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#126916 - 03/10/01 05:25 AM An analogy of Electrical Power transfer  
Scott35  Offline

Broom Pusher and
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA
This message is to elaborate a little more on parts of the "how does electricity flow" thread - more specifically, it's to expand on Sparky66wv's question about Energy Transfer [does voltage get used up?] and somewhat amplifies on dturner's response on using water pipes and their pressures as a model for Voltages.

In this example, I will be using simple closed fluid systems, using water for the hydraulic fluid.
This should [hopefully] explain the way power is transfered from the generating device, to the load using electrical circuitry.

The primary thing that is being done with any electrical circuit is to transfer energy from point A to point B. Point A would be the generating device, point B would be the load. The conductors and related components are the path for the energy to "flow" through.

A simple example of a complete system would be a Battery, Conductors and a DC electric motor [let's say it's a fan motor].

The Battery, which is where the energy is derived from, is a Transducing device that converts Chemical Energy into Electrical Energy [Electrons under pressure]. The load, which is the electric fan, is a Transducing device that converts Electrical Energy into Mechanical Energy [the spinning fan blade].
The Conductors are nothing more than a pathway between the Battery and the Motor, and the Electrical Current - under pressure - is nothing more than an electrical version of the power [energy] that the Battery supplies and the Motor receives, plus developes.

Electrical circuitry is a very convenient method of transferring energy from one point to another. It can be run in much easier ways than using another method - or medium - to transfer the energy.
The energy required by the load device [what ever item is doing work] will need to be supplied by the device supplying the energy.

A simple and basic law of energy is that it cannot be created from scratch [that's almost impossible across the universe], nor can it be destroyed, or used up. It will only change from one state to another.
The most common state of energy is Potential Energy [AKA Static Energy, can also be thought of as matter with 100% Static Inertia]. This is energy laying around at rest - doing nothing more than taking up space [Linked Image]
The other state of energy is Kinetic Energy [AKA Dynamic Energy, can also be thought of as matter containing some static and some dynamic Inertia]. This is energy that is moving, or actually doing something [most of the time it's in the form of heat energy].

I'm sure that everyone has seen, or heard of Einstein's famous Theory: E=MC2 - but not everyone understands it's meaning.

The equation simply states this: E=Energy [in this case, Kinetic Energy], M= Matter [in this case, Potential Energy], C= Speed of light, in a vacuum [in this case, 300,000 KM per second at -0kp - or less than 0 atmosphere].

The Matter, is any piece of physical matter that is available. It is not figured in any Molecular or Mole fashion, but in an Atomic fashion. So for simplicity, think of M as an Electron [a free Electron in larger elements] from a certain element [atom].

When the M is sitting still, there is no E, but when it's moving, there is E.

This Theory is how ElectroMagnetic Radiation works [Electricity, Radio, Light, Etc] and is also a basic for Atomic Reactions [except they either lose some M {fission} or gain some M {fusion} after the event - that releases E - too far off topic to discuss here plus way too difficult to explain using text!!].

As I stated, energy cannot be created, nor destroyed, so how does a battery, generator, or whatever create power and what happens to everything after it goes through the load device??
It might seem very difficult, but it's not - as long as you remember the stuff I mentioned above. The future end of all the energy that gets dissipated in electrical devices changes at somepoint into heat [some form of Infrared Light], which then becomes static once again through heat conduction. When the complete area that involves the place where the heat is transferring to colder parts, making everything one stable tempature, it's now back to Potential Energy [this is known as "Ground State"]. What ever gets heated in the transfer [air, dirt, walls, your arms, etc.] will continue to transfer heat to the colder place, until there is no more heat to transfer.
Some knowledge of thermodynamics is helpful, but not totally necessary if you can grasp those simple things.

Now for a sample system!! {finally [Linked Image]]

In this example, we will be using liquid water in a closed system [pipes, etc.] to turn a hydraulic fan, which will be powered by a hand pump [a crank attached to a centrifugal pump].

The pump is designed so that positive pressure is flowing upwards, return from underneath. We will use PVC pipe to connect the hydraulic fan motor to the pump, with the pipes running horizontally. 90 degree elbows connect the pipes to the pump and motor and are as close to their ends as possible [90 right out of the pump and motor].
The fan blade attached to the motor will move 10 CFM at 100 RPMs. We'll say this requires a net input of 1 horsepower, just to keep the numbers simple and in full units. We'll neglect the Joules and Calories required and stick with the 1 HP figure.

If I want to move the 10 CFMs of air with the fan, I will need to Induce a level of energy into the water, through the pump, that equals the required 1 HP. I received a bulk amount of Potential Energy from eating green veggies and tasty fruits! The plants that grew these items received energy from the Sun in the form of Kinetic Energy, then they stored it inside themselves in Potential Energy form. I will use this to Induce Kinetic Energy into the fan.

When I spin the pump, I create a level of Pressure on the Water Molecules that are in the Pump. This, in turn, reacts on the remaining water inside the pipes, and eventually on the water in the fan motor.

The Pressure I have created [which makes the water move] can be thought of as Voltage [EMF], and since there is a closed circuit with opposite levels of Potential [a difference in Potential, or a difference in pressure], the water can flow.
The water can be thought of as the Current that is flowing [or available Amperes].
The combination of the water [Amperes] under a certain pressure [Voltage] results in an energy being transfered into the motor, then transduced [changed into] mechanical movement of the fan and the air being pushed by the fan. This energy can be thought of as the Power, in Watts, that the motor requires.

