[Prev][Next][Index][Thread]
Re: flat strip primary
Hi Bob, Sam, all,
SNIPola
>Original Poster: "Samuel Rosset" <samr-at-chez-dot-com>
>If I'm right, you want to use your strip your your PRIMARY right???
>Well, you don't need to worry about the spacing between turns. Electricity
>wont jump from one to another, because the difference of potential between
>turns is very low (copper is a good conductor). A primary is not a cap.
>between the plates of your cap, you have a difference of potential of 9KV
>(even more in fact), that's why you have to be concern about distance
>between the plates.
>So you don't have to worry about electricity jumping between turns.
>Nevertheless, spacing is important, for it will determine the inductance
>(and therefore frequency) of your primary. Use Ed Sonderman's spread sheet
>to design the "perfect" primary for your secondary...
Sam, there are two things you didnīt consider:
1.) The strap has sharp edges, which might lead to corona, interturn arcing
or enhance secondary to primary arcs.
2.) The primary acts like an autotransformer. Example:
Primary has 10 turns. You tap it at 5 turns. The 9kV are now across
5 turns. The voltage from turn zero to turn ten will be 2*9kV = 18kV!
2a.) Furthermore, the voltage between turns depends on the number of
total turns the input voltage lies across.
Example:
5 turn Primary (9kv across it): Volts per Turn = 9/5 = 1.8kV
10 turn primary (9kv across it): Volts per Turn = 9/10 = 900 volts.
Depending on design, the volts per turn in the primary may become
critical (Low Fres = low number of turns and a big cap).
Coiler greets from germany,
Reinhard