MOVs and surge suppressors

100 joules is a small protector. But small protector is standard in
so many plug-in UPSes that claim to have protection. It contains near
zero joules. Near zero joules is just enought to claim it does surge
protection. How many notices the near zero joules in so many UPSes
recommended for surge protection? Myths such as this also promote
ineffective plug-in protectors. Bud's job is to keep you confused so
that you don't learn why his protects with their massive profit
margins are so ineffective.

More of Bud's intentional lies. For example, irrelevant is what
happens to surge on neutral wire. The same surge on black wire is
still seeking earth ground. Make no different whether that surge is
on any other wire. That surge is still on black wire and still
seeking earth ground inside a building. Bud knew that. He spins a
lie hoping you had no idea what transverse mode means and only become
confused. He intentionally lies knowing that confusion causes the
reader to ignore technical reality and to only believe popular urban
myths.

Since Bud is promoting for plug-in protector manufacturers, since
those protector claim no protection from the destructive type of
surge, AND since those protectors have no earthing wire, then Bud
must spin myths and intentionally lie to confuse the importance of
earthing. If you forget that earthing provides the protection, then
you will spend tens (maybe 100) times more money per protected
appliance for his ineffective products.

If earthing was not critical; if earthing did not provide protection
- then why do all facilities that cannot suffer surge damage center
their protection system around the most critical component of that
protection 'system'? Single point earth ground. Why do they not
waste money on plug-in protectors that are grossly overpriced and
typically undersized? Bud will say anything to pervert this reality:
protection is earth ground. The protector is only as effective as its
earth ground.

Why did the adjacent TV on Page 42 Figure 8 get damaged by a surge
seeking earth ground? According to Bud, surge was not seeking earth
ground because the neutral wire was earthed. Even with an earthed
neutral wire, that surge was permitted inside the building,
distributed to other wires, and therefore found earth ground
destructively via an adjacent TV. Why did the surge seek earth ground
when Bud says it is transverse mode - does not seek earth ground? Who
do we believe? Bud or his citation - Page 42 Figure 8. Since the
surge was not earthed before entering a building.... well Bud claims
everything needs a plug-in protector - meaning $2000 or $4000 of these
ineffective protectors. Massive profits on protectors that don't even
claim to protect from a surge that causes TV damage on Page 42 Figure
8. But that protector is so profitable.

Page 42 Figure 8 - a surge that Bud claims is transverse mode
because neutral wire is earthed, instead, found earth ground
destructive via an adjacent TV. Surge energy must be dissipated
somewhere AND must find a path to earth ground. On Page 42 Figure 8
of Bud's own citation: 8000 volts destructively through the TV.

Bud repeatedly cites Martzloff - but only the parts that promote his
half truths. Meanwhile even Martzloff says plug-in (point of use)
protectors may create appliance damage. A point so important in
Martzloff's 1996 IEEE paper that the point is conclusion number one:
Conclusion:
1) Quantitative measurements in the Upside-Down house clearly
show objectionable difference in reference voltages. These occur
even when or perhaps because, surge protective devices are
present at the point of connection of appliances.
What are the destructive surges that Martzloff studies? Its not
transverse mode. They are made irrelevant by protection inside
appliances. Destructive surges seek earth ground. Ground the
typically destructive surge either without damage via a 'whole house'
protector or direct earth ground connection, OR with damage
destructively via household appliances. But again, what does
Martzloff discuss, what is demonstrated on Page 42 Figure 8, and what
does Bud avoid discussing? Protection is defined by earthing because
destructive surges seek earth ground.

Bud even lies about what his own citations say. Both say how a
protector might work AND how protectors can even create appliance
damage if the surge is not earthed. Even his own citation says the
protector should really be called a diverter because the effective
protector diverts surges to earth. Did Bud forget to mention that
part again? Yes. His intent is to create confusion - to protect
sales of those grossly overpriced and ineffective plug-in protectors
that high reliability facilities don't even waste money on.

