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#### md11739

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Theory Question… We were hooking up a Buck-Boost trans on a 208v line 230v load circuit and one of my guys asked a question I couldn’t answer. If alternating current relies on the phases sin wave values alternating, does the length of the conductor changes the voltage difference between conductors? If A phase conductor is 80’ and B conductor 83’, does that difference in length throw off your voltage? We tried a few different cut lengths just to see if there would be a difference, and from what we could tell the answer is no. That’s intriguing; you would figure that it would. If you have 60 cycles per second and you have wire lengths that are different, you would think the voltage would be different. Any thoughts. Also, while testing voltage across the buck-boost, we were getting 230v between phases, however to ground was around 145v...?

#### piperunner

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Theory Question… We were hooking up a Buck-Boost trans on a 208v line 230v load circuit and one of my guys asked a question I couldn’t answer. If alternating current relies on the phases sin wave values alternating, does the length of the conductor changes the voltage difference between conductors? If A phase conductor is 80’ and B conductor 83’, does that difference in length throw off your voltage? We tried a few different cut lengths just to see if there would be a difference, and from what we could tell the answer is no. That’s intriguing; you would figure that it would. If you have 60 cycles per second and you have wire lengths that are different, you would think the voltage would be different. Any thoughts. Also, while testing voltage across the buck-boost, we were getting 230v between phases, however to ground was around 145v...?

Well I just run pipe all day but lets see at 60 cycles per second the human eye cant tell most digital meters give a summation of what is being tested average voltage reading so you cant tell . But if you want to get technical it does matter and there would be a drop or loss but its not that we need to see it being so minor in measuring voltage to conductor length it would change not the output but the final end voltage on your conductors .
My answer is yes it does but its effect is minor at your low frequency unless your above mega htz more copper resistance in your case .

#### brian john

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Two conductors of unequal length feeding the same load, the longer conductor will have a great voltage drop.

Run 75 feet and a 100 feet conductors and measure the voltage drop from the source to the load in each conductor, there will be a difference voltage in millivolts.

#### Mate

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It would take a lot more than 3 feet to see a difference.

#### brian john

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It would take a lot more than 3 feet to see a difference.
Longer would obviously would be better but as long as your meter has sufficient resolution you can measure the voltage drop.

Mate

#### Mate

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Longer would obviously would be better but as long as your meter has sufficient resolution you can measure the voltage drop.
Yeah I meant in V not mV

#### Ultrafault

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Good question. Electric potential travels at 174000 KMeters per second (speed of light x .58) In copper. So if you had a wire 2900 km long you would be one full sign wave off. Or you could get a wire, with no resistance, 725 km long and read a rms sign wave equal to the source voltage.

#### Mate

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Good question. Electric potential travels at 174000 KMeters per second (speed of light x .58) In copper. So if you had a wire 2900 km long you would be one full sign wave off. Or you could get a wire, with no resistance, 725 km long and read a rms sign wave equal to the source voltage.
:nerd:

#### Ultrafault

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#### drsparky

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Good question. Electric potential travels at 174000 KMeters per second (speed of light x .58) In copper. So if you had a wire 2900 km long you would be one full sign wave off. Or you could get a wire, with no resistance, 725 km long and read a rms sign wave equal to the source voltage.
Correct me if I wrong but I always though electricity move at near light speed.
Wavelength = velocity over time. A 60 Hz sign wave would be about 5000 km long or 3100 miles

#### wildleg

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Theory Question… We were hooking up a Buck-Boost trans on a 208v line 230v load circuit and one of my guys asked a question I couldn’t answer. If alternating current relies on the phases sin wave values alternating, does the length of the conductor changes the voltage difference between conductors? If A phase conductor is 80’ and B conductor 83’, does that difference in length throw off your voltage? We tried a few different cut lengths just to see if there would be a difference, and from what we could tell the answer is no. That’s intriguing; you would figure that it would. If you have 60 cycles per second and you have wire lengths that are different, you would think the voltage would be different. Any thoughts. Also, while testing voltage across the buck-boost, we were getting 230v between phases, however to ground was around 145v...?

while I don't agree exactly with Ultrafaults wavelength number, the key point is that at 60 hz the wavelength of the signal is so large that any difference in the length of wire by anything less than 50 or 60 miles isn't going to be measurable by your voltmeter.

#### wildleg

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Correct me if I wrong but I always though electricity move at near light speed.
Wavelength = velocity over time. A 60 Hz sign wave would be about 5000 km long or 3100 miles
v = c/f.

because the speed changes in a different medium (the copper wire), the wavelength changes from the vacuum speed you noted.

