RE: Repost RE: Explain 3 Phase

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Tuite, Tom by way of Terry Fritz <twftesla-at-uswest-dot-net>" <TTuite-at-ALLEGROMICRO-dot-com>

Ah HA!!!!  Now I see where the confusion comes from!  Its not a phase issue
at all but one of hookup. This says it all:

> > Of course, I know where you are coming from, ie measuring V1 from
> > Ground to the top live, then V2 from the bottom live up to ground.
> > Yes, then the signals will appear to be in phase, but it's not
> > something you'll find most guys doing here.
> 
> 	They really would be best advised to understand, if
> 	contemplating a 240v hookup....

You see, if you hold two 3V batteries in your hand and put them in series
both facing in the same direction.  Then, if you take a DMM and read the
voltage from the - terminal of the first battery to the + terminal of the
second, you will get a 6V reading. So, you COULD say the battery voltages
are "in phase" (though really I would never say this).  If, now you took one
battery and flipped it around, and then took your DMM reading again, this
time from - terminal to - terminal, you would get a 0V reading and now you
could say the battery voltages are 180 degrees out of phase (ok silly
example, but hey it works :) ).  The same applies to the above mentioned
hook-ups.  Oooooooo and while I am posting, has any one here head of the
Hall effect?  I was wondering if any one has experimented with controling a
primary with a Hall effect swtich, hehe being an ultra newbie coiler I am
prob not the one to try :)    

Tom T.

> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Wednesday, May 02, 2001 10:00 PM
> To: tesla-at-pupman-dot-com
> Subject: Re: Repost RE: Explain 3 Phase
> 
> 
> Original poster: "davep by way of Terry Fritz 
> <twftesla-at-uswest-dot-net>" <davep-at-quik-dot-com>
> 
> Tesla list wrote:
> 
> > Original poster: "Alex Crow by way of Terry Fritz 
> <twftesla-at-uswest-dot-net>"
> > <alexcrow-at-blueyonder.co.uk>
>  
> > Yes, it is 180 degrees out.
> 
> 	Measured from the center tap, aka ground, indeed.
> 
> > Any *electronic* engineer
> 
> 	I am one.
> 
> > will tell you that the two lines are 180 out of phase. The ground
> > reference has *no effect* and can be ignored!
> 
> 	If its ignored, hooking up the scope will be interesting.
> 	If its ignored, measurements will be end to end.
> 	Which will show the whole to be In Phase.
> 
> > The waves are a mathematical function of time, but the "time"
> > axis actually represents the "angle" input to the trigonometric
> > functions.
> 
> 	Indeed.
> 
> > Eg the top wave could be represented as
>  
> > V1=sin(t)
> > 
> > and the bottom as
> > 
> > V2=sin(t+180)
> > 
> > if, of course, you are using degrees to calculate. Most 
> electronic texts use
> > radians by default.
> 
> 	OK, measured relative to the ground (center tap) is pi 
> radians...
> 	Measured end to end its zero radians/2 pi radians/in phase.
> 
> > The phase angle is unaffected by any static rail between
> > the lines.
> 
> 	But the measurement is...
> 
> > Of course, I know where you are coming from, ie measuring V1 from
> > Ground to the top live, then V2 from the bottom live up to ground.
> > Yes, then the signals will appear to be in phase, but it's not
> > something you'll find most guys doing here.
> 
> 	They really would be best advised to understand, if
> 	contemplating a 240v hookup....
> 	
> 	best
> 	dwp
> 
> 
>