Re: phase help

In a message dated 99-10-28 06:25:35 EDT, you write:

> when you talk about phase, like " its not in phase" or that is a 
> "three phase transformer"    what does that mean??
 _ >>


Phase refers to two or more things being in time with each other.
For instance if the current and voltage are in phase, then if you
observe the waveforms on an oscilloscope, one will line up with the
other, (you can adjust the traces vertically so that one will exactly
overlap the other).  If they are out of phase with each other, then
one waveform will appear to lead or lag the other, they will not 
overlap exactly on a scope.  The distance between the zero crossing
points of each waveform will remain constant however, and will have
a different distance if the phase is becomes different. 

  signal A             ^ ^ ^ ^ ^ ^             ^ ^ ^ ^ ^ ^          ^     ^   
 ^    ^
  signal B             ^ ^ ^ ^ ^ ^              ^ ^ ^ ^ ^             ^     ^ 
   ^    ^  
                          in phase            out of phase        out of phase

The ascii diagram above gives some idea of phase conditions but 
the ascii is not very good.

Phase is a relative measurement....one thing timed relative to another.

John Freau