On Sep 4, 10:56 am, bud-- <remove.BudN...@isp.com> wrote:
w_ has said elsewhere that MOVs do not dissipate much of the energy of a
surge.

100J would be very small for a plug-in suppressor. Very high ratings are
readily available.

The current (and energy dissipation) at a plug-in suppressor is limited
by the impedance of the branch circuit wiring to a surge.

If a surge comes in on power lines, with no service panel suppressor,
there will be arc-over at panels and receptacles at about 6000V.
Arc-over at the service panel dissipates most of a really large surge.
(But service panel suppressors are a good idea.)

In the US, any surge entering on the service neutral is directly earthed
by the neutral-ground bond. Beyond the service, all surges will be
transverse mode.
...

The lie repeated. The plug-in suppressor protected the TV connected to
it. It lowered the surge voltage at the 2nd TV. The point for the IEEE
and anyone who can think is "to protect TV2, a second multiport
protector located at TV2 is required." The cause of problems is a
'ground' wire from the cable entry to the power service that is too
long, which is the case in many houses. The guide says when that happens
"the only effective way of protecting the equipment is to use a
multiport protector."

A power service suppressor would provide *no* protection to either TV.
...

Take a service panel suppressor in a system with a single ground rod.
With a modest 1000A surge current to earth and a very good 10 ohms
resistance to earth there will be 10,000V from the system ground to
'absolute' earth. As a rule of thumb, 70% of the voltage drop from a
ground rod is in the first 3 feet from the rod. The voltage from system
ground to earth beyond 3 feet from the rod will be 7,000V or more. That
is most of the house in contact with the earth.
...
 
w_tom wrote:

More of Bud's intentional lies. For example, irrelevant is what
happens to surge on neutral wire.
And the lie was what???

w_ asked where the surge went. I explained that any of the surge that
enters on the neutral is directly earthed by the neutral-ground-earth
bond. w_ apparently doesn’t want an explanation of where the surge goes.

The same surge on black wire is
still seeking earth ground. Make no different whether that surge is
on any other wire. That surge is still on black wire and still
seeking earth ground inside a building. Bud knew that.
I said that for the surge on the hot wires there is arc-over at the
service panel at about 6000V that dumps most of the surge to earth. w_
has a disability where he can’t understand anything that does not
conform to his quack views.


He intentionally lies knowing that confusion causes the
reader to ignore technical reality and to only believe popular urban
myths.
And the lie was what???

I posted links to reputable sources on plug-in suppressors which I
recommend you read.
w_ only has his own bizarre ideas.

Since Bud is promoting for plug-in protector manufacturers
To quote w_ "It is an old political trick. When facts cannot be
challenged technically, then attack the messenger." My only association
with surge protectors is I have some.

With no technical arguments, w_ has to discredit those that oppose him.

since those protectors have no earthing wire, then Bud
must spin myths and intentionally lie to confuse the importance of
earthing.
And the lie was what???

Because it does not conform to his quack views, w_ cannot understand
when the IEEE guide explains plug-in suppressors work primarily by
clamping the voltage on all wires (power and signal) to the common
ground at the suppressor. And that earthing occurs elsewhere.


The protector is only as effective as its
earth ground.
The required statement of religious belief in earthing.

Why did the adjacent TV on Page 42 Figure 8 get damaged by a surge
seeking earth ground? According to Bud, surge was not seeking earth
ground because the neutral wire was earthed.
Poor w_ has lost the ability to think. Earthing the neutral is not
terribly relevant to the IEEE illustration. The illustration, for the
IEEE and anyone who can think, is that "to protect TV2, a second
multiport protector located at TV2 is required."

The guide says that with the problem shown in the illustration, a
‘ground’ wire from a cable entry block that is too long, "the only
effective way of protecting the equipment is to use a multiport
protector." Long ground/bond wires are a problem in many homes.

And w_ has still not explained how a service panel suppressor would
protect either TV in the illustration. Perhaps that is because a
service panel suppressor would provide no protection.


