Difference Of Electron Flow Thru Ac & Dc, and at what speed?

I am getting the impression that amps are rather useless...is this the case? They only use them to kill people? Do they serve any other purpose? What is the juice that makes whatever you plug in work? Is it the volts? Are volts harmless?

Are peoples' homes set up to get the most out of their electricity? I just read somewhere that ordinary lightbulbs use 5% for the light and 95% is lost in heat. (The new kind is supposed to be better.)

Volts don't go anywhere. They are the potential which drives the charge (coulombs) and the result is a flowing current (amps).

Talking of volts or amps as 'things' can only be confusing. It would almost be acceptable to talk of coulombs as 'things' as they are a direct measure of a physical quantity.

Using the water analogy (which is inherently flawed if you get more complicated), if you have a river with flowing water, the difference in height between two points are the volts. The water which is moving is the charge (coulombs). The flow rate (amount of water passing any particular point per second) is the current (amps).

I hope this helps

@precursor

Wrong --- try a dictionary. Magnetic materials are magnetic, and many are non-ferrous. Ferrous means IRON, period. Some ferrous materials are non-magnetic (stainless steel).

Maybe you meant ferromagnetic, which is totally different.

My household breakers are 40A @220V (dryer) 40A @ 220V (stove) and 60A @220 split for the 110V circuits. That adds up to 30,000 watts worth of breakers, but of course I can't use that much.

1 100 watt lightbulb uses about 1 amp. What do you think your 1000 watt microwave uses (10 amps) ? How about your dryer? Your hair dryer?

Bad wiring will DECREASE your electric bill since less amps will flow. You will dissipate more power in the wires, but less power overall since there will be less voltage at the load. Inefficient, but true, until your house burns down.

Look at your last power bill, it is maybe in Kilowatt-hours. That is how many hours it would take you to consume that much energy if you ran a 1000 watt load. (my bills are upstairs and my wife is asleep, so I have no example)

Wrong, tesla coils operate on resonant transformers driven at high frequency

Where do you get this stuff?

Wrong --- That's a Van de Graff generator

LOL do you have any idea how much power the device used? Any idea what you are talking about? Any idea of the power available to a commercial 220V feed?

A million volt generator doesn't need to consume much power.

Where do you get this stuff?

@Empress

Amps times Voltage = power, so 110 Volts times 1 amp = 110 watts. Run it for 1 hour and you used 100 watt-hours of energy, (or did 100 watt hours of work).
1 horsepower = 746 watts.

A high voltage source may have the capacity to deliver high currents, or not. The more current it can deliver, the more work/damage it can do.

The higher the voltage, the more likely the strong fields will ionize gasses and cause dramatic effects. You can create plasma arcs in a microwave oven because of the high voltages created by the standing waves (google grape microwave).

A 1 million Volt Tesla coil that can supply 100 uA of current would only need a couple 100 watts (assuming 50% efficiency).
Here is an analysis of a small tesla coil
http://www.tesla2006.org/presentations/oth...20Apparatus.pdf

Amps are just as important as volts. They work together.

Using the hydraulic analogy for electricity (which has been posted to you before, I think) think of voltage as the water pressure, and current as the water.

So, lets say we have a very high pressure low flow system ( a pressure washer). Can't do much work, can't knock a person down. But, it is very high pressure. (high voltage, low current). It can do damage at the point of contact (like a small tesla coil)

Now, assume a fire hose. It has decent pressure and huge capacity. It can knock you on your ***. Like a household main (especially 220V)

Now, assume a big bucket of water you can throw. Pretty high volume, much less pressure, and runs out quickly. That's like a car battery that can start your car.

Those analogies obviously have limitations, but should give you the idea.

This post has been edited by meBigGuy on Dec 13 2007, 09:05 AM

It's useful depending on what it is you need it for. Motors utilize amps (current) to turn where more current will result in stronger electromagnetic fields which result in a stronger attraction/repulsion force which result in a greater torque value. More current through a light will cause it to shine brighter.

But "loads" like any have a resistance value all their own that (for the most part) doesn't change (unless something is done to the device itself). So what happens when you increase the voltage but leave the resistance the same? Current will increase.

