220V dryer sparked on startup (3 wire) What to test?

Page 11 of 16  
On Sunday, November 17, 2013 5:57:38 PM UTC-5, snipped-for-privacy@attt.bizz wrote:

Of course you didn't respond. The few responses you give are typically one word, like "wrong" or some sarcastic remark that ignores the issue.
Where's your response to this, from an electrical eqpt manufacturer?
http://www.behlman.com/applications/AC%20basics.pdf
In describing 240/120V split phase they say:
"The two legs, represented by Phase A and Phase B are 180 deg apart."
Exactly what the poster said that you claim is impossible, wrong, stupid, etc.
Or how about this. Are you familiar with the IEEE? The Institute of Electrical and Electronic Engineers? Are they a respected peer reviewed group or also just a bunch of idiots? From one of their conference papers on power systems, which was published and presented at a conference:
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber4520128
"Distribution engineers have treated the standard "singlephase" distributio n transformer connection as single phase because from the primary side of t he transformer these connections are single phase and in the case of standa rd rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Whi ch now brings into focus the reality that standard 120/240 secondary system s are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. "
It couldn't be any clearer. The author of that IEEE paper says "they are *not* really single phase systems, instead they are 3 wire system s with two phases".
Bingo! Exactly what I've said. And now you have it from an IEEE conference paper on electrical distribution systems. Read it and learn.

If you spent half as much time learning as you do with the attacks, you might have some hope.
Remember when everyone was an idiot who told you that you were wrong when you claimed it was illegal for an employer to help pay for Obamacare for their employees? Or how about the time you made an ass of yourself, with me, Bud, RBM, trying to explain to you that you didn't know what you were talking about with regard to a 4 wire vs 3 wire appliance connection? Just like those, here you are. With no references, just your arrogant, ignorant, flapping gums. Well congratulations, you've just done it again.

ase distribution system. It is the AC equivalent of the original Edison thr ee-wire direct current system. Its primary advantage is that it saves condu ctor material over a single-ended single-phase system while only requiring single phase on the supply side of the distribution transformer.[1] The two halves are 180 degrees apart with respect to center point."

Oh, I see. "opposite" is the precise term according to you. While 180 deg phase difference is slang. Go figure.

I can read and I'm sure everyone following the thread can too. They know you've once again made a complete ass of yourself. The IEEE paper proves it. But I know you'll just say that's wrong too. BTW, where are YOUR references?
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On Sun, 17 Nov 2013 16:11:53 -0800 (PST), " snipped-for-privacy@optonline.net"

Idiot. I've responded *MANY* times. You keep saying *exactly* the same thing in different ways and expect a different, wrong, answer. Sorry, but you may have nothing else to do in your life but argue, I'm done playing your game. If you haven't been able to read what I've written by now, I'm not wasting any more time on you.
As an engineer, you certainly suck.
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On Sunday, November 17, 2013 9:17:27 PM UTC-5, snipped-for-privacy@attt.bizz wrote:

Then the IEEE, the most respected electrical engineering organization in the country, must suck too, because here's a paper from the IEEE that specifically addresses the exact issue:
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber4520128
"Distribution engineers have treated the standard "singlephase" distributio n transformer connection as single phase because from the primary side of t he transformer these connections are single phase and in the case of standa rd rural distribution single phase line to ground. However, with the advent of detailed circuit modeling we are beginning to see distribution modeling and analysis being accomplished past the transformer to the secondary. Whi ch now brings into focus the reality that standard 120/240 secondary system s are not single phase line to ground systems, instead they are three wire systems with two phases and one ground wires. Further, the standard 120/240 secondary is different from the two phase primary system in that the secon dary phases are separated by 180 degrees instead of three phases separated by 120 degrees. What all of this means is that analysis software and method s must now deal with an electrical system requiring a different set of algo rithms than those used to model and analyze the primary system. This paper will describe the modeling and analysis of the single-phase center tap tran sformer serving 120 Volt and 240 Volt single-phase loads from a three-wire secondary."
Here's the essential point that says I'm right and you're wrong. I've seperated it out for you, since you clearly have a learning problem:
"Which now brings into focus the reality that standard 120/240 secondary sy stems are not single phase line to ground systems, instead they are three w ire systems with two phases and one ground wires."
That's from a paper published by the peer reviewed IEEE and delivered at a conference of power engineers. Read it and try to learn something instead of hurling insults.
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On 11-17-2013, 21:17, snipped-for-privacy@attt.bizz wrote:> Idiot. I've responded*MANY* times. You keep saying*exactly* the > same thing in different ways and expect a different, wrong, answer.
Indeed. You should have learned two dozen posts back tht you'll just keep getting the same wrong answer.
> Sorry, but you may have nothing else to do in your life but argue, I'm
Oh, the irony....
--
Wes Groleau

You always have time for what you do first.
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On 11/19/2013 2:12 AM, Wes Groleau wrote:

Have you noticed that some Usenet posters repeatedly say that they won't answer any more?
--
.
Christopher A. Young
Learn about Jesus
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> >

Hi, In summary between L1 and L2(240V) there is no phase to talk about. Between L1 and CT, L2 and CT(2 x 120V ) there is phase to talk about. If it were single phase one, this two legs will have alternating output. I had to dig out my old school text book. And I had to drag out my Tek. dual trace scope in a LONG time. Nothing to difficult to understand, really!
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Mark Lloyd wrote:

Hmmm, Let's refresh trigonometry from HS, draw the AC wave form on a piece of paper(one full sine wave, 1 Hertz), what phase means or related term leading or lagging by such and such degrees. L1 leg represent top half of sine wave and L2 bottom half. So how many degrees apart between L1 and L2? For convenience we can say that L1 is positive half and L2 is negative half or vice versa..
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snipped-for-privacy@attt.bizz wrote:

