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# Thread: Volts leaking to ground rod

1. Originally Posted by LLigetfa
Don, you have to be really fast. The polarity changes 60 times a second. Well... in some parts of the World at least. Not sure about in your alternate reality World.

I guess I need to get a faster meter.

In my alternate reality World we would use a O-Scope.

Have Fun.

2. Originally Posted by Reach4
When you measure voltage, it is with respect to a potential somewhere. If we are measuring with respect to the grounded center tap, the two hots are indeed 180 degrees out of phase with each other. Measuring WRT the grounded center tap is a most reasonable reference point.
Originally Posted by jwelectric
Pray tell us all just how the sine wave some how splits and inverts itself in a winding, it can't. There is no way possible that the winding can have a positive on both ends at the same time. Ever put batteries in a flashlight with one turned the wrong way? Didn't work did it? The same thing would happen if the winding some way ended up with a + at both ends
JW, are you agreeing or disagreeing with what Reach4 is saying? I can't tell

3. Transformers work using AC not DC. You will need to view the sine waves with an oscilloscope to see the changes.

4. Originally Posted by ankhseeker
Transformers work using AC not DC. You will need to view the sine waves with an oscilloscope to see the changes.

I figured I could just add a Rectumfier.

5. Originally Posted by ActionDave
This would not be unusual given the nature of our power grid.
I cannot say that the power guy was hysterical about it.

6. Originally Posted by Homeownerinburb
I cannot say that the power guy was hysterical about it.

Did anyone take Ground rod resistance measurements ?

7. Originally Posted by bluebinky
JW, are you agreeing or disagreeing with what Reach4 is saying? I can't tell
If you do away with the neutral then the secondary of the transformer would look just like the primary, one winding. When the positive arc in the sine wave enters the winding the winding becomes a magnet With a north and south pole as the sine wave returns to zero and enters the negative part if the sine wave the north and south of that electro magnet inverts. This happens 60 times a second which causes the winding of the secondary to do the very same thing. The center taps in no way changes this action taking place within the transformer.

Take two volt and half cells and connect them in series and spin it around at 60 revolutions per second letting the ends rub against two slip rings and you will have three volts AC at 60 Hz. Hold then in place and it will be three volts DC. Connect a three volt light to these two batteries connected in series and it will burn. Connect a 240 volt appliance across the secondary of the transformer and it will work.

With this three volt bulb burning a center tap of these two batteries and two 1.5 volt light bulbs can burn with one on one cell and the other on the other cell. All three are burning at one time.
Install a center tap on that secondary winding and two 120 volt appliances can be connect with one on one end and the other on the other end at the very same time the 240 volt appliance is in operation.

In order to have electrons flow there has to be a difference in potential or is you please a positive and a negative. If the two 120 volt sine waves were 180 degrees out of phase with each other this would mean that both ends of the winding would have to be positive at the same time and the center tap negative which would change 60 times a second. Also if they are 180 degrees out of phase the 240 volt appliance would not work.

Connect the scope channel A to one end of the secondary and the ground to the other end of the winding you would see one sine wave of about 340 volts peak or 240 volts RMS. Now move the ground to the center tap and a sine wave of only half of the winding or 120 volts RMS. When channel B is connected to the other end we get to see both ends of the winding at the same time, channel A in positive and channel B is negative which is in sync with each other not 180 degrees out of phase.

Using vector math we add the two together to come up with the single phase winding of the secondary. From the 120 volt reverence at both ends we have 240 volts. 120 from neutral to one end and 120 from neutral to the other end, is vector not degree of sine wave. We also use vector math when adding the two batteries, from the center tap to one end is 1.5 volts and from center to the other end we have 1.5 volts. This is the same as with the AC with the exception of the oscillation which AC has, or in other words while one end is positive the other end is negative.

8. JW, very good explanation which makes it clear you have perfect understanding of this subject. (not that any one ever doubted)

Originally Posted by jwelectric
... Connect the scope channel A to one end of the secondary and the ground to the other end of the winding you would see one sine wave of about 340 volts peak or 240 volts RMS. Now move the ground to the center tap and a sine wave of only half of the winding or 120 volts RMS. When channel B is connected to the other end we get to see both ends of the winding at the same time, channel A in positive and channel B is negative which is in sync with each other not 180 degrees out of phase. ...
However, (even though we're talking about a single-phase system) the correct terminology is that both hot legs are 180 degrees out of phase with respect to the neutral.

9. Originally Posted by DonL
I figured I could just add a Rectumfier.
Hey! I resemble that remark!

10. Originally Posted by DonL
Did anyone take Ground rod resistance measurements ?
Honestly, no, I don't own the gear. It is a few hundred dollars and I am inclined to assume that when I have a rod and copper pipe running horizontally for about 25', I should be good to go.

Two rods plus the copper pipe would certainly get the job done, certainly. But that is not what we have on hand.

11. Why do I get these duplicate posts?

12. Originally Posted by jwelectric
I
Connect the scope channel A to one end of the secondary and the ground to the other end of the winding you would see one sine wave of about 340 volts peak or 240 volts RMS. Now move the ground to the center tap and a sine wave of only half of the winding or 120 volts RMS. When channel B is connected to the other end we get to see both ends of the winding at the same time, channel A in positive and channel B is negative which is in sync with each other not 180 degrees out of phase.
Here is a picture of an oscilloscope with channel A being 180 degrees out of phase with channel B.

13. Originally Posted by jwelectric
Take two volt and half cells and connect them in series and spin it around at 60 revolutions per second letting the ends rub against two slip rings and you will have three volts AC at 60 Hz.

I cannot say that such an experiment has occurred to me, but it makes perfect sense.

Kind of off point, mind you....

14. Originally Posted by Homeownerinburb
Why do I get these duplicate posts?

When you get the message "Do you want to leave this page" after clicking Post Reply Click No, do not click Post Reply again.

That should put your post on the server.

Then close the page, you may get "Do you want to leave this page" again, Click Yes.

It works something like that but is hard for me to splain.

Good Luck.

15. Originally Posted by Reach4
Here is a picture of an oscilloscope with channel A being 180 degrees out of phase with channel B.
No they are not 180 degrees out of phase they are referenced from a mid point. There is no way they could be 180 degrees out of phase with each other as there is only one winding that has a center tap unless there has been something new invented that will somehow let one winding be 180 degrees away from itself.

What the scope is showing is a vector that is referenced from half way through a 240 bolt winding. As can be clearly seen is that while channel A is positive channel B is negative which means they are in phase not 180 degrees out of phase.
In order to be 180 degrees out of phase then both ends would have the same polarity.

Ever hear the old saying to believe nothing you hear and only half of what you see? Well that applies here until you take a course in vector math.

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