Volts leaking to ground rod

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DonL

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Where is a moderator when you need one ?

We are confusing the OPs original questions with basic electric law. But is a good place to start.


Is this a test ?
 

JWelectric

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From post :105: Are you saying that you won't answer if point A in phase or out of phase with point B? Seems like a simple question. It is not a complex question.
I am saying that it has nothing to do with what we are discussing but if you need an answer what you have posted is two independent 120 volt systems assuming that the device they are attached to are NEMA devices. They are the same signal, they are both 120 volt and 240 volt cannot be derived from them.
They are neither in phase or out of phase with each other they are independent.

Just what are you trying to prove with this nonsense? I have a door bell transformer and so does my neighbor are they in phase or out of phase?

Answer this, a delta center tap 240 volt transformer has how many phases? A wye center tap transformer has how many phases? Either is a three phase system unless we believe the hogwash you are selling in which case the delta is a 5 phase, three for each leg and two for the center tap and the wye has 9 phases three at 208 and six for the center tap.

I think I will go to the supply house and tell them I need a 240 volt 5 phase panel for my delta system or even better yet a nine phase for my wye system. I sure hope they don’t have a heart attack laughing at me so hard.

A short lesson in Basic Electricity 101, The word phase is defined as; a particular appearance or state in a regularly recurring cycle of changes as defined by Webster.
In the world of electrical talk it is the angle of a sinusoidal function such as one phase is 120 degrees out of phase with the next phase in the series. As we look at the sine waves we can see that they are 120 degrees out with each other but what we don’t see is that one half of the sine wave is 180 degrees out of phase with the other half of the sine wave.

What you are doing is trying your damnest to show that one 240 volt sine wave is indeed two separate phases that are 180 degrees out of phase or that the positive and negative of a battery is 180 degrees out of phase with each other.

I am beginning to wonder if you have yet grasped the fact that there has to be a positive and a negative in order to have current to flow. Two cells in series with a center tap will show up on a scope as two different signals so now it is your turn to answer a simple question, it is not a complex question. Are those two batteries 180 degrees out of phase with each other?
 

DonL

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I have a 12 Volt battery.

What would the RMS voltage of this battery be if I use a true RMS reading meter ?


Are we having fun yet ?
 

Jadnashua

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I have a 12 Volt battery.

What would the RMS voltage of this battery be if I use a true RMS reading meter ?


Are we having fun yet ?

You're not really helping anyone with comments like this...
 

Reach4

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I am saying that it has nothing to do with what we are discussing but if you need an answer what you have posted is two independent 120 volt systems assuming that the device they are attached to are NEMA devices. They are the same signal, they are both 120 volt and 240 volt cannot be derived from them.
They are neither in phase or out of phase with each other they are independent.
Thank you for responding. Of course the rest of us think they are clearly in phase.
Just what are you trying to prove with this nonsense? I have a door bell transformer and so does my neighbor are they in phase or out of phase?
Back on post 50... you were taking strong issue with a web page saying that the two hots of a center tapped distribution transformer were out of phase. You were wrong in saying they were in phase. Two signals being in phase or out of phase has nothing to do with what power company phase is powering the circuit.
Answer this, a delta center tap 240 volt transformer has how many phases? A wye center tap transformer has how many phases? Either is a three phase system unless we believe the hogwash you are selling in which case the delta is a 5 phase, three for each leg and two for the center tap and the wye has 9 phases three at 208 and six for the center tap.
Three phases, but that doesn't mean that an AC circuit phase cannot produce AC that can be in phase or our of phase. "In phase" or out of phase are just the most simple of phasing. Are the current and voltage on a power factor correction capacitor in phase? No. The current leads the voltage by about 90 degrees. But wait... that capacitor is hooked to a single phase. Yep. That is the way it works.
I think I will go to the supply house and tell them I need a 240 volt 5 phase panel for my delta system or even better yet a nine phase for my wye system. I sure hope they don’t have a heart attack laughing at me so hard.
Yeah, about as hard as a plumbing supplier would laugh if you were to ask for a 10 gpm or a 60 PSI pipe. A house may be piped with a single water pipe, but that does not mean there cannot be different pressures in the house.
A short lesson in Basic Electricity 101, The word phase is defined as; a particular appearance or state in a regularly recurring cycle of changes as defined by Webster.
In the world of electrical talk it is the angle of a sinusoidal function such as one phase is 120 degrees out of phase with the next phase in the series. As we look at the sine waves we can see that they are 120 degrees out with each other but what we don’t see is that one half of the sine wave is 180 degrees out of phase with the other half of the sine wave.
One half of the sine wave? I don't know what you are trying to describe with that term.
What you are doing is trying your damnest to show that one 240 volt sine wave is indeed two separate phases that are 180 degrees out of phase or that the positive and negative of a battery is 180 degrees out of phase with each other.
You were the one who started the battery analogy on this thread. Batteries have polarity. AC has phase. Yes, you can make an analogy, but it is only an analogy.

