Why is the mains supply alternating current?

Tesla solved the problem of how to tansform power up and down to send it over long distances.

The fact people profit from churning out cr4p is down to opportunism.

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Solved one problem and created another imo.

Wonder whether there's some way of hooking the laptop up to a bicycle dynamo. That way you'd be generating a direct current, so you could tell the Chinese where to stick their crappy adaptors AND be combating obesity at the same time.

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I heard / read(?) a great programme about Tesla the other day.  Explained all about how he founded AC from DC.

Do you know of it, Mac?

Radio 4, I think.  Might have been the World Service.

Apparently we are only just catching up with Tesla's work.
He 'solved' loads of stuff that were so far ahead of his time that the problems hadnt even been discovered yet.
Allegedly it was JP Morgan that stifled his innovation in his own pursuit of money.

Even if it was DC you'd still need a power supply. Chips don't like 200 volts, they melt.

DC is far more dangerous, be a lot more dead people.

AC is handy anyway for things like AC motors.

Jul 3, 2016 -- 8:33PM, dustybin wrote:

Apparently we are only just catching up with Tesla's work.He 'solved' loads of stuff that were so far ahead of his time that the problems hadnt even been discovered yet.Allegedly it was JP Morgan that stifled his innovation in his own pursuit of money.

Correct.  JPM suppressed Tesla's work BIG TIME - according to the show I heard.

it has to be AC to cover large distances, too big a voltage drop otherwise..is that right?

The genius of Tesla - pity he and Edison (mega-genius-leech) fought. 

I think he liked cats.

Tesla was a bird man apparently.
The feathered variety not the fleshy human female sort.

Just goes to show what can be achieved when you live a celebate life and don't give in to attention seeking women.

Nietzsche implied that it was more important to do great work that create spawn.

He didn't think that while he still thought he had a chance of getting in Lou Salome's knickers.

DC current was trialed in the USA. But phased out. Killed a lot of people and it lost power over distances.
Is the future broadcast power?

Transformers only work on "alternating current"
That's why you see Power Stations/Sub Stations with huge transfomers.
And please don't tell me Cars have DC Volt batteries ..like in the old days with sets of points !!!
..because when you pulse DC from 0 volts to + 12 volts the waveform acts like AC !

Fair enough. I suppose it's the transformers in the devices themselves which are critical here. If you delivered a direct current to people's home, they could have either washing machines and room-sized computers, or electric toothbrushes and laptops, but not both.

Enjoy it while you can as we are running on empty.............

Jul 4, 2016 -- 2:13AM, lfc1971 wrote:

it has to be AC to cover large distances, too big a voltage drop otherwise..is that right?

NO Not really ,HVDC is used to transfer power over long distances ,but its all about cost ,High Voltage DC is very adaptable into other systems and can be inverted to AC to fit any network .

Ib Sonko DC is far more dangerious ....no not really,AC is far more likely to cause death by contact but DC can be a cause of death due to fires ect  ,i reckon homes will in the future will be all DC ,DC is utilised in all electronics and all the changes from ac to dc are very wasteful of energy ,not at all effiecent ,in fact in the future houses will be able to be off grid very easily and reckon massive savings will be available ,all led lighting and direct dc fed TV,s and Computers ,fridge/freezer is a problem but reckon there will be further devolpments in that area soon .

Bodil ...cats you say ,i knew there was summit about him ,apparently eddy had a giant revolving table with compartments innit and if he got bored he put what he was doing away and spun the table .Took about 5000 experiments  to get the lightbulb ,it was all about experiments and patenting asap.

Zorro ...phased out

rockin ....pulsed dc can never be ac and its not possible to store ac in a battery ,the huge transformers are needed because of the load required imo ,not because the change from 410 3 phase to 240 single ,think the uk is 1100 ,410 ,240 although technically others are easily avail .

The OP mentions flakey Chinese electronics ...try BIGCLIVEDOTCOM ,he is very good ,top bloke ,anyone who thinks they have a grasp of electrics have a look at his stuff ,big clive hates chinese junk but he actually is a clever man ,for example look at his RCD stripdown

I beg to differ bnb, when you touch AC it tends to throw you off but with DC it causes the muscles to clench meaning it is harder to let go and usually means you suffer a longer duration of electrocution.

please desist from tarkin sh1t .TIA

https://en.wikipedia.org/wiki/Electric_shock

Edison actually helped produce the electric chair during the "war of the currents" as propaganda in the DC v AC battle .

he killed all sorts of animals including the two legged type ,the above link explains that the lethal level of ac is lower than dc due to frequency .

rockin ....pulsed dc can never be ac
I never said it was ...but you can pulse DC and then transform it !!
and its not possible to store ac in a battery
Stating the obvious..well to me anyway
,the huge transformers are needed because of the load required imo ,not because the change from 410 3 phase to 240 single ,think the uk is 1100 ,410 ,240 although technically others are easily avail .
UK transmission voltages are 400 kV and 275 kV; distribution voltages are 132 kV, 66 kV, 33 kV, and 11 kV.

RockinRon ...qualified ONC Electronics,
Ex - Employee (Electronic Design Engineer) Philips, Plessey HV systems, APT (All Power Transformers) Marconi, Ultra Electronics...to many to list !
Worked in Electronics/Power Industries for about 7 years .
Now as a hobby I design and build Guitars and Guitar Amplifiers !
So I don't need any numpty on here telling me how AC or DC works - got it !

^ that seems fair.

but i would have expected at least an HNC from you rockinron.

or perhaps the full time equiv. HND

Thought i remembered reading somewhere that for a DC supply they would have needed sub stations on nearly every street.

I've a DC Battery, I keep it in a cupboard with my tartan paint .

Pulsed dc is by definition a form of AC, just square wave not sine wave AC

Though why you'd have a supply thats like that would be beyond me.
I think it's a safe bet we'll have AC supplies in 100 years. The cost of changeover would be horrendous.

"but i would have expected at least an HNC from you rockinron"
In life your career can take many odd twists and turns ...as circumstances prevail -
As example - I was watching this programme on the Telly (program surfing)it was about a brilliant Australian Surgeon - now he started off in life as a "Toolmaker" in the UK ..I mean how wierd is that ?
So here we go ...
My brief CV -
Apprectice Aircraft Technician - BAC Weybridge (No Orders for VC-10's, only a few Orders for BAC 111, TSR-2 cancelled )
So I thought gotta get out of here ...so Electronics a thing of the future ..into Electronics I go - worked for Companies as previously stated ...got ONC , then someone said ..big money in the Oil Industry ...so in I went (that's why only ONC in Electronics) ..But I have HNC Business studies.
30 Odd years in Oil Industry - Major Equipment Specialist (Columns, Towers, Reactors Heat Exchg.)
Then did a couple of years in Oil Industry Equipment Sales .."Sales Director" Offices based in Mayfair.
Porsche Company Car ..then XJS then Rolls Royce (I also owned a Ferrari 308 GTBQV) to name but a few.
Couple of years - Merchant Banking in the City ...(Projects financial technical analysis specialist) six figure salary.
A couple of years Derivatives Day Trading (CFD's)...with CMC
FUBAR ...
Now Semi retired phucking about with trading (Arbitrage) on Betfair.
But still trying to put the odd deal together in the Oil Industry ...

its do you know who i am time ....yawn feckin yawn ,your a donut ron ,thats what you are ron

can pulse DC and then Transform it !!!

you can pulse it and transform it all you like ron but its still feckin  DC ,if you mentioned inverting it ok but even then its not true AC

now stop waffling and giving it the "do you know who i am " 

Worked in Electronics/Power Industries for about 7 years . what did you do ,make the tea ?

Lend us a fiver Ron

Ron thats a very impressive lifetime of work and experience, and good times i am sure.

it sounds like the guy has SIS in his house ,this can alter the current?

No further posts on this subject ...it's infected with numpties - you know who you are - you're not worth my time.
And back on subject - Why is the mains supply alternating current
Just Google it ..you'll get the answer.

I never said it was ...but you can pulse DC and then transform it !!

its still not DC ron ,all the oil deals in world dont make you right ron ,all your money and all your cars , property portfolios and your still wrong ron ....i have no formal qualifications in anything ,but it still does not make me wrong and you right .


just climb  down out your rear ron and admit your wrong and we can all be pals again and move on 

OK idiot ...one more post ...
My Quote:
"because when you pulse DC from 0 volts to + 12 volts the waveform acts like AC"
Unquote:
Acts like ...not is ..it's pulsed DC not AC..I never said it was AC
Now got it  T W A T

The birds would be electrocuted if they were to sit on DC power lines, and tesla was a bird lover and thats why we have AC?

have you noticed birds always face the same direction when perched on powerlines?.

Got a replacement adapter.
Made in China.

Will probably be reviving this thread in a couple of months.

Would it ever be practicable to hook up all these modern DC devices directly to solar panels on the roof? The way panels are configured at the moment, with an inverter needed to convert the current to AC, then an adapter to convert it back to DC, just seems so wasteful. Particularly as the inverter is probably made in China, so that's another part likely to wear out in six months.