Bud repeatedly cites Martzloff - but only the parts that promote his
half truths. Meanwhile even Martzloff says plug-in (point of use)
protectors may create appliance damage. A point so important in
Martzloff's 1996 IEEE paper that the point is conclusion number one:
I don’t repeatedly cite Martzloff.

w_ quotes only what he thinks promotes his half truths. w_ forgets to
mention that Martzloff said in the same 1994 (not 1996) document:
"Mitigation of the threat can take many forms. One solution. illustrated
in this paper, is the insertion of a properly designed surge reference
equalizer [multiport plug-in surge suppressor]."

In 2001 Martzloff wrote the NIST guide which says plug-in suppressors work.

Because plug-in suppressors violate w_'s religious belief in earthing
he has to twist what Martzloff says about them.


What are the destructive surges that Martzloff studies? Its not
transverse mode. They are made irrelevant by protection inside
appliances.
w_ has not explained how a common mode surge gets past the
neutral/ground/earth bond at US service panels.


Everyone is in favor of earthing. The only question is whether plug-in
suppressors work.
Martzloff and the IEEE and NIST guides say plug in suppressors are
effective.

Still no link from another lunatic that says plug-in suppressors are NOT
effective. All you get is w_’s quack views based on his religious beliefs.


As always no answers to simple questions:
- Why do the only 2 examples of protection in the IEEE guide use plug-in
suppressors?
- Why does the NIST guide says plug-in suppressors are "the easiest
solution"?
- How would a service panel suppressor provide any protection in the
IEEE example, pdf page 42?
- Why does the IEEE Emerald book include plug-in suppressors as an
effective surge protection device.
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed surge reference equalizer
[multiport plug-in surge suppressor]."
Why no answers w_?


Bizarre claim - plug-in surge suppressors don't work
Never any sources that say plug-in suppressors are NOT effective.
Twists opposing sources to say the opposite of what they really say.
Invents opinions and attributes them to others.
Attempts to discredit opponents.
w_ is a prevaricator and a purveyor of junk science.

--
bud--
 
On Sun, 02 Sep 2007 17:02:22 -0700, w_tom <w_tom1@usa.net> wrote:

A surge has energy. If voltage is limited, then where is
the energy dissipated?
True. The energy has to go elseware.
 
Ken wrote:
On Sun, 02 Sep 2007 17:02:22 -0700, w_tom <w_tom1@usa.net> wrote:


A surge has energy. If voltage is limited, then where is
the energy dissipated?


True. The energy has to go elseware.
The simple fact is that electrical energy gets
converted to heat energy whenever there is current
through resistance in the path 6the current takes,
in accordance with P = I^2R.

The energy in the case of a point of use protector
is what comes out of the panel and travels through the
specific branch circuit wiring to the MOV, *not* the
entire energy in the source outside of the house
(presumably lightning), or even the entire energy
that gets through the panel and splits among all
the branch crcuits.

What the point of use protector is clamping is the
let through voltage on the specific circuit, and the
MOV doesn't "see" all of it while it is clamping - some
is dropped in the wiring.

The energy is dissipated in the path from the panel to
the MOV protector, the MOV itself, and the path from the
MOV back to the panel. Electrical energy is converted
to heat, in accordance with ohm's law:

-- I-->
| |----PathR(t)----+
S |P | |
U--|A | MOVr
R--|N | |
G |E | |
E |L |----PathR(b)----+
| |
--

The energy will go to three places and be
converted to heat in each place:

Some energy will be converted to heat in the
top path as follows: I^2 * PathR(t) In conjunction
with the energy going to heat, there will be a
voltage drop in the path of V = I * PathR(t)

Some will be converted to heat in the MOV
as follows: I^2 * MOVr In conjunction with the energy
going to heat, there will be a voltage drop in the
MOV of V = I * MOVr

Some will be converted to heat in the
bottom path as follows: I^2 * PathR(b)
In conjunction with the energy going to heat, there
will be a voltage drop in the path of V = I * PathR(b)

The voltage across the MOV will be clamped by the
MOV to some value much lower than the let through
voltage, until the MOV dies or the let through
voltage drops below the level that keeps the MOV
in the low resistance state. 340 volts is a typical
clamping voltage spec.

Ed
 
On Sep 7, 5:33 am, Ken <_ken...@telia.com> wrote:
On Sun, 02 Sep 2007 17:02:22 -0700, w_tom <w_t...@usa.net> wrote:
A surge has energy. If voltage is limited, then where is
the energy dissipated?

True. The energy has to go elseware.
Some are claiming an MOV protector without earth ground is
sufficient protection. Somehow all that surge energy will be absorbed
by wires. And that current will stop seeking what it wants to connect
to - earth ground. Effective protectors are sold on science. The
energy is diverted to earth 1) so that the electrical path is via
things not damaged, and 2) so that the energy is absorbed in earth.
Wires and the MOV do not absorb all that energy as ehsjr claims.

In effective protection, little energy is absorbed by wires and
MOV. Massive energy is absorbed in earth. Only with proper earthing
is a little protector is so massively effective. That energy has to
go elsewhere. Those promoting protectors without earthing simply
pretend that energy it trivial or does not exist.

A protector is only as effective as its earth ground. Earth is
where surge energy must be absorbed - not inside an MOV protector as
ehsjr so often claims.
 
w_tom wrote:
On Sep 7, 5:33 am, Ken <_ken...@telia.com> wrote:
On Sun, 02 Sep 2007 17:02:22 -0700, w_tom <w_t...@usa.net> wrote:
A surge has energy. If voltage is limited, then where is
the energy dissipated?
True. The energy has to go elseware.
I gave a short answer where the energy goes in my post dated 9-4.

Some are claiming an MOV protector without earth ground is
sufficient protection.
Among those that claim a plug-in suppressor is effective are the IEEE
and NIST .

Somehow all that surge energy will be absorbed
by wires. And that current will stop seeking what it wants to connect
to - earth ground.
The IEEE guide explains that earthing does not occur primarily through a
plug-in suppressor. The IEEE guide explains earthing occurs elsewhere in
the circuit.


Wires and the MOV do not absorb all that energy as ehsjr claims.
Complete mischaracterization of what Ed said in his last post.


Those promoting protectors without earthing simply
pretend that energy it trivial or does not exist.
Those who say plug-in suppressors are effective include the IEEE and
NIST. But poor w__ can’t figure out how they work because thry biolate
his religious belief in earthing.

A protector is only as effective as its earth ground.
The required statement of religious belief in earthing.
Everyone is in favor of earthing. The only question is whether plug-in
suppressors work.

Both the IEEE and NIST guides say plug in suppressors are effective.
Read the sources.

w_ has still never found another lunatic that says plug-in suppressors
are NOT effective.

And w_ has still not answered simple questions:
- Why do the only 2 examples of protection in the IEEE guide use plug-in
suppressors?
- Why does the NIST guide says plug-in suppressors are "the easiest
solution"?
- How would a service panel suppressor provide any protection in the
IEEE example, pdf page 42?
- Why does the IEEE Emerald book include plug-in suppressors as an
effective surge protection device.
- Why did Martzloff sayin his paper "One solution. illustrated in this
paper, is the insertion of a properly designed surge reference equalizer
[multiport plug-in surge suppressor]."


Bizarre claim - plug-in surge suppressors don't work
Never any sources that say plug-in suppressors are NOT effective.
Twists opposing sources to say the opposite of what they really say.
Invents opinions and attributes them to others - like Ed.
Attempts to discredit opponents.
w_ is a prevaricator and a purveyor of junk science.

--
bud--
 
On Tue, 11 Sep 2007 09:33:16 -0500, bud-- <remove.BudNews@isp.com>
wrote:

Both the IEEE and NIST guides say plug in suppressors are effective.
Yes, but only if they are connected in the right way.
They have to route the energy to ground.
 
Ken wrote:
On Tue, 11 Sep 2007 09:33:16 -0500, bud-- <remove.BudNews@isp.com
wrote:

Both the IEEE and NIST guides say plug in suppressors are effective.


Yes, but only if they are connected in the right way.
They have to route the energy to ground.

Have you read the illustration in the IEEE guide starting pdf page 40.
The illustration has a surge coming in on a CATV cable. The 'ground'
wire connecting the CATV entry block to the power service ground is 30
feet - far too long (not a "single point ground"). As a consequence, the
CATV wiring is at 10,000V with respect to the power wiring.

The illustration shows that protection is provided by connecting the
cable wire sheath (ground) the power ground wire at a plug–in suppressor
and clamping the voltage on all the wires to the common ground at the
suppressor. The voltages on the wires going to the TV are safe for the TV.

The illustration explains that the “vast majority” of the earthing of
the surge occurs through the 'ground' wire from the CATV entry block to
the power service, as the NEC intended. Not much of the surge is earthed
through the plug-in suppressor. But the suppressor protects the TV
connected to it.

(In this case, a electric service panel surge protector will not help.
The guide says in this case "the only effective way of protecting the
equipment is to use a multiport protector".)

-----------------
If a surge enters through the power service without a service panel
suppressor, the surge energy entering on the neutral is earthed directly
by the neutral-‘ground’ bond required in US service panels. For a large
surge, the surge energy entering on the hot wires will cause arc-over
from hot to ‘ground’ at the service panel (and receptacles) at about
6000V. Arc–over will dump most of the remaining surge energy to the
earth and limits the voltage to something under 6000V. A service panel
surge suppressor would be preferable. (In any case, a large surge
current to earth will raise the voltage of the system ‘ground’ above
‘absolute ground’ by thousands of volts).

A plug--in suppressor in this case will still work by clamping the
voltage on all wires to the common ground at the suppressor. Because the
impedance of the branch circuit wires is high, not much of the surge
energy left after arc-over will reach the plug-in suppressor (unless
the branch circuit wiring to the panel is very short). Because a surge
is a very fast event the inductance of the wire is much more important
than the resistance.

-------------------
Plug-in suppressors do *not* work primarily by earthing a surge.
Earthing occurs elsewhere.


--
bud--
 
John Doe wrote:

w_tom <w_tom1@usa.net> wrote:

Where is energy absorbed after being *shunted* by an MOV?

It's not shunted by the MOV, it's absorbed elsewhere.

It's been explained to w_tom a dozen times. The function is simple
enough for anyone with a basic understanding of electricity (like me).

The Metal Oxide Varistor (MOV) clamps the terminals of the circuit so
that they are the same voltage. When two points are at the same
voltage, there is no current flow and nothing gets destroyed, no
matter what the voltage. All that's left is for the surge to subside.
The MOV does not clamp to 0 volts. Perhaps you should review some MOV specs.

Here are some.
http://www.nteinc.com/Web_pgs/MOV.html

Note the column called Maximum Clamping Voltage. How does this fit with
your "clamps the terminals of the circuit so that they are the same
voltage" statement?

Also note the Continuous voltage columns. At or below these voltages the MOV
also does basically nothing.

When there are zero volts across the MOV it does nothing.

And, what do you think the transient energy column means?

When clamping the voltage in a circuit to some value, how much energy is
going into the MOV?
 
w_tom wrote:

On Aug 30, 11:02 am, bud-- <remove.BudN...@isp.com> wrote:
...
Francois Martzloff, who was the NIST guru on surges and author of the
NIST guide, has written "the impedance of the grounding system to `true
earth' is far less important than the integrity of the bonding of the
various parts of the grounding system." That is, a 'single point ground'
with short interconnect wires.
...

Bud routinely misrepresents facts by selective posting. Even
Martzloff said what Bud fears you might learn. A point so important
that Martzloff makes this the very first point in his 1996 IEEE paper:
Conclusion:
1) Quantitative measurements in the Upside-Down house clearly
show objectionable difference in reference voltages. These occur
even when or perhaps because, surge protective devices are
present at the point of connection of appliances.