Two separate phases? No. Not separate. Two different voltages. Same frequency. Out of phase with each other-- which does not mean they are powered by a different phase of 3-phase power.
I am beginning to wonder if you have yet grasped the fact that there has to be a positive and a negative in order to have current to flow. Two cells in series with a center tap will show up on a scope as two different signals so now it is your turn to answer a simple question, it is not a complex question. Are those two batteries 180 degrees out of phase with each other?
Those non-commoned battery terminals have opposite polarity with respect to our reference.

http://en.wikipedia.org/wiki/In_phase has some discussions of "in phase" etc.

If you only recognize "phase" as identifying which piece of a 3-phase and you cannot agree that the term "out of phase" or "in phase" can apply to voltages in a circuit powered by a single transformer, well, you are missing out.
 

JWelectric

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Thank you for responding. Of course the rest of us think they are clearly in phase.
Back on post 50... you were taking strong issue with a web page saying that the two hots of a center tapped distribution transformer were out of phase. You were wrong in saying they were in phase. Two signals being in phase or out of phase has nothing to do with what power company phase is powering the circuit.
Three phases, but that doesn't mean that an AC circuit phase cannot produce AC that can be in phase or our of phase. "In phase" or out of phase are just the most simple of phasing. Are the current and voltage on a power factor correction capacitor in phase? No. The current leads the voltage by about 90 degrees. But wait... that capacitor is hooked to a single phase. Yep. That is the way it works.
Yeah, about as hard as a plumbing supplier would laugh if you were to ask for a 10 gpm or a 60 PSI pipe. A house may be piped with a single water pipe, but that does not mean there cannot be different pressures in the house.
One half of the sine wave? I don't know what you are trying to describe with that term.
You were the one who started the battery analogy on this thread. Batteries have polarity. AC has phase. Yes, you can make an analogy, but it is only an analogy.

Two separate phases? No. Not separate. Two different voltages. Same frequency. Out of phase with each other-- which does not mean they are powered by a different phase of 3-phase power.

Those non-commoned battery terminals have opposite polarity with respect to our reference.

http://en.wikipedia.org/wiki/In_phase has some discussions of "in phase" etc.

If you only recognize "phase" as identifying which piece of a 3-phase and you cannot agree that the term "out of phase" or "in phase" can apply to voltages in a circuit powered by a single transformer, well, you are missing out.

Way back when I started in the trade we used a lot of ice cube relays for what now is done with PLC. One of the first trick l learned was to take the coil of a magnetic starter, insert my screwdriver, energize the coil and remove the screwdriver while it is still energized would de-magnetize it and not accidently close or open contacts while working on the system. Stick it in and energize it for just a second would magnetize it to hold screws.

As the sine wave of the primary starts from zero and climbs to a peak in the positive half of the sine wave the core of the transformer aligns its atoms with a north and south magnetic field. As the voltage drops from a peak positive to zero again the magnetic field of the core goes away. Then the sine wave leaves zero and climbs to a peak negative causing the poles of magnetism to change directions.

The magnetic field induced into the core of the transformer by the primary is induced into the secondary winding. Now here is a treat for you. The voltage produced by this induction will be 180 degrees out of the primary voltage. What supplies our homes will be a two winding transformer, one primary and one secondary. This can be seen in the video link I posted of how a transformer is made. The turn ratio of the transformer will depend on the primary voltage.

Taking a scope and connecting it to the middle so both ends of the winding can be seen at the same time does not make two voltages that are 180 degrees out of phase. What we see on the scope is the winding on both ends at the same time. Channel A will be showing us the positive half of the sine and channel B will be showing us the negative half at the very exact same time.

Should we set the scope to show just one sine wave on the screen we would be looking at 1/60 of a second in time. Those grids across the screen will be in the very same time frame vertical and this is where you think that they are out of phase.
As the sine wave started on the left of the screen we would be seeing both ends of the winding starting its climb to a peak, we would see the positive at the same time we would see the negative.