Loads usually come with power ratings. A max voltage and max amperage, and the reasons vary slightly but for the most part remain the same. An example is a switch. The max amp rating is the most it can carry for a sustained period of time. Higher and you run the risk of over heating resulting in damage. The max voltage is the most it can receive and not arc. Volts are the 'driving force' and with enough you can actually get a discharge across a switch that isn't even closed.

Essentially it is volts since it is volts that drives the current. Current tends to be the result of when you apply a voltage to a resistance. After all E/R = I where E is volts, R is resistance and I is amps. Increase the resistance and you get less current but increase the voltage and you get more current.

When it comes to the home you should think of appliances and wiring separately. The wiring in your home (provided it is up to code) is set up to get the most out of the electricity that enters.

When it comes to the appliances, it comes down to you and what is available. Incandescent bulbs do lose most of their power as heat while very little goes to lighting a room. This is what makes the new kind better. Instead of heating a coil up to the point it glows, you pass an electric current though a noble gas mixture. The electricity is used to excite the atoms causing them to give off photons (light) instead. More more energy efficient than heating up an element.

That depends on what you mean. When it comes to amps, you are talking physical objects (electrons) and not a force, and such physical objects do the moving. However the electromotive force is felt down the wire almost instantly (as opposed to the relatively slow pace of the individual electron (DC)) the moment the battery is connected. The electromotive force does actually travel (as forces can) and a perfect example of this is kinetic energy with regards to the table top toy. The ball comes down, hits the one next to it and the kinetic energy travels through all the other balls till you get to the last one where that one gets 'pushed' up and away.

First off, how you "add" up voltages and amps depend upon circuits in series and/or parallel. For instance if you had a batter connected to three resisters in parallel, each resister will feel the full voltage from the battery. So a 6V battery will supply 6V to each one. That DOESN'T mean you have 18 volts. If say the total amps was 3 amps then each resister (provided they are of equal ohm value) would have only 1 amp across each one.

But if you have three resisters in series then each one will feel the full 3 amps. That DOESN'T mean you have 9 amps. So if you have three sets of three that doesn't mean you have 9*18 = 162 watts. You still only have 6 * 3 = 18 watts.

Also if you look at the wire that actually enters your house, it will have three wires wound around each other to form a single cable. This has to do with phases (with regard to AC). You can take a single phase and have 120V or you can take two phases and have 240V or you can take all three and have 360V.

As for the amps. That is the MAX load that can be applied and not trip a circuit breaker or blow a fuse (where such devices are used to prevent damage). It DOESN'T mean everything (or anything) you plug in will automatically use that many amps.

Again, amps depend not only on the voltage but also the load or device.

Current through a wire will produce a magnetic field. This (in bad wiring) is called EMI (electromagnetic interference). This can actually induce a current from one wire to another through insulation. It would be like having a light bulb constantly on which will use power and will cause you to have a higher power bill. When insulation degrades enough you get a short (often as a spark) which can ignite surrounding materials. Ever hear of fires cause by bad/old wiring?

When it comes to certain appliances, they require much more amps and so they will have a direct line from the fuse box which a higher amp rated fuse/breaker in place at the fuse box. These wires will, of course, be thicker than those that go to your wall socket (the 110V 10A).

As for the tesla coils. They gather a static charge. Once the charge becomes great enough to overcome the resistance value of the air, the charge will 'discharge' and such is seen as the lightning that comes off the coil. As I said I don't know exactly how the big ones work but for the small one that we took apart in class, it was a rubber belt driven by a motor with a comb in the globe that rubbed the belt as it spun . The friction gathered a charger to the comb where the comb was connected to the globe. Touch the globe and you gather the static charge as well until you touch something with a lower electrical potential than you and ZAP. The big ones still generate a static charge, they just use stage up transformers and capacitors.

No No No. That like saying that pressure is more important than the water. Makes no sense. Voltage and current combine to produce power. You can say you apply a current to get a voltage. Keep the current constant, vary the resistance. The voltage varies.