Point or use (plug-in) protectors can even contribute to damage of
adjacent appliances. But then that reality was demonstrated here.
Where does surge energy get dissipated when a point of use (plug-in)
protector has no earthing connection? Inside adjacent appliances?
Even Martzloff warns about what protectors without earthing may be.

No earth ground means no effective protection. But those protectors
without earthing sell even for $100+ in Circuit City or Best Buy.
Clearly they must do something because they cost so much more? Those
who instead use science notice no dedicated earthing wire.
If the device has a 2 wire cord, no ground, and no other connections, is a
earth ground really necessary for protection of that device? A point of use
surge protector will limit the voltage going to the device. (The key is
that there are no other electrical connections to the device.) Relative to
ground, the device may see a large change, but since nothing on the device
is referenced to ground, the device see no destructive voltages. (Any
capacitative coupling is taken as insignificant in this case.)
 
w_tom wrote:

On Aug 30, 9:16 pm, craigm <n...@domain.invalid> wrote:
If the device has a 2 wire cord, no ground, and no other connections, is
a earth ground really necessary for protection of that device? A point of
use surge protector will limit the voltage going to the device. (The key
is that there are no other electrical connections to the device.)
Relative to ground, the device may see a large change, but since nothing
on the device is referenced to ground, the device see no destructive
voltages. (Any capacitative coupling is taken as insignificant in this
case.)

Ben Franklin's lightning was also finding earth ground via
something non-conductive - wooden church steeple. That same problem
exists inside a home. Things such as some wall paints, and linoleum
and concrete floors are even better conductors.

Why can a static electric discharge occur? Electric path is down an
arm, through something on the table top, and somehow into the rug to
charges beneath feet. How many of those items are wires? The house
is chock full of conductive items when we discuss surges.

Once permitted inside a building, then the surge will find numerous
paths to earth. Those many paths also explain why one appliance is
damaged while an adjacent appliance is unharmed.

Do we locate every conductive path in a room and conductive
materials inside walls? No. To create equipotential in one room, then
carefully integrate walls, floors, air ducts, and pipes all into the
protection system. No one will or is expected to do all that -
especially when one 'whole house' protector makes all that work for
every room unnecessary.

Make everything in the building equipotential. Create equipotential
by using earth beneath the building. Now all conductive materials in
the building are at near same voltages - no surge currents flow. Now
protection inside all appliances is not overwhelmed.

Yes, devices with multiple utility connections (portable phone base
station, cable modem, answering machine, dishwasher) are at greater
risk. Makes no difference if power cord is two wire or three wire (or
only one wire because switch is open). Anything that would protect on
that power cord is already inside those appliances. So that
protection inside all appliances is not overwhelmed, spend less money
for significantly superior protection. Earth one 'whole house'
protector, or earth cable TV and satellite dish wires using no
protector. Significantly better protection for tens of times less
money per appliance.

A surge approaching on a black wire is distributed to white and
green wires by an adjacent plug-in protector. Surge on all (two or
three) wires is still seeking earth ground. Incoming on AC electric
black wire, given more paths into stereo on black and white wires by
an adjacent protector, then out to earth ground via speaker wire
touching baseboard heater. Another example of damage because the
surge was permitted inside a building. The adjacent protector simply
gave that surge more wires to find earth ground via the stereo.

A lot of words, but none respond to my comments. Sure, a whole house
protector is a good idea, but that is not viable for everyone. (Think about
apartment dwellers or those who rent their home.)

For some folks, point of use protectors may be sufficient.

Point of use protectors also have value where a whole house protector is
being used.
 
w_tom wrote:

On Aug 31, 1:57 pm, craigm <n...@domain.invalid> wrote:
A lot of words, but none respond to my comments. Sure, a whole house
protector is a good idea, but that is not viable for everyone. (Think
about apartment dwellers or those who rent their home.)

For some folks, point of use protectors may be sufficient.