Hi, Draw the wiring out to visualize, it is just one winding with center tap!
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two-phase and split phase are different. Reference previous link to two-phase
http://en.wikipedia.org/wiki/Split-phase_electric_power
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On Sat, 16 Nov 2013 17:53:52 -0700, Tony Hwang wrote:

BTW, this is a picture of my incoming mains (my power comes from underground).
http://farm3.staticflickr.com/2886/10915925156_0e21cf1404_o.gif
Does that picture tell us anything about the neutral with respect to the ground?
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No.
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On 11/16/13 11:09 AM, snipped-for-privacy@attt.bizz wrote:

Most pivot irrigation system run off 3ø 480VAC. We sometimes tap power off the supply for the grain bins. Those are typically 1ø?? 240 VAC like the supply for dryers. We add a step up transformer and a phase converter to make the pivots run. Does that alter your thinking?
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240 off of a 480 system? How did you manage that? It should be 277.
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On 11/18/13 10:40 AM, Nightcrawler® wrote:

I didn't explain that very well. The supply is 240 single phase at the bin sites. We kick it up to 480 and add a phase converter for the third leg to power the pivots.
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No, it is single phase, or split phase. Only one phase is used and is center tapped to split the voltage. It is impossible for this circuit to be out of phase with itself.
Bi, or to be more precise, two-phase, is a rare entity that is primarily used in military applications, specifically in aviation. My old Air Force generator had the ability to provide two-phase, and pretty much anything else that you wanted from selection of voltage to three-phase delta or wye.
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On Sat, 16 Nov 2013 13:51:46 -0600, Nightcrawler®

+1
One leg is the opposite of the other by the very nature of the transformer.

Precisely. It starts with the two phases in quadrature (90 degrees) and a transformer to generate any desired phase relationship.
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On Saturday, November 16, 2013 6:07:17 PM UTC-5, snipped-for-privacy@attt.bizz wrote:

ees

No one is claiming anything is out of phase with itself. The simple statement was made that one of the hot legs of a 240V dryer is out of phase with the other by 180 degrees. Look at them on a scope, what do you see? Phase in this context is just the relationship of one waveform to another. Two waveforms can differ in phase from 0 to 360 deg. With a sine wave, when one differs from the other by 180 deg, they can also be said to be the opposite of each other.

Correct. And when you have one sine wave that is the opposite of the other, it's a 180 deg phase difference. Look at it on a scope or graph it. It doesn't matter how exactly the waveform difference is generated.
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Re-read what I wrote, and what you and others are trying to assert. Think really hard about it. The secondary of a residential transformer only has "one" winding. It is fluxed by "one" winding. Meaning that it is not a poly-phase system Hence, no phase shift. How the primary winding is powered varies, and just might use two phases of a three phase system, yet since there is only one secondary winding, the secondary winding only has one phase angle. Zero offset between the hot legs and the center tap for there is only one winding and either side of the center tap is at the same phase angle as the other.
To kill two birds with one stone.
In the utility world, the term "phase" references one leg (output) of a poly-phase system. This does not matter if the transformer is delta or wye. I would say the same thing about generators, but you would be hard pressed to find a three-phase delta generator. (trying to get a ground reference is a pain in the ass and cost a a lot more money). The three outputs are called A, B, and C. There is more about delta systems, but that does not pertain to this conversation.
Around here, Arkansas, they supply the primary with one hot and a neutral. In the Bay Area, Ca, the primary uses two hots. Not necessarily poly-phase in origin, but the closer you are to commercial buildings, and such, the greater the chance that this is the case.
Regardless, a three phase wye generator and/or transformer is the only true power source on the grid that has a "neutral". Something you will not see around your meter-main, ever (unless you are very lucky :-)).
I could go on, but another football game started...
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On Saturday, November 16, 2013 8:29:52 PM UTC-5, Nightcrawler® wrote:

I have thought hard about it and I'm fully aware of the meaning of the term phase.
The secondary of a

Hook up a dual input oscilloscope to hot 1 and neutral and hot 2 and neutral at the dryer. Show that plot to a school student and ask:
"What is the phase relationship between waveform A and B?"
What's your answer?
How the primary winding is powered

Each side of the secondary is 180 deg opposite the other. It is referred to as "split-phase", right? When you split a something, do you still have just one?
Here:
Split-phase electric power
http://en.wikipedia.org/wiki/Split-phase_electric_power
"A split-phase electricity distribution system is a three-wire single-phase distribution system. It is the AC equivalent of the original Edison three- wire direct current system. Its primary advantage is that it saves conducto r material over a single-ended single-phase system while only requiring sin gle phase on the supply side of the distribution transformer.[1] The two ha lves are 180 degrees apart with respect to center point. "
Note the very important last sentence. That is all I and Mark Loyd and others are saying.

Yes, but the utility world doesn't own the term phase. It's widely used to describe the relationship between two or more waveforms in math, physics, electrical engineering. And in the broadest sense, in any of those fields, it's simply the relationship between two or more waveforms. Exactly how they got generated doesn't matter. If you can hook up a scope and see two different waveforms and one is 180 deg out of phase with the other, then that is the relationship, is it not? And two sine waves differing by 180 degrees is what you get from a center tap transformer delivering 240/120.
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snipped-for-privacy@optonline.net wrote:

Hi, Of course in radio wave dealing with E and M field, in acoustics dealing with sound wave, in hydraulics dealing with liquids, gases, etc. Doppler effect in radio wave or sound wave, light wave, etc., etc. Also not all waves are sine waves.
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