You cannot say apply a voltage to a resistor is any more correct than apply a current to a resistor. Decrease the current and get less voltage. I have supplies in my lab that supply current. You set the current. You are just used to thinking in terms of constant voltage. It is a perspective, but not precise. They are two wings of the same bird.

More ignorance. 3 phase 220 is 220 phase to phase and 110 phase to neutral. (well, it can be delta or Y connected, so there my be no neutral) But, Nearly All houses are wired with 2 phase 220. Two hot wires and a neutral. They are 220 phase to phase and 110 phase to neutral. That is why there are usually two columns of 110V breakers. One for each phase.

Again, your 10A number is ridiculous. 1 1000 watt microwave oven consumes 10 amps at 100V. I can show you a 1800 watt hair dryer for cyin' out loud. http://direct.tesco.com/q/R.100-2853.aspx

See this for appliance power.
http://www.absak.com/design/powercon.html
http://www.cornhusker-power.com/householdappliances.asp

You really don't have any serious training in any of this, do you. EMI in bad wiring? You have no idea what EMI really is. And There is no way that "fields" can cause currents which will be detectable on your power bill. If you want to go into detailed analysis of this, I'm game, but the idea is flat out ludicrous.

That is nearly the most ridiculous thing I have ever heard. While fields can induce currents, it has nothing to do with bad wiring, or with EMI "induced" by bad wiring. Where do you get this stuff. It's ridiculous.

This is not what causes most household fires. Most fires are causes by bad or oxidized connections which create heat, which further degrades the wire and connection and insulation. Shorts can happen, of course. Usually a short will not cause a fire because it throws the breaker. It's the high resistance contacts that are the most dangerous (Especially those in aluminum wire to copper terminals that oxidize)

No No No. what you took apart was a Van de Graff generator. Tesla coils are transformers driven by high frequency AC. PERIOD. Look anywhere on the net, or follow the link I gave to the tesla coil analysis presentation. You are totally, absolutely, no doubt, completely wrong on this. I know what tesla coils are. You do not. You are guessing. Do some real research. Follow the analysis link I gave in the previous post. You won't understand it, but look at the pictures.

Hmmm....seems to be differences of points of view on Tesla coils. Is there perhaps more than one kind?

The water analogy does make the most sense to me, and yes, someone mentioned it before. I was wondering how far one can carry that analogy. I go into our back yard and pick up the hose, a plain hose with no sprayer so I have to put my thumb on it to increase the pressure to get it to spray farther to reach the plants in the back. High voltage, low current...O.K. What would my thumb be?

Ah, I have seen a great deal of confusion on the matter of electricity and not just here. I think there are more people who understand the main jist of relativity than electricity. I wonder why that is since we have had electricity for over 100 years. I include myself in this because for years I used electricity and never ever thought to ask what it is. No one ever does. (I am getting funny looks from family members for bringing it up.)

Nope. tesla coil is a tesla coil. Basic principle is the same for all. High frequency resonant transformer. AC and resonance was Tesla's thing. That rubber band static thing is completely different. No Doubt about it.

Your thumb is increasing the voltage without decreasing the flow much. That's like turning up the voltage in the power supply. Or adding batteries in series.

Ask people how a car works. Ask people how your toilet works (why does water stay in the bowl and then run out completely when some is added). Ask people why water freezes. Ask people why oil and water don't mix.

Ask people what a flame is. (the actual colorful wiggly thing --- what causes it and what are the different colors about)

It goes on and on. People understand little about what surrounds them, even non-technological things.

But, I think you are wrong about relativity. People think they understand, like electricity. Very few non-physics students really understand the twin paradox. Or how light is bent by gravity. Or why the clock in the top of the skyscraper goes faster than the one in the basement. Most think e = mc^2 is relativity. I suppose more can say E= MC^2 than E = IR. But they don't understand it.



This post has been edited by meBigGuy on Dec 14 2007, 05:58 AM

First off, I am taking a course on this as we speak. It's all text book answers (no google parroting that you are doing).

How do you produce a current? You apply an electromotive force. It's pretty cut and dry (oh so dry ^_^zzz) stuff. What does a battery do? It produces an electromotive force chemically. How does a generator produce a current? The wires, when cutting through a magnetic field, will create an electromotive force (Lenz Law). Once you generate the electromotive force to a wire, you can then apply loads to that wire. Depending on the load, they will give you the current that passes through the wire. However current generates heat which can cause extensive damage and so as protection we have fuses with amp ratings. There are two types. Instant and time delay. Although different, the basic principle remains the same. When too much current passes through the heat will cause the connection inside to fail. Circuit breakers are different. There are three types; thermal, magnetic and thermal-magnetic.

Ignorance is right. We use three phase starters to start the aircrafts we use. They have an effective voltage of 220 (each phase) which can allow us to have up to 660 Volts (effective).

You should really leave this thread before you embarrass yourself any further. Once again I will explain so you get it. 10A is the max allowable current. As stated, you have 110 volts. If you put a load that is 1 ohm, guess what? You will get 110 amps but guess what that will do? Blow the fuse/trip the breaker. Why? Because you went 100 amps over max. Appliances (loads) that you plug in will have such a resistance as to keep the amps down. It DOESN'T mean that no matter what appliance you connect, you will get 10A worth of current. It only means that the plugs can handle up to 10A MAX.

Another thing, with the plug providing 110V but the appliance only needs 24V do you call up the power company and tell them to turn down the power to your house? Of course not. The appliance will have a circuit board (containing at least one transformer) that will drop the voltage. It will also provide a resistance (resisters in the circuit) to drop the current. If need be it will also incorporate diodes and capacitors to change the AC to DC (rectifying circuit).

Do you even know what a phase is? Look at a sin wave on a graph. A complete wave is when the line has finished traveling both up and down and has returned to neutral. Lets say neutral is 0. The wave begins at 0, curves up to the peak +V then back passing 0 to peak -V then back up to 0. That's one complete wave (one cycle). The distance of that cycle is measured in degrees so one cycle is 360 deg. Phases are offset (not always) in measurements of degrees. So the military uses 3 phases that are 90 deg off from each other. However if you really want to get specific, if you have 3 phases and each phase is 220 then that would give you a peak to neutral of 311.174V Which will give you 622.348V peak to peak.

NOTE peak to peak and NOT phase to phase. 3 phase may have anywhere from 0 deg to 359 deg phase to phase difference. Peak to peak refers to the distance from the top of the wave (peak) to the bottom of the wave (other peak). This measurement is in Volts. You can also have peak to neutral which is referred to as just peak. There is no such thing as phase to neutral.

EMI is electromagnetic interference. When you pass a current through a wire you generate a magnetic field around that wire. In DC there isn't a problem but in AC there is. Each time the current cycles, the field will reverse but to do so it must collapse and reform. As the lines of flux expand and collapse upon the wire, this causes a neighboring wire to cut through the lines and Lenz Law comes into play. This is where insulation comes into play. Ever see a string of letters and numbers on a wire? The first letter (which should be the first digit in the code) is the E3 letter and is what tells you what the insulator is capable of with regards to shielding against EMI. That is only one. Another is when the supply (hot) and return (ground/cold) are next to each other. The insulator (being a dielectric) doesn't allow current to pass but as the insulation breaks down (cracks, peals, etc.) it doesn't offer the same dielectric properties which can result in a mild current passing through from the hot side to the cold.

It's called a first year university level course. Unlike the .9r thread, you or anyone else can't pretend to have a higher education when spewing forth the ignorance you have displayed thus far.

Go ahead (while you are googling) and look up static charge.

Look at any tesla coil in action. There is a "globe" or "coil" where the electricity arcs from. What is happening is that particular part of the tesla coil is gathering a static charge. When the charge becomes great enough (charge is measured in volts by the way) the emf (electromotive force also referring to volts) becomes great enough to overcome the gap between the charged portion and the ground. So the static charge will discharge once the electrical potential (oh look at that, also referring to volts) between the "globe" and ground is great enough.

Does it take a power grid to accomplish this? No. It only takes time. So as long as the generator is creating an electromotive force, current will flow and a build up of charge will occur. Now as I said before, the big ones work differently and utilize a transformer to up the voltage and capacitors to help store charge but you are still generating a static charge that will discharge with the arc method.

