Re: [TCML] PFC Question (again)--more

[FutureT@xxxxxxx]

In a message dated 5/27/2008 4:22:54 P.M. US Eastern Standard Time,  
FutureT@xxxxxxx writes:

>David,

>I didn't do the calcs lately but I think it's  close to  resonant,
>maybe slightly LTR.  He's running at 120  bps.  At 120  bps,
>you pretty much have to use resonant or  LTR to get good 
>power throughput.   

>John


Also (adding to my posting here).  Resonant and LTR have  a
different meaning for pig and PT coils than for NST coils.  
For an NST coil the resonant sized cap or LTR value cap is
a certain value.  For a pig or PT coil, the setting of the  ballast
determines if the coil operates in STR, resonant, or LTR  mode.
At the pig or PT's rated power, there may be a particular  value
cap for LTR or resonant.  But such a coil can be run at  more
or less than it's rated power.  For example at 120 bps, a  small cap could be
installed on a pig coil, a certain amount of ballast can be  cranked
in to make it resonant, and it will run, but at less than  the
transformer's rated power.  For example let's say the  resonant
value is 0.3uf.  A cap of only 0.03 can be installed, and the  correct
amount of ballast can be cranked in to give resonant  operation,
and the coil will run.  It won't draw much power, and sparks  will
be short, but it will be running in resonant mode.  Also an  "LTR"
value cap can be installed on the pig coil, and the needed  ballast
can be cranked in to give resonant operation.  Perhaps  the
transformer will draw twice it's rated power, but it will still be
able to operate in resonant mode, despite having an "LTR" value
cap.  Sparks will be very long in this case.  In any case  resonant
operation depends a lot on the ballast setting for pig and PT  coils,
unlike for NST coils which have a fixed leakage inductance,  and
a fixed resonant cap value.  If a pig or PT coil is run with a  small
cap at high bps, then the ballast L has to be reduced to let  in
more power (if long sparks are desired).  Then the coil is  truly
running in STR mode.
 
John









**************Get trade secrets for amazing burgers. Watch "Cooking with 
Tyler Florence" on AOL Food.      
(http://food.aol.com/tyler-florence?video=4&?NCID=aolfod00030000000002)
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla