On Nov 12, 1:28 am, w_tom wrote:
Start with datasheets from MOV manufacturers to understand any surge
protector. Thihs will be long - chock full of tech specs and
concepts.

If the MOV fails catastrophically, then the MOV operates completely
outside "Absolute Maximum Parameters". Its datasheet is quite blunt.
MOVs do not blow like fuses. In fact fuses and MOVs perform two
completely different functions. But those who never learned how plug-
in protectors work will often assume the protector acts like a fuse -
as trader4 has just assumed.

I never claimed that MOV's work like a fuse.



Trader4 implies a protector will disconnect an appliance to stop a
surge.

Never implied that either.



That surge could not be stopped by three miles of sky.

The typical surge arriving at an electronic appliance in your house is
not a direct full lightening strike, so this has zero applicability.

How
does an MOV or fuse then stop or limit it? It only does when one (ie
trader4) has no idea what these components do. As in previous posts,
trader4 will cite no spec numbers, no citations, and cannot even say
how a protector works.

It was clearly explained to you by Bud, but you don't listen, because
you're on some kind of fanatic campaign.



This post will be chock full of engineering
sources, numbers, and quotes because plug-in protectors do not claim
to provide protection AND because one effective 'whole house'
protector with earthing provides massive protection - at tens of times
less money.

How good is protection inside appliances? Trader4 denies this
protection exist, but forgets to provide numbers.

Again, you're making things up. Please show me where I ever said this
doesn't exist. All I said was:

1 - This protection inside the appliance, that you claim is capable of
dealing with surges, is similar to the protection inside a plug-in
surge protector. It has no DIRECT PATH TO EARTH GROUND. Yet you
claim it can defeat surges. So, how is it that this can, but a plug-
in surge protector, operating with the same limitations, cannot?


Industry standards
even in 1970 defined 600 volt transients without damage. Computers
defined in Intel specs must withstand AC electric voltages in the
thousands of volts without damage. If trader4 has learned the
technology, then he knew these well known standards.

I'll compare my engineering and technology qualifications against
you're any day, smart guy.





How many volts much the NIC (network) withstand without damage?
Again, rated for thousands of volts. trader4 calls that minimal
protection? Fine. It is the protection inside electronics that can
be overwhelmed if the surge is not earthed where the surge enters a
building. Internal protection that can be overwhelmed if an adjacent
plug-in protector earths a surge destructively through that
appliance. Protection that means no appliance damaged because surges
are earthed before entering the building. Appliance internal
protection that makes daily (trivial) transients completelyirrelevant.

Again, you're making no sense. Surge components inside the appiance
are peachy keen. But somehow putting similar in a plug-in that also
opperates under the same conditions becomes ineffective and actually
causes destruction? LOL



Trader would have us believe no such protection exists?

Again, you're making things up. Never said any such thing.



Many who
know without first learning the numbers make those claims. Industry
standard for 120 volt computer equipment. It must withstand
transients up to 600 volts without damage. Intel demands even higher
voltages computers. That is the internal protection standard in
electronic appliances. What protects dimmer switches and GFCI from
household generated surges? They all have internal protection.
Protection that may be overwhelmed if the typically destructive surge
is permitted inside the building. One 'whole house' protector properly
earthed means no surge damage.

Bud's citation says protectors work IF there is an earth ground to
divert to. Bud's citations also say a protector too close to
appliances and too far from earth ground may earth a surge .... 8000
volts destructively ... through the adjacent electronics. This is
effective protection? Page 42 Figure 8. Does Trader4 deny that
figure? The adjacent protector earths the surge through TV2 - and
that is effective protection? Either the surge is earthed before
entering the building (effective protection) or the surge is earthed
destructively where? ... 8000 volts through an adjacent TV?


You want to talk about citations? This is like ignoring the 15ft
elephant in the room. The IEEE lightning guide has a whole section
where they talk about plug-in surge protectors. Do they say they
don't work? No. Do they say they cause damage to appliances?
No. Do they say they are a fire hazard? No. They talk about how
they can be used in a home and state:

"The hard-wired protectors will have a higher surge-current rating and
absorb most of the surge, but may not have a low enough limiting
voltage to protect the equipment. Both protectors together work
better than either one alone."

Now, is that clear enough for you? It's exactly what I've been
telling you. It was stated by the 5 authors of the IEEE lightning
guide for homes. You want to attack their credibility or educational
background too?

PS: Don't bother to spew on about the use of the word absorb in the
above statement. Any reasonable person knows they are using that
term loosely and it doesn't mean these degreed EE's think that the MOV
is dissipating the energy instead of shunting it to ground.





If plug-in protectors are so effective as Trader4 says, then where
does the manufacture claim that in numeric specs? Why no listing for
each type of surge AND no protection from that surge? Well, the plug-
in protector may protect from a surge made irrelevant by protection
already inside the appliance. What type of surge does it not protect
from? One that seeks earth ground.

How things are spec'd and whether they don;t work is too different
things.

According to the IEEE, they work.





Every responsible source including IEEE and all of Bud's citations
say that the protector works by earthing. How does the plug-in
protector work without an earth connection? That is the point of
Bud's citations. That is the point of Page 42 Figure 8. No earth
ground connection. So it earths a surge 8000 volts through the TV.

Where does the IEEE make recommendations? Not in pamphlets. IEEE
makes recommendation in standards.


LOL
The reference Bud provided you is straight from the IEEE and targeted
at providing average people with an authoritative source on home
protection. You think it's false, take it up with them.



What does the IEEE Standard 141
(Red Book) say?

In actual practice, lightning protection is achieve by the
process of interception of lightning produced surges,
diverting them to ground, and by altering their
associated wave shapes.