Where does a 'point of use' protector make that short connection to
earth? If a plug-in protector is protection, then your post makes
sense. However the protector is not protection. It is only a
connecting device to protection. Lots of word repeatedly demonstrate
why plug-in protectors would appear to be a complete solution but
don't even claim to be protection. It only claims to be a protector..
You sure can have fun with words and say nothing.

A MOV works by limiting the voltage between two nodes of a circuit. It does
nothing else. It does not know about 'ground' or 'earth'. Devices
connected to the nodes are protected from surges greater than the
specifications of the MOV. If the device connects to 2,3, 4, or 5 nodes in
the circuit, and all nodes are protected, then the device is protected.
(Within the limitations of the protection device, of course.)


In an apartment, modify a plug-in protector to act more like an
effective 'whole house' protector. First, cut its power cord as short
as possible. Every foot on that power cord means diminished
protection. Find a wall receptacle that is electrically closest to
the breaker box - minimum number of splices, shortest distance, etc..
Plug that 'short power cord' protector into that receptacle.
This does not provide useful protection as the protected nodes are where the
protector is. Any wiring between the node to be protected and the protector
defeats the protection. (As you appear to know.)

Hopefully a breaker box earth ground exists. What makes a protector
better? Increased distance between the protector and electronics.
Absolutely false. Disctance between the protector and the protected device
allows charge to be coupled into the connecting wire. What you suggest only
applies to surgest that come from the supply side of the {house, breaker
box, whatever].

This kind of a statement needs to be qualified w.r.t. the source of the
surge for it to have meaning.


Decrease a connection length to earth ground.

A protector without earth ground does nothing sufficient. It is
only a protector - a connecting device to protection. A protector
without connection to protection does nothing useful.
"Earth" is not protection. Numerous lightening victims connected to earth
were not protected.

Protection is keeping the voltages seen by the protected device to a
minimum.

"Earth" or "ground" becomes something else in the presense of a
surge. "Ground" does not revpresen an infinite volume of zero-voltage
space. Any grounding system is limited by the impedance to some arbitrary
reference point. If lightening hits the power lines entering a structure
ground potential can rise significantly inside the structure. However is
all the devices inside the structure only see the potentials the
protections devices allow to pass, damage is minimized.

A simple analogy is ESD packaging. Devices inside a sealed ESD bag are
protected from ESD as they can not see what goes on outside the bag. A
connection to "ground" is not required for this protection.




If a 'magic box' was sufficient, then it would claim such protection
in spec sheets. Why no such claim? Why is a 'magic box' that does
not even claim to provide protection also called sufficient?
For fun with words. Cute but meaningless.

The plug-
in protector without earthing is not sufficient for anyone. The
protector is only as effective as its earth ground. Or do we know it
is protection only because it is called a protector?
 
w_tom wrote:

On Sep 2, 8:27 pm, Jamie
jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
sorry, I don't want to get involved in your discussion but you could of
shorten that a bit!

Yes, but that means removing the many reasons why. Answers without
whys are akin to lies. We have a glorious president who demonstrated
same with WMDs.

Show me how we discuss protection without discussing energy? The
example is even Page 42 Figure 8 where 8000 volts was destructively
shunted (energy dissipated in) an adjacent TV. Why? Because the
protector limted voltage between some wires. Also notice important
numbers that are necessary - posted because craigm posts no numbers -
such as 250 to 900 volts - or what craigm calls voltage limiting.

Yes it is longer because it has numbers, defines details that craigm
ignored to obtain a bogus conclusion, and demonstrates the many other
facts that craigm forgot to provide.

How do we know he is posting half facts? He ignores Page 42 Figure
8 - those 8000 volts through an adjacent TV. He pretends there is no
energy to dissipate. He ignores the fact that a surge (voltage
limited or not) still seeks earth ground. And all that is paragraph
one - one some of the reasons why craigm has posted half facts and
erroneous conclusions.
As with others, you seem to attribute words to me that I didn't write.

The second TV is unprotected because of a poor installation. I am talking
about the successfully protected set.

You should not be trying to draw conclusions from what I don't say.

I'm done with this discussion.
 

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