Relating Voltage, Etc.. To Hertz?

I'm a layman when it comes to anything physics related so you can imagine someone like me would be having a hell of a time figuring out how to gauge energy produced via electricity without training. I'm most confused about correlating volts to electron volts or volts to hertz. The latter is my primary interest, but I'm pretty sure I'm going about the whole thing wrong, so I wonder if anybody here can clear some things up for me. For one, I've been seeing through web searches that you can have different voltages tied to the same frequency. Confusing. O_o Even though I'm a noob, I was positive only a specific voltage would be associated with a specific frequency. Sucks to be me since that wasn't the case (crazy to assume when you don't know, but I often do).

Anywho, I haven't been this confused trying to figure out something since I took up server side programming some years back. Any help anyone can forward is appreciated here (any help that doesn't involve me having to pursue becoming an electrician to understand that is).

Thanks.

The easiest way I can think of to explaining it is like this.

A/C voltage stands for alternating current. Meaning the voltage alternates between +&- to produce current.

The United States runs on 60HZ. Unless specifically specified wich is rare. Europe runs on 50 HZ.

Whether you are dealing with standard 120 volt outlets, 240 volt, 480, 600,1600,ect..... all voltages are running at 60 HZ. doesn't matter if it's single phase or three phase.

When you stare at lit light bulb. That light bulb turns itself on and off 60 times in one second. Obviously so fast you can't even notice it. Now in Europe where they run at 50 HZ people that are used to a 60HZ system can sometimes actually notice a difference. Not in brightness necissarily, although that is a contributing factor to getting a brighter light. But they actually can see a flicker. The oscilation in the wave.

You can get desired voltages by running through a step-up or step-down transformer. Some times known as buck and boost transformers.

Frequency can be achieved through frequency drives or alot of other crazy solid state stuff that costs a fortune to the regular "joe".
A cheap way of getting high frequencies is to build a Tesla Coil and other online science projects.

I hope this is helpfull. If you don't mind me asking. What are you playing with?

reply to post by massexodus


Good questions. I will try to answer as best as I can.

#

First, let me talk about electrical power. Power is voltage, multiplied by current. For example, if you have 100 Volts and 7 amps, you end up with 700 Watts (100 X 7 = 700), which is about one horse power.

So you see, in order for you to understand electrical power, it requires understanding of TWO different aspects of electricity: voltage and amperage. Voltage is force, like water pressure. Amperage is the flow of electrons, like how many gallons per second are flowing out of a water tap.

#

Now, regarding Hertz: here is one of the truly amazing things about voltage and current -- you can switch the direction of current very quickly -- first it is flowing one direction, then the other. There is no loss of power to make this happen. (Maybe a very small bit, due to resistance, but we will ignore that.)

You can have 10,000 volts applying pressure in one direction, and then in a millisecond, it flips over and applies pressure in the other direction. It is no big deal for this to occur 60 times a second (60 Hertz) or 20,000 times a second (20,000 Hertz)

That may seem strange in a world where momentum prevents a car from slamming immediately into reverse, at the same speed it was traveling forward at a millisecond before. But that is what is cool about electricity. It can change directions on a dime!

The important thing to note: Hertz is just a measurement of frequency, and does not have any bearing on understanding power, which is just voltage times amperage.

#

So finally, you mentioned energy. Power is different from energy, but many people confuse that. Energy is just work. Work and energy are pretty much synonymous.

Power is different -- it is actually the RATE at which work is done, not the work itself. If you want to make something happen, you need energy. To make it happen FAST you need to increase the POWER.

So, back to voltage -- to make those electrons move faster, you increase the voltage. That causes the current to go up, and the power to increase. You can also increase the power by reducing the load (resistance). Reduce the load on a fixed voltage, and the current and power will increase.

#

This is all off the top of my head. By the end of my unior year, studying electrical engineering in college, I still found all of this very confusing. Now that I have it figured out, I feel a bit compelled to try to explain it, hence the length of this post.

What are you trying to do, Mass? Sounds like you have a project going on.

Originally posted by highfreq
The easiest way I can think of to explaining it is like this.
I hope this is helpfull. If you don't mind me asking. What are you playing with?

Cool stuff High Freq. Amazing how similar our posts started and ended. I promise you I didn't see that coming.

