Re: Surge / Ground / Lightning

trader4@[EMAIL PROTECTED]
 wrote:
> On May 5, 2:20 pm, 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-nos...@[EMAIL PROTECTED]
 wrote:
>> |>
>> |> |> In alt.engineering.electrical Leonard Caillouet
<nos...@[EMAIL PROTECTED]
> wrote:|> | <phil-news-nos...@[EMAIL PROTECTED]
> wrote in message
>> |>
>> |> |> |news:fvjhvk016vr@[EMAIL PROTECTED]
>> |> |> |> In alt.tv.tech.hdtv Franc Zabkar <fzab...@[EMAIL PROTECTED]
>
wrote:
>> |> |> |
>> |> |> |>
>> |> |> |> 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.
>> |> |> |
>> |> |> | 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" due to
>> |> |> the impedance. ?It will be about 50% that goes each way _because_
the power
>> |> |> itself does not (yet) know the impedance (at a distance), until
it gets
>> |> |> there.
>> |> |
>> |> | Another installment of Phil's Phantasy Physics using transmission
line
>> |> | theory.
>> |>
>> |> Not understanding it is your loss.
>> |
>> |
>> | I have to agree that this is Phantasy Physics.    We'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?    That would render
all
>> | surge protection about 50% effective.
>>
>> You did not read very carefully.  The reference to 50-50 split is about
the
>> contribution of the MOVs themselves.  That is an essential
understanding of
>> the components so the whole system can be figured out.  The impedance
down
>> 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.  You need to read
more
>> carefully.  Or you need to understand the distinction of individual
components
>> as they apply to the whole system
>>
>> The whole wiring system is extrememly complex.  It cannot be understood
>> properly without first understanding the components.  And 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.

He is using transmission line effects which Martzloff investigated and 
said do not come into play unless the circuit is 200m long. Phil claims 
high frequencies.

Still missing - a source that sup****ts nanosecond risetimes and 100MHz 
spectrum.

-- 
bud--