Re: Surge / Ground / Lightning

On May 5, 2:20=A0pm, phil-news-nos...@[EMAIL PROTECTED]
 wrote:
> In alt.engineering.electrical trad...@[EMAIL PROTECTED]
 wrote:
>
> | On May 5, 1:44?am, phil-news-nos...@[EMAIL PROTECTED]
 wrote:
> |> In alt.tv.tech.hdtv bud-- <remove.budn...@[EMAIL PROTECTED]
> wrote:|
phil-news-no=
s...@[EMAIL PROTECTED]
 wrote:
> |>
> |> |> In alt.engineering.electrical Leonard Caillouet <nos...@[EMAIL PROTECTED]
>
w=
rote:|> | <phil-news-nos...@[EMAIL PROTECTED]
> wrote in message
> |>
> |> |> |news:fvjhvk016vr@[EMAIL PROTECTED]
> |> |> |> In alt.tv.tech.hdtv Franc Zabkar <fzab...@[EMAIL PROTECTED]
>
wrot=
e:
> |> |> |
> |> |> |>
> |> |> |> The MOVs will act like conductors when they are clamping. ?The
su=
rge will
> |> |> |> take both paths ... the path through the MOVs, and the path
going=
 past the
> |> |> |> MOVs. ?In general, about 50% will go each way. ?That can vary
at =
higher
> |> |> |> frequencies.
> |> |> |
> |> |> | Why would you assume that 50% will go each way when you don't
know=
 the
> |> |> | impedance of each direction? ?When conducting, or at failure,
the =
MOV has a
> |> |> | very low impedance.
> |> |>
> |> |> There is a distinction between "go each way" and "what comes back"
d=
ue to
> |> |> the impedance. ?It will be about 50% that goes each way _because_
th=
e power
> |> |> itself does not (yet) know the impedance (at a distance), until it
g=
ets
> |> |> there.
> |> |
> |> | Another installment of Phil's Phantasy Physics using transmission
lin=
e
> |> | theory.
> |>
> |> Not understanding it is your loss.
> |
> |
> | I have to agree that this is Phantasy Physics. =A0 =A0We're supposed
to
> | believe that a surge reaching a MOV is going to split 50-50, with half
> | of it going to the MOV path and half moving on down the line,
> | reagrdless of the impedance of the two paths? =A0 =A0That would render
a=
ll
> | surge protection about 50% effective.
>
> You did not read very carefully. =A0The reference to 50-50 split is
about =
the
> contribution of the MOVs themselves. =A0That is an essential
understanding=
 of
> the components so the whole system can be figured out. =A0The impedance
do=
wn
> the paths is another separate component, which also has to be figured in
> when determining the whole picture.
>
> You have confused a component with the entire system. =A0You need to
read =
more
> carefully. =A0Or you need to understand the distinction of individual
comp=
onents
> as they apply to the whole system
>
> The whole wiring system is extrememly complex. =A0It cannot be
understood
> properly without first understanding the components. =A0And that
includes
> understanding that MOVs, when they conduct, do look to the propogating
> energy as two paths to go down, and it will (initially) go both ways in
> about an equal amount.

Maybe you should review what you actually stated in the context of
current surge supression discussion:
"
"The MOVs will act like conductors when they are clamping.  The surge
will
|> |> take both paths ... the path through the MOVs, and the path
going past the
|> |> MOVs.  In general, about 50% will go each way.  That can vary at
higher
|> |> frequencies. "

That sure sounds like 50% of the surge is going through the MOV and
the other 50% is going on past it to the protected equipment.

And that I would have to agree with Bud on, it's phantasy physics,
because if it were true, no type of surge protection would work,
because it would only be 50% effective.



>
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