Other IEEE Standards also make similar demands for earthing.
Earthing provides the protection. Even the NIST document (quoted
earlier) says the effective protector works by *diverting* a surge to
earth ground. If a dedicated connection to earth ground does not
exist? Page 42 Figure 8. An 8000 volt surge gets earthed
destructively through the adjacent TV.

As trader4 said, a protector might "limits the differential between
hot-neutral, neutral to ground, hot to ground". Fine. The
typically destructive type of surge is still seeking earth ground.
The protector has distributed (shunted, diverted, connected, clamped)
the surge onto all three wires ... and still seeking earth ground.
Trader4 - stop denying Page 42 Figure 8. The surge is shunted to
other wires. Therefore the surge now has more wires to find earth
ground, 8000 volts destructively, through the adjacent TV.


I should stop denying? LOL. You have the 15ft elephant in the form
of the IEEE document clearly stating how plug-ins do work in direct
contradiction to your rants and I'm the one in denial?



Why do I know this? We have traced surges doing just that. In one
case study, plug-in protectors on some networked computers earthed a
surge into those adjacent computers. The surge passed through network
cards to enter other computers - the path to earth ground. We
literally replaced each damaged IC - traced the path of that surge.
We made network cards and computers functional again because we
learned how surges actually do damage. Protectors did connect the
surge "differential between hot-neutral, neutral to ground, hot to
ground" - as trader4 says. That gave the surge plenty of paths into
the adjacent computers, through the network, and out to earth ground
destructively via another computer. Again, damage occurred because
the protector was too far from earth ground AND too close to
electronics.

Why should I doubt your personal observations? You seemed very
reasonable and balanced. LOL If anyone brought you a TV run over
by a garbage truck, I'm sure after an investigation, you'd say the
damage was caused by a plug-in surge protector.




Only one of us has learned this stuff over many decades by even
designing protectors AND by tracing out resulting failures - or
complete protection. That engineering knowledge is not displayed by
trader4. Trader4 has only posted what retail store salesmen claim.

No, Bud and I posed what the IEEE has to say about it.




I asked how a protector earths a surge without that short connection
to earth. Trader4 said, "Take it up with the IEEE." I did long ago.
And I quoted repeatedly from the IEEE. In every case, effective
protection is defined by earthing as the IEEE says.

But then I went farther - and with numbers. Why does the telco
switching computer connected to overhead wires all over town not
suffer damage? Why does a typical thunderstorm send hundreds of
surges to that switching computer - and no damage? Because every
protector is earthed were wires enter the building AND up to 50 meters
away from electronics. Why do telcos not use plug-in protectors that
trader4 and Bud recommend? They learned 100 years ago what provides
the protection. An earthed protector was even patented in the 1890s.
Earthing. They want protectors that don't create those "scary
pictures".

Then trader4 asks:

So, I can take any size/rating MOV and pass any size current
through it and if it fails, it violates the manufacturer's spec?

Obviously not. But then plug-in protectors often have that problem
- too few MOVs (are so grossly undersized). A surge strikes protector
and computer simultaneously (see how the protector is wired).
Protection inside a computer is so robust that the computer is
unharmed. But the protector inside a power strip is so grossly
undersized as to fail - as trader4 says "blown out". The naive claim
a protector sacrificed itself to save the computer. Reality:
computer saved itself. That same trivial surge destroyed a grossly
undersized protector. This failure promotes sales.


See the part about elephants.




What happens when the same surge is earthed by a properly sized
'whole house' protector? Surge is earthed. Protectors remains
functional. Human never even knows the surge existed. That is
effective protection. But that does not get the naive to promote more
sales of grossly overpriced plug-in protectors - including $150 models
from Monster Cable.

Grossly undersized plug-in protectors sometimes create these scary
pictures:http://www.hanford.gov/rl/?page=556&parent=554
http://www.westwhitelandfire.com/Art...Protectors.pdf
http://www.ddxg.net/old/surge_protectors.htm
http://www.zerosurge.com/HTML/movs.html:
http://tinyurl.com/3x73ol orhttp://www.esdjournal.com/techpapr/Pharr/INVESTIGATING%20SURGE%20SUPP...
http://www3.cw56.com/news/articles/local/BO63312/


I could show you pics where all kinds of appliances and similar
devices in the home caused fires too. That doesn't make them
unsafe. There must be hundreds of millions of surge protectors in
use. Finding a few that malfunctioned is no great revelation.



So who makes 'whole house' protectors? Responsible companies such
as GE, Siemens, Intermatic, Cutler-Hammer, Square D, Leviton, and
others. Notice names missing such as Tripplite, Belkin, APC, and
especially Monster Cable. Let's see. Take a $3 power strip. Apply
some expensive paint. Install some $0.10 protector components. Sell
it for $150. No wonder plug-in protector need people such as Bud to
promote their products. Profits may be at risk. And then those
"scary pictures". Don't put too many MOV inside. That would harm
profits. An undersized (failing) power strip will have the naive
assume, "My protector sacrificed itself to save my computer".

Yes, according to you, we should all rely on the protection inside the
$2000 TV. I suppose no one has ever seen a TV where the internal
protection was blown? LOL. I'd rather see it in a $15 plug-in than
in the $2000 TV. So, would the IEEE, so if you have a problem with
it, take it up with them and get back to us, OK?




Tell us trader4. If the plug-in protector magically protects by
""limits the differential between ...", then were does all that energy
get dissipated? You claim the surge is dissipated by the MOV "between
hot-neutral, neutral to ground," etc. So where does all that energy
get dissipated? Inside a tiny MOV that is doing the limiting? If the
MOV is doing limiting, then the MOV is absorbing all that energy. But
even MOV manufacturers say that is not the purpose of the MOV. Well
...

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