#### ablyss

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Theory Question… We were hooking up a Buck-Boost trans on a 208v line 230v load circuit and one of my guys asked a question I couldn’t answer. If alternating current relies on the phases sin wave values alternating, does the length of the conductor changes the voltage difference between conductors? If A phase conductor is 80’ and B conductor 83’, does that difference in length throw off your voltage? We tried a few different cut lengths just to see if there would be a difference, and from what we could tell the answer is no. That’s intriguing; you would figure that it would. If you have 60 cycles per second and you have wire lengths that are different, you would think the voltage would be different. Any thoughts. Also, while testing voltage across the buck-boost, we were getting 230v between phases, however to ground was around 145v...?

A sine waves maximum peak voltage(s) ( yes there are two ) are not determined by the length of a conductor but is directly related to the size of the magnetic flux and the speed the coil rotates around in the generator.
60Hz tells use the coil rotates 60 times in 1 second, independent of a conductors size.
Voltage drop however would increase as the length of the wire increases because the conductor has resistance. 3' is too short for any voltage drop. 100' ft then maybe you might notice 3 volts difference.

#### ablyss

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Good question. Electric potential travels at 174000 KMeters per second (speed of light x .58) In copper. So if you had a wire 2900 km long you would be one full sign wave off. Or you could get a wire, with no resistance, 725 km long and read a rms sign wave equal to the source voltage.
Voltage drop is a loss of electromagnetic force due to the increase in heat and other things like impedance. A phase imbalance or phase differences are a nutter ball game.

#### erics37

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Correct me if I wrong but I always though electricity move at near light speed.
Wavelength = velocity over time. A 60 Hz sign wave would be about 5000 km long or 3100 miles
Electricity is the transmission of electrons over a conductor due to induced potential. It is has nothing to do with electromagnetic radiation (like from the Sun) and does not travel at the speed of light. It is hindered by things like varying valence shells in conductive materials, temperature, etc

#### ablyss

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Electricity is the transmission of electrons over a conductor due to induced potential. It is has nothing to do with electromagnetic radiation (like from the Sun) and does not travel at the speed of light. It is hindered by things like varying valence shells in conductive materials, temperature, etc
An electron is a particle, along with neutrons and protons constitute the very fabric of atoms. So a particle is anything that does not have mass and in terms of what we can measure that is called the electromagnetic radiation spectrum. And yes electrical phenomenon falls in that category.

#### ablyss

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Correct me if I wrong but I always though electricity move at near light speed.
Wavelength = velocity over time. A 60 Hz sign wave would be about 5000 km long or 3100 miles
I've always wondered this too. If you think about electricity, it is just an electrical phenomenon based off what.... electromagnetic radiation . So, your comparing apples to apples. The speed of c in a vacuum doesn't change.

Alternating current is a complex manipulation of this phenomenon. And I mean complex in more ways than one, as complex numbers are used in sine wave analysis. A complex sine wave moves forward and backward in time. There really isn't any "movement" at great distances other than the total sum of all the applied electrons moving. Imagine a very long chain. The links represent the electrons. You pushing and tugging :whistling2: the chain back and fourth represents the voltage. To represent this as a time function a sine wave is used in both the real and imaginary domain, or as they say complex numbers.

#### brian john

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while I don't agree exactly with Ultrafaults wavelength number, the key point is that at 60 hz the wavelength of the signal is so large that any difference in the length of wire by anything less than 50 or 60 miles isn't going to be measurable by your voltmeter.
See Below

FROM Brian John Longer would obviously would be better but as long as your meter has sufficient resolution you can measure the voltage drop.
__________________

#### Tsmil

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ablyss said:
An electron is a particle, along with neutrons and protons constitute the very fabric of atoms. So a particle is anything that does not have mass and in terms of what we can measure that is called the electromagnetic radiation spectrum. And yes electrical phenomenon falls in that category.
No mass to an electron? I disagree. Long, long time ago, ( now I'm dating myself) we did an experiment in high school physics. We had a glass cylinder with cathode in one end and an anode in the other. There was a pinwheel in the centre. The cylinder was also under vacuum. When a charge was applied to the cathode and anode, the pinwheel would begin to spin. This was due to the travel of electrons from the cathode to anode hitting the pinwheel in its path. If electrons had no mass, it would not make the pinwheel spin. Oh, the pinwheel was not made of a ferrous metal. Although the mass of an electron is extremely small, it does have mass.

#### piperunner

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Well this is getting better each post just a little input a electron passing from one atom shell to the next does not move at the speed of light as we were schooled years ago . And the faster it moves depends on the voltage applied also the material its traveling in. It moves faster by increasing voltage and as voltage goes up the electron gets heavy is that mass or more energy what do you think ? It will never travel at the speed of light . It can get close but not in our electrical world not unless you have a 8 billion volt generac genset in your back yard .

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