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Re: Still Oops...




>Original Poster: RWB355-at-aol-dot-com=20
>
> Original Poster: "A.C. Kuntz" <bigvolts-at-hotmail-dot-com>=20
>
>Hello A.C.
>You wrote:=20
>" It does not matter what else is inthe circuit, if the 0.5 resistor 
has
>50ampRMS flowing through it, it will get 1250watts!! this is a bad  
desig=
>n. A
>properly designed inductor should just work, you dont see  commercial
>florescent light ballast or NST with resistors in them!!"
>
>Ehmmm, not quite. If I use a 0.5 ohm resistor AND a 6kVA (-at- 240v e.g.)
>inductive ballast in series for example. The total current that will 
flow=
> is
>going to be less than 25 A, so the current flowing thru the resistor 
HAS =
>GOT
>TO BE less than 25A. Simply because the inductive ballast will limit it 
t=
>o
>that current.

Oh, thats a good way to reduce the resistor losses, just make a lower 
power coil!!  you know, if you use a 1kVa ballast insted of 6kVA or 
10kVA to limit current to 4.2A, then the resistor losses are even lower, 
only 9watts!! Who wants a 10kvA coil anyhow??

>The reason why a FL light or a NS doesn=B4t use a resistive/inductive 
bal=
>last is
>quite simple:=20
>First of all they don=B4t care about slight fluctuations and what=B4s 
mor=
>e
>important a FL light or a neon sign is a continues load once started. 
So =
>your
>current won=B4t be continuesly jumping around.
>
>A spark gap isn=B4t a continues load!!

Actually the real reason that nobody would buy a resistive ballast is 
its too inefficient.  Would you choose resistive ballast for your big 
office bldg lights just because resistors are cheaper than inductors??

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