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Bud--

wrote:
In alt.tv.tech.hdtv bud-- wrote:
| wrote:
| In alt.tv.tech.hdtv bud-- wrote:

| | You suggest experts in the field "missed a lot of reality" and "flubbed
| | the experiment".
|
| I propose that as one explanation as to why these guides come up short on
| the explanations.
|
| Translation - they don't say what you believe. They "missed a lot of
| reality" was in response to one of your beliefs that is not found in any
| of the rather extensive reading I have done. And another of your beliefs
| for which you have no supporting cite.

You are likely to never see any citation that attests to what I believe.

Because some of what you believe has nothing to do with the real world.

| And you are again discounting a guide written by experts, peer reviewed
| by experts, published by the IEEE, and aimed at technical people. You
| apparently think electrical engineers are idiots. Where you disagree
| with the guide you have not cited a source that supports your belief.

I've _met_ electrical engineers that are idiots. I've met people in a
lot of other fields that are idiots.

I don't know if the authors of what you have read are idiots. Maybe they
are just not writing as broadly as you think they are.

Of course they are idiots. They are all members of the IEEE. Only idiots
can join. And only the biggest idiots can write publications for the IEEE.

Martzloff is not only an IEEE idiot. He worked for the NIST - another
well known lair of idiots.

Thank goodness you aren’t a member.

| For example, consider the high frequency issue. High frequency energy is
| less common than low frequency energy. Partly this is because the chance
| of a closer lightning strike is less than a more distant one. A strike
| within 100 meters is only 1/8 as like as a strike outside of 100 meters
| but within 300 meters. Some people then feel that they can dismiss high
| frequency energy issues entirely.
|
| Francois Martzloff was the surge guru at the NIST and has many published
| papers on surges and suppression. In one of them he wrote:
| "From this first test, we can draw the conclusion (predictable, but too
| often not recognized in qualitative discussions of reflections in wiring
| systems) that it is not appropriate to apply classical transmission line
| concepts to wiring systems if the front of the wave is not shorter than
| the travel time of the impulse. For a 1.2/50 us impulse, this means that
| the line must be at least 200 m long before one can think in terms of
| classical transmission line behavior."
| Residential branch circuits aren't 200m.
|
| Your response: "Then he flubbed the experiment." In another case you
| have said Martzloff had a hidden agenda.

I addressed this one elsewhere. You seem to have misunderstood him.
He did not say that wiring systems do not exhibit transmission line
characteristics.

If you had actually read the quote:
"*it is not appropriate to apply classical transmission line concepts to
wiring systems*"
and "*this means that the line must be at least 200 m long before one
can think in terms of classical transmission line behavior*."

Repeating: "Residential branch circuits aren't 200m."

Rather, he points out that one does not need to look
at the transmission line characteristics in certain cases.

Like branch circuits under 200 meters long.

| You claim lightning induced surges have rise times about a thousand
| times faster than accepted IEEE standards - which are experimentally
| derived.

So you are narrowing this statement to only induced surges?

I intended "induced" meaning produced by including the most damaging -
strikes to utility lines.

I didn't see where you quoted anything by IEEE or its experts that specify
actual rise times of any kind of surge, induced or otherwise.

From the Martzloff quote you didn't read:
"For a 1.2/50 us impulse". That is 1.2 microseconds rise time.

From w_'s favorite engineer source "an 8 microsecond rise time".

Don’t you read anything?

The numbers come from an IEEE standard - accepted by everyone but you.

| One of w_'s favorite professional engineer sources says an 8 microsecond
| rise time for a lightning induced surge is a "representative pulse",
| with most of the spectrum under 100kHz. You don?t get transmission line
| effects at 100kHz.

I agree that you don't get transmission line effects under 100 kHz for 200m
wires ... of any significance to worry about for surge matters.

OTOH, you have not shown how even if an 8 microsecond rise time is significant
as a representative case, that it can't get shorter than that in severe cases.
or even a higher rise voltage (which hasn't even been specified at all here).

I provided 2 direct sources. They follow IEEE standards for rise time.

Still never seen - a cite that supports your opinion.
It is Phil’s phantasy physics.

--
bud--