There are three methods to discharging. Bonding, direct contact and arc.

Do you even know why the tesla coil is hooked up to an AC power source?

Your thumb is increasing the voltage without decreasing the flow much. That's like turning up the voltage in the power supply. Or adding batteries in series.

How about, your thumb is a resistor. However in that particular situation, the current is not allowed to change (in an electrical system it would as voltage would not change). With your thumb producing an increased resistance to flow but the current (rate of water to pass over time) not changing, you will get an increase in pressure (the hydro equivalent to electromotive force) causing the water to travel farther. When it comes to hydraulics, pressure is the result of a resistance to flow. Electrics operates slightly different.

Are you studying to be an electrician?

What is "load?" Does that refer to the needs of the appliance you are plugging in? What happens, does the appliance suck the electricity from the outlet like a baby from a bottle? I mean, does the appliance take it out of the wall, or does the electricity push its way like a garden hose? (I know this sounds like a weird question, but since electricity is likened to a "fluid" both images seem to come to mind.)

Does this mean that Tesla coils imitate what nature does with real lightning?

This post has been edited by Empress Palpatine on Dec 15 2007, 04:17 AM

Another thing....

I do not know if there is a clear way to describe it, but I was wondering about what it was so special Tesla did with the AC. The book about him that I am reading says that DC did not go very far and did not work well. AC is farther. When you said that word "phase" it reminded me of the word describing what he made. (Had no idea what that was). If phase is the wave, does that mean his had many waves? Polyphase?

Precursor562

Look, unlike you, I know and understand this stuff. I google nothing except some numbers and examples for you to read. Read the Tesla coil link I provided. I understand every thing in there. I've used the tools. I can do the analysis.

Nearly everything you are saying is totally wrong. I'm sorry, but that is the case.

We can take any statement you have made an prove it wrong (well, maybe there is something correct in that load of BS, but it will be hard to find)

Maybe you should wait until you finish your course (well, maybe 2 more years).

1. You don't understand Phases. You can't get 660V from 220 three phase. Your weasel words of 660V "effective" is not even correct. You need to study how three phase motors actually work. Maybe next year in school. But, I was correct about 2 phase (3 wire) 110/220 in a house. Maybe you can ask your teacher.

2. I won't argue with you about voltage and current. You have your single minded view. You may learn someday.

3. An 1800 watt hair dryer draws 16.4 amps from the 110 volt mains. PERIOD END OF STORY.
A 4000 watt dryer draws 9 amp from the 220V mains
It goes on and on. My house, at 1:30AM is drawing 1800 watts, according to my electric meter. No oven, stove, microwave, dryer, etc.

There is no 10A limit. You are wrong wrong wrong. 10 100 watt light bulbs draw nearly 10 amps

Show that to your teacher and he will laugh you out of the room. Please, do some googling. You are really off your rocker. Actually, I will do some for you:
http://en.wikipedia.org/wiki/3_phase_power

"The line-to-line voltage of a three-phase system is √3 times the line to neutral voltage."

(which means my 220 phase to phase, 110 phase to neutral was off, but try 120 V and 207V) Anyway, your description is out to lunch, I'm afraid.

Remember, though, that household wiring is 2 phase 110 (single phase 220) (actually, it is split phase, but I call it 2 phase).
http://en.wikipedia.org/wiki/Household_power

Hopefully you will learn something here. You obviously learned nothing in the 0.9r thread.

You are so so wrong. I can't believe it. I post links and you continue with your delusional BS. GO to ANY tesla coil page and read how they work. You are talking about a van de graaff generator.

http://en.wikipedia.org/wiki/Van_de_Graaff_generator

Here is a tesla coil, including a circuit diagram:
http://en.wikipedia.org/wiki/Tesla_coil

"A Tesla coil (also teslacoil) is a type of resonant transformer, named after its inventor, Nikola Tesla. Tesla coils consist of two, or sometimes three, coupled resonant electric circuits."