We must be on the same frequency. (That would be about 10 Hz in my case.)

Think about a puddle of water. You throw a rock into the middle of the puddle, and it makes waves spread out in a circle. Frequency is how many waves pass by some point in the water in a certain amount of time, say one minute. The voltage is like how high the waves get from one extreme to the other. Obvuiously, although both measurements are concerning the same wave, they concern different aspects of the wave, so they are not dependent on each other. You could have a very high fast wave, a very high slow wave, etc.

The connection of eV to volts is a little more complex, but suffice it to say it's similar. eV are units of charge, while voltage is a unit of electrical 'pressure'.

Hope this helps, and I'm curious too.

TheRedneck

Hey Massexodus,

Hertz is the frequency of an AC signal. Think of a sine wave, frequency is the amount of times a signal completes one full cycle from zero to positive to zero to negative and back to positive again. Hertz is measured in cycles per second. Voltage is represented by the amplitude of the signal. Again think of a sign wave evenly split with a line running from right to left. The line represents zero volts. the top of the wave above the zero volt line is the positive voltage and the peak of the wave below the zero volt line is the negative voltage. This is just a simplification, the sine wave it self is a representation of voltage over time. As the wave rises above the line voltage becomes more positive, as the wave dips below the line voltage becomes more negative.
Hope that helps.

reply to post by Buck Division


ya' that's pretty far out...I have to admit though I like your response better

Are you a sparky as well?

If I'm following correctly.. you guys are telling me the same frequency can be maintained, no matter the power involved, since they are technically separate. This does make sense to me. So it's also similar to turning on a water hose and aiming it in reverse direction at an interval with my arm. No matter how hard I have the water going (power) as long as my arm rate of directional change stays the same, I'm still working at the same frequency. Is that it?

The connection of eV to volts is a little more complex, but suffice it to say it's similar. eV are units of charge, while voltage is a unit of electrical 'pressure'.

Oh, please do break it down for my simple mind.

Frequency can be achieved through frequency drives or alot of other crazy solid state stuff that costs a fortune to the regular "joe".

Frequency drives? Solid state stuff? More info please.

P.S.

I'm not working on any project btw. I feel it's in my best interest to understand how all of this works before going forward with anything. Safety first. I don't want to go the reckless route, dive in, play with electricity, and die from a 2 foot spark because I was a dumb ass that didn't know how much juice the jug was carrying (if you know what I mean) and I became the fun pole to ground. Just trying to get all the basics down.

The frequency of an AC voltage is only a factor in that it determines the reactance of capacitive and inductive elements in the circuit making things more complex for AC circuits than DC where resistance is the deciding factor in overall impedance (AC resistance if you like).

You might have seen the term RMS (Root of the Mean of Squares) applied to AC voltages. 240V RMS will produce the same heating effect on a purely resistive load over time (I^2.R.T) as 240V DC although the AC 240V has peaks of +/- 340V approximately if it's a sine wave.

Also remember that an AC waveform need not necessarily pass through zero (zero being the 'ground' or zero potential reference point). If I built a solid state sine wave oscillator and amplified its output up to, say, 12V RMS and applied that voltage to the secondary of a 240/12V transformer I'd have a mains inverter with 240V RMS appearing on the transformer primary winding terminals. Relative ground references can be manipulated in endless ways with a little ingenuity.

I think you will find it all here.



en.wikipedia.org...

Hope this helps

Mungo

reply to post by massexodus

The connection of eV to volts is a little more complex, but suffice it to say it's similar. eV are units of charge, while voltage is a unit of electrical 'pressure'.

Oh, please do break it down for my simple mind.

If you want complete understanding, there is no way I can fully explain it here. The post length is simply too short, and I don't have that much time, to be perfectly honest. I'd suggest a good search of wikipedia, as mungodave suggested, or even better, get a good physics textbook. You can grab one for a reasonable price from the local college bookstore (I recommend a used book) or Amazon, or simply ask one of the physics professors which book they recommend. It's not unheard of to have someone give you a basic book that they have had for years, although I wouldn't recommend asking for that right up front, obviously.

I commend you; the search for knowledge is a fabulous journey. Good luck, and watch out for those 2-foot sparks.

TheRedneck

Any electrical measurement can be explained by a water analogy.

Volts = PSI which is pressure.

Amps = amount of gallons delivered.

Ohms = resistance which is analogous to skin friction in the pipe which will slow down water flow.


Frequency, known nowadays as Hertz is well explained in several of the above posts.

Frequency used to be known as cycles, but somewhere along the line it became known as Hertz to honor a physicist named Heinrich Hertz.

Volt, ampere, ohm and a host of other electrical researchers and scientists are named after people who did experimenting and research in the field when it was in its infancy.



A key thing to remember about frequency; frequency remains the same at any voltage on a particular system and all generators have to operate at the same electrical speed when tied to a system or large grid.

Meaning that the 36 pole machines at Hoover Dam can run in electrical synchronism with an 18 pole machine elsewhere.

Physically, Hoover dam generators run at 200 rpm and the 18 pole machine runs at 400 rpm.

Frequency on a large electrical system like the Western United States grid varies by only a few thousandths of a cycle over the course of a day.
As long as there are no major problems the frequency remains balanced due to generaton is regulated against load.

That means, generation and load are exactly the same.
Change either side of the equation and the frequency will vary.

(Edited for spelling.)

[edit on 28-3-2008 by Desert Dawg]

[edit on 28-3-2008 by Desert Dawg]

If I'm following correctly.. you guys are telling me the same frequency can be maintained, no matter the power involved, since they are technically separate.

Well....Yes and No. That is assuming you are taping into the electrical grid supplied by your local power company. Now if you are talking about generating your own power via magnetic induction, no. The best example I can give would be the old PTO generators. Before hooking up any load you should check the frequency with a meter. In the instance of a PTO generator or most generators for that matter, Hertz is proportional to RPM's. Meaning the faster the RPM's the greater the Hertz, and vice versa.

Frequency drives? Solid state stuff? More info please.

Frequency Drives are sometimes known as Variable Speed Drives....I better source this one for you.

AC variable speed drives operate on the principle that the synchronous speed of an AC induction motor is directly proportional to the frequency of the AC power supplied to the motor. The inverter section of the drive consists of solid state switching devices that reconstruct an AC power signal with controlled frequency. The three most common types of inverters are variable voltage source (also called six step), current source and pulse width modulated (PWM). The six step inverter uses six solid state switching devices in combination with six diodes. The solid state switches are controlled to produce a six step voltage wave form for each phase. Changing the conducting time for each of the six switches results in a change in frequency of the output wave. The current source inverter operates much the same as the six step variable voltage source except that solid state switching devices construct a six step current wave for each phase instead of a voltage wave. Pulse width modulated inverters use solid state switching devices to produce a series of constant voltage pulses of various widths to produce an AC output. The timing and number of pulses are varied to produce the varying frequency.

SOURCE

If you are looking to produce really high frequencies the best advice I can give you is to build a Tesla coil. Though you may have to run the load side voltages through some external electronics to get the desired voltages and frequencies, such as transformers(which by the way is kinda what a Tesla coil is any way), rectifiers, diodes and a bunch of other cool stuff that I really don't want to confuse you with.

The problem I am having here is I suck at teaching As stated above, sometimes the best way to really understand this stuff is to read a book.

For me, without really knowing what your desired outcome or application is I find it a little more difficult to maybe give you a good answer.

Hope you recieved the information you were looking for.

If you want to learn about AC electricity, you should start with DC or direct current and start with Ohm's Law. Once you get a feel for that, the same laws apply to AC alternating current. Hertz is the unit for frequency which is how fast the AC cycles through the sine wave. Voltage is the amplitude of the sine wave or the peak value of the waveform.

It sounds to me though that you may be working with a voltage step up switching power supply or a boost converter. The faster you switch or the higher frequency it is, the higher the voltage output that is generated. This is similar to how a Tesla coil gets the high voltage to arc across the air. This is pretty advanced and dangerous. I don't recommend messing with it if you don't know what your doing.

Me too, I wouldn't start playing if you don't know what you're doing.

A couple of points. Firstly to get a variable frequency you need an inverter that you can vary the output frequency. These usually are MOSFET or IGBT driven, as in variable speed drives as mentioned earlier.

Secondly voltage & Hertz isn't really a measurement that you'd use. Sometimes you might use current x Hertz, for example if you were using transducers, in order to work out the magnetic saturation of the core.

