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In alt.engineering.electrical wrote:
| On May 5, 1:44?am, wrote:
| In alt.tv.tech.hdtv bud-- wrote:| wrote:
|
| | In alt.engineering.electrical Leonard Caillouet wrote:| | wrote in message
|
| | ...
| | | In alt.tv.tech.hdtv Franc Zabkar 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.

--
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| Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |