"Clifton T. Sharp Jr." wrote:

w_tom wrote:
Now for your insults - which apparently are due to
insufficient electrical knowledge. [snip]

BTW, MOV degradation is not due to power absorption. It is
due to energy absorption

Wow, a fact! A correct fact! Who told you?

- a major technical difference that
English majors will not understand.

Ah, insults - which apparently are due to insufficient electrical knowledge.

This guy 'w-tom' is a notorious troll on the subject of whole house
surge protectors. He's been doing it for years on other groups. He's
probably a schill for the manufacturers of whole house protectors.


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In article , w_tom
wrote:

A wire also absorbs some power when it shorts a large
current. Does that mean the purpose of a wire is to absorb
electricity? Of course not. MOVs are not installed to absorb
power. But then if one first consults manufacturer
datasheets, then that becomes woefully obvious.

http://www.nteinc.com/Web_pgs/MOV.html
Let's use the 2V130 as example. This device will shunt up to
4500 amps during the standard 8/20 usec surge. A 1000 volt
transient at 4500 amps would be well over 600 joules. But
this device is only rated at 39 joules maximum. How can that
be? Because MOVs, like wire, are not installed to absorb the
energy. They are designed to shunt.

If an MOV was absorbing the transient, then MOV voltage must
increase as more energy is absorbed. That means more voltage
confronts the adjacent appliance. But MOVs don't work that
way. If their purpose was to absorb a transient, then they
must connect in series with the appliance. But MOVs connect
in parallel - a shunt mode device. To be effective as shunt
mode devices (like wire), the MOV must conduct massive
transients and absorb less of that transient. That is what
MOVs do. They shunt. They do not stop, block, absorb, or
filter a transient. They operate like a wire during the
transient. They shunt.

As previously demonstrated from manufacturer datasheets (and
not from wild speculation about what 'joules' measures): If
that MOV in a plug-in protector that can only withstand 3
standard 8/20 microsecond transient, then the larger 'whole
house' protector (that costs about same) will withstand about
300+ such surges. Joules is a measure of MOV life
expectancy. MOVs are not designed to absorb a transient -
which is in direct contradiction to what many web sites,
written by English majors, will claim. The better an MOV,
then the more energy it can shunt - per joule. Read
manufacturer datasheets; not web sites written by English
majors. It is the difference between fact and fiction.

Now for your insults - which apparently are due to
insufficient electrical knowledge. First learn before
insulting others. There is a datasheet. Read it before
posting. Keep it civil - if you can. Posted previously are
accurate electrical engineering facts taken from manufacture
datasheets. Any protector that is damaged by the first surge
is grossly undersized - an ineffective protector usually sold
to those who like to throw money at urban myths.

BTW, MOV degradation is not due to power absorption. It is
due to energy absorption - a major technical difference that
English majors will not understand.

Telamon wrote:
In article , w_tom
wrote:

Any protector that is damaged by the first surge is grossly
undersized. No effective surge protector can be damaged. They
are not sacrificial devices as urban myth purveyors will claim.

The characteristics of MOV's are well known. Every time a MOV turns
on due to the device threshold being exceeded they degrade based
on how much power is absorbed.

If you are whom I think you are the facts won't bother you one bit
and further nonsense posts can be expected.

The notorious Tom troll.

Explaine the meaning of the chart "Peak current per pulse versus pulse
duration" at the top of this page.

http://www.worldproducts.com/MOVPeakPulse.htm

I see you are still up to par with your long winded nonsense and you
still have not learned to post to Usenet properly either.

Up next... a kill file update.

--
Telamon
Ventura, California

HFguy wrote:

This guy 'w-tom' is a notorious troll on the subject of whole house
surge protectors. He's been doing it for years on other groups. He's
probably a schill for the manufacturers of whole house protectors.

I put in one of those units last week. The instructions on the back of
the package say to connect the two leads of the device to the two power
lines where they enter the house OR inside of the meter base on two of
the lugs. (Highly illegal and unsafe, too).

Pure stupidity on the part of the manufacturer. This is a major law suit
waiting to happen. I don't know how it got past the 'certification' types.

I wound up wiring the thing into it's own two pole 15A. breaker via a
half inch knockout on the side of the panel. It's the ONLY way to do it
right.


mike

--
__ __ __ __ __ __ __ __
/ /\ / /\ / /\ / /\ / /\ / /\ / /\ / /
/ /\ \/ /\ \/ /\ \/ /
/_/ \/_/ \/_/ \/_/ \/_/ \/_/ \/_/ \/_/

..let the cat out to reply..

Name of manufacturer and model number? Where were the
important leads to earth ground. It only had two leads?

Rather surprised so little knowledge here about how
effective protection has long been installed. After all,
earliest research was on amateur radio equipment. Much of
what we know about protection today - why 'whole house'
protectors are so effective - was proven by early 1900s radio
amateurs. In the radio industry, properly earthed surge
protector are so well appreciated that these industry
benchmark application notes are considered legendary. Do they
discuss their product line? Of course not. They discuss the
most important feature in any surge protection system -
earthing:
http://www.polyphaser.com/ppc_pen_home.asp

A surge protector being only as effective as its earth
ground.

m II wrote:
I put in one of those units last week. The instructions on the back
of the package say to connect the two leads of the device to the
two power lines where they enter the house OR inside of the meter
base on two of the lugs. (Highly illegal and unsafe, too).

Pure stupidity on the part of the manufacturer. This is a major
law suit waiting to happen. I don't know how it got past the
'certification' types.

I wound up wiring the thing into it's own two pole 15A. breaker via
a half inch knockout on the side of the panel. It's the ONLY way to
do it right.

In article
,
Telamon wrote:

snip

Telamon wrote:
In article , w_tom
wrote:

Any protector that is damaged by the first surge is grossly
undersized. No effective surge protector can be damaged. They
are not sacrificial devices as urban myth purveyors will claim.

The characteristics of MOV's are well known. Every time a MOV turns
on due to the device threshold being exceeded they degrade based
on how much power is absorbed.

If you are whom I think you are the facts won't bother you one bit
and further nonsense posts can be expected.

The notorious Tom troll.

Explaine the meaning of the chart "Peak current per pulse versus pulse
duration" at the top of this page.

http://www.worldproducts.com/MOVPeakPulse.htm

I see you are still up to par with your long winded nonsense and you
still have not learned to post to Usenet properly either.

Up next... a kill file update.

Answering my own post because Tom can't.

I figured you could not answer a simple question.

--
Telamon
Ventura, California

Posted by worldproducts.com is a chart demonstrating MOV
life expectancy for various pulse widths and peak current - as
was described in the previous post. Chart simply demonstrates
how an MOV degrades; not self destructs. As stated earlier,
an MOV self destructs when operating well outside the ratings
of that chart - when grossly undersized - insufficient joules
to provide effective protection.

Any MOV that 'sacrifices itself' does not even appear on
the chart and does not provide effective protection. Any MOV
that 'sacrifices itself' was grossly undersized - ineffective
protection.

Telamon wrote:
Explaine the meaning of the chart "Peak current per pulse versus pulse
duration" at the top of this page.

http://www.worldproducts.com/MOVPeakPulse.htm

I see you are still up to par with your long winded nonsense and you
still have not learned to post to Usenet properly either.

Up next... a kill file update.

Over the years I have replaced dozens of MOVs in my
numerous high-end surge-limiting power strips rather than
shell out another couple hundred dollars for new strips
after major power company events. I get on average a year's
life out of the strips before another power company event
comes along.
The cause of some of these events is known. Another
power company had three-phase lines going over the
street-side power lines. Under certain wind conditions they
would make contact. I observed a large, long 1/2 second
over-voltage event that blew out the breaker panel
suppressor and at least one MOV in each power strip with a
bang and smoke.
Other times lightning would induce the event. I
theorize that a flashover resulted in a nearby power company
voltage regulator's (a big variac) storage of a large amount
of energy due to large following currents. Somehow this
energy then dumps onto the street-side lines, causing
another failure of the surge protectors. The power company
regulator also failed to 8% high and this may have
contributed to the problem.
But the AC system and major household appliances were
not damaged. This indicates that while there was a serious
over-voltage, it was not enough to pierce the insulation on
motor windings and an unprotected wall wart.
Anyway, I bought a few dozen replacement MOVs and 3 or 5
amp pigtail fuses for repairs. Usually just one MOV and
fuse fail per strip. The strip can be recovered with
sufficient skill.
Good surge protector strips have inductors in them to
block the high frequency components of the surge.
Otherwise, plugged-in power transformers without effective
shielding between the primary and secondary (typical) can
pass along these potentially large high-frequency components
to the following circuitry.
In my case, 130V MOVs for the 125VAC service would blow
out at the next event. So I upped the replacements to 150V
with some hope that it will make a difference.
The replacement fuses are standard AGC 250V sized at 3
or 5 Amp. They really take a beating when one of these
events comes along. The inside surface of the glass fuse
body has lots of metal globules embedded in the glass.
Professional lightning protection systems use a
multi-layered approach. It used to be that Polyphaser Corp
sold a book called "The 'Grounds' for Lightning and EMP
Protection" that described this in usable engineering terms.
Now they don't offer it on the website as far as I can tell.
Just salesman's faqs.

Henry










As a result of recent events, I have two surge protectors that no longer
function without putting out loud noises on HF. I found that the $5
surge protector that my Yaesu was plugged in to was making a loud
whistling noise which was covered up by the louder warbling noise being
made by the Belkin I had my computer plugged into. So I decided to break
them open to see what was inside. The easiest was Old El Cheapo, held
together with screws. Inside was a length of wire, a switch and ONE disc
capacitor wired into six plugs. IMO that's little better than a plain
old power strip. The Belkin had no screws, so it took a little longer to
crack. The results: a switch, two LEDs ("protected" and "grounded"), an
inductor coil, a couple resistors and transistors, and about 9 or 10
disc capacitors in series. In October 2002 the Belkin cost me $40. I'm
hard pressed to say that it was money well spent, if all that's in there
are some capacitors and resistors. Question: are surge protectors worth
it if all they are is just a bunch of capacitors? I know that my $40
surge protector apparently rolled over and died when hit with a real
surge.



Email address: "see_signature" - "a0015717"
Newsgroup replies may serve better the public interest.

In article ,
"Clifton T. Sharp Jr." wrote:

w_tom wrote:
Any MOV that 'sacrifices itself' does not even appear on
the chart and does not provide effective protection. Any MOV
that 'sacrifices itself' was grossly undersized - ineffective
protection.

You can't produce a protection device that will not sacrifice itself
given a direct lightning strike, not even a 10" diameter solid steel
rod.

Your constant repetition of this silliness does not make it true.

w_tom is a complete idiot. The sooner you kill file him the sooner he
will leave the group and go bother someone else.

--
Telamon
Ventura, California

Clifton's posts without technical details. Common among
naysayers, who know but cannot even be bothered to learn the
numbers, is this classic example of technical naivety:
You can't produce a protection device that will not sacrifice
itself given a direct lightning strike, not even a 10"
diameter solid steel rod.

Yes, Clifton would have us believe that lightning could
vaporize a 10" diameter steel rod. He did not even post how
many amps must be in a lightning strike to vaporize that 10
inch diameter steel rod!

Instead we learn from industry professionals:
http://www.harvardrepeater.org/news/lightning.html
Well I assert, from personal and broadcast experience spanning 30
years, that you can design a system that will handle *direct
lightning strikes* on a routine basis. It takes some planning
and careful layout, but it's not hard, nor is it overly
expensive. At WXIA-TV, my other job, we take direct lightning
strikes nearly every time there's a thunderstorm. Our downtime
from such strikes is almost non-existant. The last time we went
down from a strike, it was due to a strike on the power
company's lines knocking *them* out, ...
Since my disasterous strike, I've been campaigning vigorously
to educate amateurs that you *can* avoid damage from direct
strikes. The belief that there's no protection from direct
strike damage is *myth*. ...
The keys to effective lightning protection are surprisingly
simple, and surprisingly less than obvious. Of course you
*must* have a single point ground system that eliminates all
ground loops. And you must present a low *impedance* path for
the energy to go. That's most generally a low *inductance*
path rather than just a low ohm DC path.

Only the naive would believe one needs $thousands to install
an earthing system. And yet that is what Clifton would have
us believe.

If a surge protector fails, then it was clearly undersized
for the task. Surge protectors should be so effective that
one never knows it did its job - in direct contradiction to
what Clifton posts. The most critical component in surge
protection is earthing. Direct lightning strike without
damage is routine. Clifton would even deny this. A surge
protector is only as effective as its earth ground. No earth
ground means no effective surge protection. Clifton has some
wild idea that sacrificial MOVs will provide the protection -
which is why he insults rather than post a single technical
number. Instead Clifton would have us believe that lightning
would vaporize a 10 inch diameter steel rod - without even a
single numerical fact.

"Clifton T. Sharp Jr." wrote:
...
w_tom wrote:
In the radio industry, properly earthed surge
protector are so well appreciated that these industry
benchmark application notes are considered legendary.

The radio industry can afford hundred-thousand-dollar Ufer grounds
and ten-thousand-dollar lightning shunts. And radio stations STILL
go down in storms from lightning strikes.

Do they discuss their product line? Of course not. They discuss
the most important feature in any surge protection system -
earthing:
http://www.polyphaser.com/ppc_pen_home.asp

A surge protector being only as effective as its earth
ground.

The radio industry can afford hundred-thousand-dollar Ufer grounds and
ten-thousand-dollar lightning shunts. And radio stations STILL go down
in storms from lightning strikes.

w_tom wrote:

Only the naive would believe one needs $thousands to install
an earthing system. And yet that is what Clifton would have
us believe.

If a surge protector fails, then it was clearly undersized
for the task. Surge protectors should be so effective that
one never knows it did its job - in direct contradiction to
what Clifton posts. The most critical component in surge
protection is earthing. Direct lightning strike without
damage is routine. Clifton would even deny this. A surge
protector is only as effective as its earth ground. No earth
ground means no effective surge protection. Clifton has some
wild idea that sacrificial MOVs will provide the protection -
which is why he insults rather than post a single technical
number. Instead Clifton would have us believe that lightning
would vaporize a 10 inch diameter steel rod - without even a
single numerical fact.

Hey w-tom,

Why are you obsessed with posting countless diatribes on the subject of
surge protectors on dozens of newsgroups? Are you a shill for the whole
house surge protector industry?


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