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Re: Mid-point Ground

Since center tapped xformers have been one of the mysteries of electronics
for me, you've drawn me into the fray.  This is getting dangerous since I think
I understand you.  

To put this in applied terms:
- If you have a long run of GTO to the ends of the tubes, tie the long runs to the
center tap and to ground.  Then split the circuit in half and tie each end, where
you split it, to one of the high tension leads. The long runs are then at zero 
volts  potential to the world around them.
Many potential (no pun intended) problems can be avoided.  However I think
you need to make sure it is a good ground, not a floating one, correct?

- If you don't have the problem of long runs, leave the center tap unconnected
since it won't gain you anything. Correct?
But you could use the split circuit idea anyhow, if you had some local code
restriction or another reason to reduce the voltage used.
Are there any good reasons for reducing the voltage?  Reduced EMI comes to
mind.

- What about the case where you might want to use the transformer in an unbalanced
situation?  Two cases come to mind
   1.  The difference is small and probably unintentional, like the 50 volt differential
mentioned in an earlier post.  Tie it to ground anyhow?  I thought the NEC
had some unkind words about intentionally applying voltage to ground.  I know
from expereince that it can cause all sorts of problems if the ground is,
or becomes, a floating ground shared with other things.
  2. Intent\onal and major unbalanced - for example only using one side of
a center tapped transformer since it was too big for the circuit.  Just how
much of a problem is this?

Thanks for the information.

P.S. You both drew the same picture - exactly the same.  Somewhere between
our screens is a server that chops up the lines, inserting EOLs.  Also it
looked like one
of you (Tom) was using a fixed space font and Kenny was using a proportional
spaced one.  ASCII art never works.  I've even had my own artwork cc'd
back to me and it was garbbled.

Neonewbie,

-------------------------------------
Roger D. Smith, Neonewbie
unaffiliated with infoserv
All my opinions are opinions, to be sure.