of current
And I'm measuring the voltage across my load. Let's try it
See the voltage is like
seven and a half and you see my
Transmission line is starting to smoke and heat up and the voltage continues to drop see the line resistance is so much that the voltage
Across the load doesn't even get to ten volts
It's at seven volts for seven amps through the load and because of the high resistance. It's heating up so much
Similarly because Edison was passing low voltage across the transmission lines a ton of current was passing through the lines
And there is a limitation to how thick you can make the wires before they break under their own weight or become too expensive
Huge currents through the resistance of the wire would result in large voltage drops over longer distances
And that's why Edison's system could only transmit power to around a mile or two from the power source
Otherwise the power loss would be so much over the lines
That would cause huge inefficiency, of course Edison was aware of his s**tty system
So he decided to let one of his genius employees to take care of the problem, who was our beloved Nikola Tesla
He was working for Edison at the time. according to Tesla Edison promised him
$50,000 which was a lot of money back then, if Tesla was able to make great improvements to Edison's DC system
Which Tesla did in a few months and when he went to Edison to ask for the money?
He said "Haha. I was joking obviously you're not aware of our
American humor," which Tesla said "F*** you, I quit !!!"
Later Tesla came up with his genius system and developed it for Westinghouse company
What he did was to transmit power much smarter. He used AC so he could change the voltage level using transformers, here
I'll use my auto transformer to generate 10 volt AC which would result in 10 amp AC through my 1 ohm load
But before I send it through the transmission line, first
I'll step the voltage up using my microwave transformer
and then I would step the voltage down after the line if I had a transformer
Well, guess I can borrow the one from our microwave
F**k. They're using tamper proof screws to stop me
What they don't know is that nothing can stop me. They are just postponing the inevitable
There we are...
I'll just take a picture of the wiring before I pull it out. I don't want to blow it up later
There we are
Ok, now we have both transformers connected. Let's do some voltage measurements before I connect the load. At the input
We have close to 10 volts so that's good. On the transmission line
We get around 190-200 volts. And at the output
Again we have close to 10 volts so that's pretty good. Now, let's connect a load
Ok. And the voltage across the load is
1.6 volts? That's garbage. What happened? The transmission line voltage
118 volts? Everything dropped
This is worse than the DC system. What's going on Tesla? Let's measure the transformer secondary winding resistance
Around hundred ohms. No wonder
There's too much drop over the large resistance of the secondary, so these transformers are not made for this purpose
That was a bad example. It doesn't matter. I'm gonna transmit power. No matter what
2 volts. 3 volts
4. 5. 6. 7
8. 9
And 10 volts across the load. We did it
And our transmission line is not burning so that's always a plus
Nothing is exploding. What is the transmission line voltage now?
820 volts!!! Well anyways, although
This is a pretty bad example, you can see that
I'm transmitting more power than the DC system
But my transmission lines are not burning. So, that's sort of a success?
See in this system
I can transmit a lot of power in this case around hundred watts without having to thicken the transmission line wires
And if the Transformers were better the efficiency would be higher, too
In fact, in this system, the higher you convert the voltage to, the easier it is to transmit power over greater
distances, with some limitations, of course. That's why in real life, they convert it to 10 kilovolt or hundred kilovolts
Why? Because in transformers, the input and output power is
ideally the same, although not really, because there's always some power loss as you saw, and power is voltage times current
So, for example, if I increase the voltage by
20 times, in order to have the same power, the current has to drop by 20 times at the output of the
transformer and over the transmission lines. And because the power through a resistor is equal to resistance times current squared
The power would be 400 times less wasted on f**king wires
F**k
And with high voltage comes great responsibility
The transmission lines have to be placed far enough so no arcing happens
There is no easy way to do the same thing with Edison's stupid
DC system. In order to change the voltage, you would have to convert DC to AC,
increase the voltage, and then convert the AC back to DC, and lose a lot of power in the process
Edison still couldn't see this. All he saw was that his company was losing the contract of his life to power the world
So all he did was to grab the fact that
Tesla's system was running on super high voltage, like 10 kilovolt or 100 kilovolt, and say that it's super dangerous to people
by electrocuting animals with 10 kilovolt in public
Thomas Edison. He contributed a lot to science and technology what he was also an a$$hole
businessman, and that bit him in the lower back area
the moral of the story, don't be an a$$hole
GIVEAWAY TIME!!!
You know, CircuitSpecialists has been quite nice to me providing all my basic tools and components and everything
And I really hope you find what you need In their website too
And, I'm quite happy with the multimeter they sent me, which is an LCR meter. It measures inductance, capacitance
resistance, voltage, current, and a bunch of more stuff. So thanks to CircuitSpecialists
I'm gonna give away five of these to my patrons at patreon.com
and you the viewers. Also, if you want to start electronics you would need a lab power supply
And I'll give away four of those too. As usual, my patrons are automatically in the draw. For everyone else
please follow the link to the Google Form in video description and let me know which one you need and I'll draw your name
and that's it. Unibrow out