Re: basic questions

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Steve,

At 12:57 AM 8/15/2002 -0500, you wrote:
>Hello,
>
>I have some simple questions here.
>
>For a NST protection circuit, is it ok to use polyester(i believe) 
>capacitors, rather than ceramic??  I intend to at least have a simple LC 
>filter with at least the cap on each leg, and the resistors, along with my 
>safety gap.  I saw this simple filter on Gregs Garage, web site (i think).  
>The capacitors in question are Russian military caps rated 16kv 4700pf, id 
>use 2 in series for each cap.  I figure ceramic would be as bad as polyester 
>when it comes to RF.  Would these work??  Also, does anyone have any 
>suitable resistors that they may want to sell??  I dont have the money to 
>meet any companies minimum order, also why im not getting MOVs yet.

Any caps that can take the voltage will work.  Unlike MMC caps, there
really isn't anything special about filter caps.

>
>Also will power factor correction get rid of the problem of the lights 
>dimming in the house?!?  Im only running 1800VA transformer(2 15/60 NSTs).  
>I really dont understand why thats dimming the lights.  I heard some 
>arguements over PFC, in that its not really usefull.  So all i want to know 
>is, will PFC caps keep the lights from dimming?  will they really draw less 
>power/ cost less money to run my coil/ be able to run from a 15-20A switch?? 

With 300uF of PFC caps, you would probably cut the current to about 16
amps.  Probably close to 24 now.  You may be a bit cautiuous if your lights
dim a lot.  Might be bad wiring somewhere.

>  Also is it better to just be a little less than the calculated value for 
>PFC when in TC operation?  I heard the calculated value may be too much and 
>cause other problems, and that less than the calculated value will simply 
>not be 100% effective(but still very helpful).  Is this correct?  also what 
>voltage rating is needed for a 120v input?  Is 240v good enough?

For 2 15/60's about 300uF will be fine.  Could go to 400.  The caps can be
rated at 120 volts AC or higher.  They are sually higher.

>
>And one more!  Is it ok for me to be switching this much current with my 
>breaker switch.  I made a separate breaker box for my coil, with a 15A 
>breaker in it.  I have been using this as a switch, with out the use of a 
>relay.  Is this ok for a ~20A+ load?  I know that if i go any higher i will 
>be pushing my luck, but am i already?

The breaker switch is fine.  They are built super tough.  They normally can
switch fault currents of thousands of amps when needed.

>
>Thanks for all the help this list has provided.  Its taken my coiling to the 
>next level of quality and understanding.

No problem :-)

Cheers,

	Terry


>
>Steve Ward.
>
>