All the Kinetic energy that is being carried by the water gets induced into the fan motor. We'll ignore Voltage Drop and other losses and say this is an ideal system.
FYI: The Voltage Drop can be thought of as the way water would be "slowed down" when it flowes through pipes with real rough internal surfaces.

I will need to turn the pump at the speed needed to produce the 1 HP at the fan. The speed of the pump determines the amount of energy I can put into the water, which will be transfered to the fan motor.

So what happens with the water after the energy is transfered to the motor? It flows back to the pump, due to the Negative pressure [or Vacuum] that is created by the "Supply" side of the pump when it's being turned. Along with that, the water behind it "Pushes" it away. This is like the way Electrons Repel each other.

The supply side kind of creates little "Holes" in the water, that the water naturally wants to fill. This is similar to the Positive Charge flow transfer in the opposite direction of the Electron flow.

To make this an AC system, simply replace the Centrifugal pump with one that has 2 pistons. Set the pistons 180 degrees [rotation] from each other, so that one is fully down when the other is fully up. Connect the pistons to a crankshaft [like a typical gasoline motor] and the hand crank to the flywheel end of the crankshaft. This will convert the turning motion from me into reciprocating [back and forth] motion for the pistons.

Now when I turn the crank, the water flows in one direction, then stops when one piston reaches the top, then the water flows in the other direction from the 2nd piston pushing it. Which ever direction the water first began flowing in will determine the direction the fan motor will turn.

Even though the water has reversed it's flow direction, the motor continues to turn the same direction [we'll say this motor also has a heavy flywheel on it and the points where the water enters and leaves the motor are not directly above each other - they are offset from each other with respect to the impeller].

This message is WAY too long, so I'll cut it here.
If possible, I'll add some more stuff on the energy thing.

Also, if there's a part you don't quite understand [more like which parts], let me know and I'll reply with a BRIEF explaination [Linked Image]

Hope you guys like this one!

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

Tools for Electricians:

#126917 - 03/10/01 08:01 AM Re: An analogy of Electrical Power transfer  
Scott35  Offline

Broom Pusher and
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA
Boy I can sure ramble on, huh!! [Linked Image]

I sure hope you guys don't get irritated by these long messages, just have not yet figured out a way to cut the size without cutting the info.

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#126918 - 03/10/01 08:02 AM Re: An analogy of Electrical Power transfer  
sparky  Offline
Joined: Oct 2000
Posts: 5,303
interesting reading Scott !

[Linked Image]

#126919 - 03/10/01 08:03 AM Re: An analogy of Electrical Power transfer  
sparky  Offline
Joined: Oct 2000
Posts: 5,303
that's ok, the anologies are easy to visulize and follow

[Linked Image]

[This message has been edited by sparky (edited 03-10-2001).]

#126920 - 03/10/01 09:49 AM Re: An analogy of Electrical Power transfer  
Scott35  Offline

Broom Pusher and
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA

Thank you for the input! So glad that you could understand what the heck I was trying to explain!

As stated, it was to amplify more on the stuff in the first thread from this discussion area [the "how electricity flows" thread].

Now if everyone else is able to "Decode" [Linked Image] this message and understand it as well, we might possibly have succeeded in explaining a wide variety of electrical stuff!!

If we don't succeed, then a Watermelon will help - guaranteed to "Suck Seed" there [Linked Image]
[just a joke!!].

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#126921 - 03/10/01 10:54 PM Re: An analogy of Electrical Power transfer  
sparky66wv  Offline
Joined: Nov 2000
Posts: 2,236
West Virginia
Thanks Scott..

Yes, Please keep up the "elaborate" posts...I'm learning more since I've been a member of this forum than I did in all my apprentice years...

Residential/Commercial Inspector
5 Star Inspections
Member IAEI

#126922 - 09/20/03 04:17 AM Re: An analogy of Electrical Power transfer  
james S  Offline
Joined: May 2003
Posts: 107
West England
great anology scott sure is a good idea looking at thing from diffrent angles!
its been a while since visiting the forum due to computer problems/holidays things like that.

just one part of your message that i dont grasp!

when you say that after all heat has been used up and returns back to a potential energy (ground state), is it possible to use this energy again in the same way, the way im thinking is that you can no longer do anything with the ground state energy so in effect the energy is used up?

ps i aint trying to prove Einstein's theory wrong here, i simply dont get it YET. [Linked Image]

#126923 - 09/20/03 08:15 PM Re: An analogy of Electrical Power transfer  
Scott35  Offline

Broom Pusher and
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA
WOW!!! I haven't seen this topic for SOOOOOOO long!!! Had forgotten all about it, too!

Man, this was written a long time ago! 2001! Look at how far things have come here at ECN!

Anyhow, to answer your Q'; If the matter is at "Ground State" it still possesses the same energy - just all in a static state. To get something Kinetic / Dynamic from it, there must be a difference in energy levels.


Boulder rolls down a hill, then stops. it stays at the same place for eons, until an earthquake comes along - which cracks the ground directly underneath the Boulder.
Now the Boulder falls into the crack until an opposing force stops it once again (that force would be the Boulder getting stuck in the crack, or hitting the bottom of the crack). Boulder remains here for eons again, until something else happens, which creates a similar situation.

Boulder's actual "zero potential / ground state" place would be the center of the Earth's core (or where ever the highest concentration of Gravitrons exists). That's the Boulder's attractive force, in a basic sense [Linked Image]


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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