But then again why am I talking the time to explain this to someone who don’t understand what half of a sine wave is, I do hope you know that an AC sine wave will have a positive and negative.

In induction the voltage will lead the current and in capacitor the current will lead the voltage by 90 degrees. Capacitor banks are used to clean up the power factor of factories that has a lot of induction such as motors and transformers.
 

Reach4

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Taking a scope and connecting it to the middle so both ends of the winding can be seen at the same time does not make two voltages that are 180 degrees out of phase. What we see on the scope is the winding on both ends at the same time. Channel A will be showing us the positive half of the sine and channel B will be showing us the negative half at the very exact same time.
This is the heart of our disagreement on terminology. The center tapped secondary makes the two voltages out of phase, and connecting the oscilloscope as you describe will show two sine wave 180 degrees out of phase. There is a voltage as A. There is a voltage at B. However they got there, they are out of phase.
Should we set the scope to show just one sine wave on the screen we would be looking at 1/60 of a second in time. Those grids across the screen will be in the very same time frame vertical and this is where you think that they are out of phase.
As the sine wave started on the left of the screen we would be seeing both ends of the winding starting its climb to a peak, we would see the positive at the same time we would see the negative.

But then again why am I talking the time to explain this to someone who don’t understand what half of a sine wave is, I do hope you know that an AC sine wave will have a positive and negative.
"Half of a sine wave" is not a common term. To somebody thinks the voltages on opposing ends of a center-tapped secondary are in phase, who knew what "half of a sine wave" might mean.

I see a sine wave as a continual thing -- not just a 16.67 ms piece. A 16.67 ms piece is a single cycle of a 60 Hz sine wave. The time between peaks or troughs is the period of the wavelength.

We all know how basic AC waves and transformers work. Our disagreement is whether the two ends of a center-tapped transformer or the two hot buses in a common breaker box are out of phase with each other. I say yes. You say no. I think voltages at points A and B in the schematic on post #106 are in phase. You kinda implied that that "in phase" or "out of phase" would not even apply to voltages A and B in that schematic.
 
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Bluebinky

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I have a 12 Volt battery.

What would the RMS voltage of this battery be if I use a true RMS reading meter ?


Are we having fun yet ?

Very easy to answer. 12V DC is 12V RMS by definition. What would be interesting is to see JW do the math for calcualting RMS on a sinewave (or even write down the equation).
 

Reach4

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If he does, you could refer to him as or jωt rather than JW. :)
 

Bluebinky

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What you are doing is trying your damnest to show that one 240 volt sine wave is indeed two separate phases that are 180 degrees out of phase or that the positive and negative of a battery is 180 degrees out of phase with each other.
No, not quite.

What I am saying is that in order to have a developed voltage between two wires (terminals) you need a difference in potential between them.

In the case of DC we often call the terminals + and -. This is usually sloppily done without reference to anything.
If you put two batteries together +-+-, and then measure the voltage of both ends from the center, you will indeed get + on one end, and - on the other. The two terminals are of opposite polarity according to the way we just measured.
On the other hand, if you measure from the - end, the center terminal will measure +, and the far terminal will be 2x +. Oh no, one of the batteries is now broken, because it now has plus terminal and a plusser terminal. Now measure from the + end and the other battery is broken -- how can that be? Jeez...

Phase is a mathematical term for the time relationship between two conductors of when each terminal reaches a certain point in its cycle. That number will change depending on how you make the measurement -- just like the DC example with polarity -- you will get different phase relationships, depending on where you place your "common lead" when measuring the output of a center tapped transformer. There is no "mystery physics" involved -- just common accepted terminology which aligns with the accepted mathematical model.

There is a unique property of a sinewave -- shifting 180 degrees is the same as inverting the polarity. This is intimately intertwined mathematically with a straight line in geometry -- which is indistinguishable from a 180 degree angle... Notice I did not say two lines. With three points, you either get one line or three between them.

Saying that you can understand phase from "Electricity 101" is sort of like saying you can understand the NEC by reading Wikipedia.

About 20 years ago, I had an argument with my PhD boss who claimed that you could measure the phase relationship between a continuous 60 MHz reference sinewave and 60 Mhz pulses that came at 10 Hz by taking digitized samples at 4 Mhz (particle bunches in a linear accelerator). But, I opened my mind and did the math. It worked. I was able to design and build an interface board using relatively cheap off the shelf parts, and implement his "goofy math" in software.