"An important characteristic of his later, higher power coil designs was that the primary and secondary circuits were also tuned so that they resonated at the same (high) frequency (typically, but not always, between 25 kHz and 2 MHz). "

You keep embarrassing yourself. I know what a tesla coil is. I can design tesla coils. I can analyze tesla coils. You have no idea what a tesla coil is, nor how it works. Follow the link I gave in a previous post. That stuff is easy.

You are delusional.
I will be happy to go to town with you on EMI and house hold wiring. Save it for the next post once you realize I know this stuff backwards and forwards, and you don't have a clue. This really is funny. A first year student spewing nonsense. Normally I would be slow and patient with such as your self, and help you along. but you just keep spewing.

Now you make it obvious that you cannot even understand the hydraulic model of electronics. There is no difference between your thumb increasing the pressure, and nozzling down to increase the pressure. Pressure is voltage.

Anyway, I know this stuff, and obviously you don't. You are only a first year student, so I would expect that. But, your wrong-headedness is astounding. I would be carefull about anything you post in response. Do yourself the favor of verifying it via google before you write it down. You have said many many totally wrong things that show you don't have a clue. I could list many more things from your post that are totally wrong.

This post has been edited by meBigGuy on Dec 15 2007, 09:22 AM

Has anyone here actually made a Tesla coil? (The making of these is practically a subculture). If you haven't yet, are you thinking of trying it?

Not me. I played with one in High School Science classes. I've never wanted to bother with winding and lacquring the transformer windings. Maybe it's time to build a monster?

Its easier to play with a microwave oven. There are lots of cool things you can do with that. My favorite (as I said before) is grape plasma. Just blows peoples minds (and the microwave, if you aren't careful)

http://www.barnesos.net/homepage/lpl/grapeplasma/

Check out this, too (I've never done it)

http://video.google.com/videoplay?docid=6732382807079775486

Lots of other microwave "science" links there.

Cool, but Tesla coils are so much more dramatic:

http://www.mgvolt.com/t-20spk5.htm

This "Eye of Sauron" is really cool:

http://tesladownunder.com/tesla_coil_spark...a%20of%20Sauron

The reason I ask is.....if you have made one you probably have extra insight as to what makes it work.

If someone in my neighborhood was to make one, I'd be curious to watch him make it. It would be interesting.

I know exactly what makes it work. It is based on transformers.

First I'll try to explain transformers in a simple way.

A transformer is a device that can increase/decrease the voltage of AC power in a very efficient way. You see transformers all the time. Those big round cans on utility poles are transformers. The little wall warts you plug into the wall to power things have transformers inside.

Basically a transformer is two or more coils wrapped around a common core such that the EM field from 1 coil is efficiently coupled to the other. What happens is that the power is "transformed" from the primary coil the the secondary coil. When that happens, it turns out the ratio of the number of turns of the two coils determines the ratio of the resultant voltage.

At this point you should probably read the wikipedia explanation also. Just look up transformer, and look at all the pictures.

So, we can couple coils inductively and change an AC voltage by the turns ratio. if the primary has 10 turns, and the secondary 100,000 turns, we will get a 10,000 to 1 increase in AC voltage.

When we increase the frequency of the AC, and run the transformer at resonance (tuned to be efficient) we can build fairly small highly efficient transformers to boost the voltage very high.

Big tesla coils (and Tesla himself, in his coils) use two transformers. The first transformer powers the high voltage spark gap system (15Kv or more) and the second creates the super high voltage. They use a spark gap to create high frequency discharges that are used to create the high voltage through the tuned resonant second transformer.

Here are some cool pictures of a monster coil that show all the parts.

http://www.teslacoil.net/sgtc/SGTC.htm

If you look at the flat coiled copper pipe, that is the primary of the second transformer. It has about 12 turns (looks like). Then look at the fine-wire vertical coil in the middle (secondary). Imagine how many turns it has. (it looks like a copper tube).

As you can see, this one runs off 240V and draw 20-30 amps. Would probably work at most homes. I don't happen to know what the secondary voltage of the pole-pig is.

Hope that helps, and feel free to ask more questions.

As I described earlier, your plasma balls work on the same principle. But, They don't use a spark gap to create the high frequency for the final transformer. (power and voltage levels are low enough they don't need to).