Maybe if you could give a few clues as to what you're doing one of the nice gents above might be able to help you more. I can't, I hate electronics & have just left the industry after 15 years to work for myself

Originally posted by massexodus
I'm most confused about correlating volts to electron volts or volts to hertz.

I was positive only a specific voltage would be associated with a specific frequency.

There is no correlating volts to hertz. Voltage is the difference of electrical potential between two points of an electrical or electronic circuit.

An electron volt (symbol eV) is a unit of energy. It is the amount of energy equivalent to that gained by a single unbound electron when it is accelerated through an electrostatic potential difference of one volt, in vacuo. In other words, it is equal to one volt (1 volt = 1 joule per coulomb) multiplied by the (unsigned) charge of a single electron.

Hertz is the measure of the frequency of occilation in an AC circuit (how many times the dirrection of the flow changes, per minute) 50 Hz.= 50 changes in dirrection per minute. 60 Hz.= 60 changes per minute. etc...

As you see one has nothing to do with the other.

Hope this helps.

Originally posted by massexodus
Any help anyone can forward is appreciated here (any help that doesn't involve me having to pursue becoming an electrician to understand that is).

Thanks.

Watch out the last person that I remember asking detailed questions about electricity on here decided to pursue an Associates Degree in Electrical Engineering

Originally posted by TheRedneck

If you want complete understanding, there is no way I can fully explain it here. The post length is simply too short, and I don't have that much time, to be perfectly honest. I'd suggest a good search of wikipedia, as mungodave suggested, or even better, get a good physics textbook. You can grab one for a reasonable price from the local college bookstore (I recommend a used book) or Amazon, or simply ask one of the physics professors which book they recommend. It's not unheard of to have someone give you a basic book that they have had for years, although I wouldn't recommend asking for that right up front, obviously.

I commend you; the search for knowledge is a fabulous journey. Good luck, and watch out for those 2-foot sparks.

TheRedneck

I agree entirely especially the part about watching out for those 2 foot sparks

Massexodus the best books that I have found for someone wanting to learn about electricity and electronics is the Navy Electricity & Electronics Training Series (NEETS)... They start you out at the basics and go from there in a very well planned step by step process that is easy for anyone to understand. You can download them for free here


[edit on 31-3-2008 by Heckman]

reply to post by Heckman

Ooooh, thank you! I had no idea they were downloadable.

I used to have a few of these and yes, they are excellent books. Several times I have wished I still had them (I gave them to a young man interested in learning electronics years ago) to refresh my knowledge from time to time.

If the military does anything well other than killing people and breaking things (their job, of course), it is writing thorough manuals and textbooks.

TheRedneck

reply to post by ParaShredder



hi im new and need some help in some technical aspects from someone who understands electricity extensivly
i cant post yet but maybe you can help heres my question and understanding from what ive read
hz is a frequency that tells cycles per second
the human body gives off beta theta and aplha waves that can be measured in hz
the question i wana understand is the human body gives off energy obviously measured in hz but no one seems to know what type of energy it can be turned, transfered or amplified into how to bring the hz into a viable energy that could potentially become amplified into either lets say voltage then amplify it or contain capture etc i feel this is very plausable it can be measured that a human can produce more than other humans if you train youreself to do it up to 4 times the normal volume measured on an osciliscope why cant that be used and turned into a viable electricity that could lets say charge a battery
what is human energy considered to be
what would attract this energy
what would a person need to amplify the output
oh one other question what is the part of the brain called that is on the right rear lower side just above the spinal colum or their in that can conduct electrical activity

reply to post by stephanies


I'd have to say that all energy within the body is for utilization by the body with excess input being stored in chemical form (fat) as an emergency reserve. Most of the energy derived from food intake is used for simply maintaining body temperature as is the case for all mammals and other warm-blooded creatures. The idea of extracting that energy for external uses sounds dangerous (for the host's survival prospects) and efficiency would be much better if the food's energy was extracted without using a living host.

All parts of the brain and central nervous system use electrical impulses to control muscles and sensory nerves send electrical signals back to the CPU (the brain) for processing. The part of the brain you referred to is, I believe, the medulla oblongata (could be wrong there) and it takes care of autonomic functions like heartbeat, breathing, digestive system etc etc IE all the things that keep you alive without you necessarily needing conscious control over them.