BTW, JW, you are obviously a smart guy with way more experience in what you do than I would have if I lived 300 years. I appreciate what I have learned form you in the last couple of years. Thanks.
 
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Jadnashua

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In an a/c circuit...the current is moving either one way or the other, and in our power infrastructure, it alternates at 60Hz, passing through a zero point as it stops before going the other way in a sinusoidal waveform. The point is, from one side of the secondary to the other, it can only be flowing one direction at a time - IOW, BOTH ends of the secondary MUST be rising or falling in unison. A/c doesn't need what we think of as ground, but we use one for safety purposes in our power, which can confuse a picture when, say, you try to look at it with an oscilloscope. On a secondary of a distribution transformer, both ends are rising or falling at the same time, therefore they have to be in sync. What's driving that condition is the primary, which again, doesn't care about ground. The current FLOW may go clockwise around the leg with A, and counter-clockwise around B's during one half cycle, and reverses on the other half, but on the neutral those two currents since they're flowing in opposite direction, they cancel out. If the two ends of the secondary were opposites, when using something running on 240vac, they'd be butting heads and there would be NO current, just like the current on the neutral balances out - if they could both be flowing in opposite directions, instead of the current in the neutral cancelling, it would DOUBLE, and that doesn't happen.

Sometimes, what we picture in our mind to try to make sense of things, leads to incorrect assumptions, and is just plain wrong.
 
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Meanwhile, does anyone have an opinion as to which way the current was flowing on that ground line?

Keeping in mind that the flow continued at the same level when the main breaker to the house was turned off.
 

Houptee

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Did you check if there was a non NEC required bonding jumper across the hot and cold pipes at the water heater?

If so put a clamp on ammeter on that jumper. Any current reading?

Go to cold water pipe coming from the street any current?

If yes, proceed to re-pipe house with PEX starting from the meter in the street.

Sound like fun?
 

ActionDave

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Meanwhile, does anyone have an opinion as to which way the current was flowing on that ground line?

Keeping in mind that the flow continued at the same level when the main breaker to the house was turned off.
Seven tenths of an amp on the earth ground is nothing in the real world.
 

JWelectric

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This is the heart of our disagreement on terminology. The center tapped secondary makes the two voltages out of phase, and connecting the oscilloscope as you describe will show two sine wave 180 degrees out of phase. There is a voltage as A. There is a voltage at B. However they got there, they are out of phase.
If you would slow down just a little and use that gray matter resting between your ears you would realize that what you are seeing on that scope is two different connections to one winding from opposite ends at the very same time. It is the connection that is 180 degrees out not the signal you are seeing.
Think of it as being able to stand under both goal post and look at the 50 yard line at once.
Goal post A and goal post B looking at 50 yard line C in no way makes the football field 180 degrees out of phase.
"Half of a sine wave" is not a common term. To somebody thinks the voltages on opposing ends of a center-tapped secondary are in phase, who knew what "half of a sine wave" might mean.
I suppose that half wave rectifiers are a figment of my imagination and something that is not very common although they are used every day of our lives

I see a sine wave as a continual thing -- not just a 16.67 ms piece. A 16.67 ms piece is a single cycle of a 60 Hz sine wave. The time between peaks or troughs is the period of the wavelength.
this might be part of the problem

We all know how basic AC waves and transformers work. Our disagreement is whether the two ends of a center-tapped transformer or the two hot buses in a common breaker box are out of phase with each other. I say yes. You say no.
How can a single phase be out of phase? If there is only one present it would be sort of hard to make it out of phase with itself. Now just what kind of panel is it? A 240 volt single phase panel not a two phase 120 volt panel

I think voltages at points A and B in the schematic on post #106 are in phase. You kinda implied that that "in phase" or "out of phase" would not even apply to voltages A and B in that schematic.
What that is a picture of is one primary with two secondary that are completely separate. They are neither out nor in phase with each other. Tell us just how you would achieve 240 volts from them.
 

JWelectric

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I have a 208/240 to 24 volt transformer that was taken out of an air handler. This transformer is installed so that either 208 or 240 can supply the air handler and still have 24 volts to the thermostat.

Now know that a transformer does no care which side voltage is applied it will still produce voltage to the other side. If 24 volts were applied to the secondary there would be a dual voltage on the primary of 208 and 240.

Would the transformer produce two voltages of 208 and 32 volts that were 180 degrees out of phase? No! it would produce the two voltages and they would be in phase with each other.
 
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