Surge Protectors

[Jeffrey D Angus]

I just checked, and its difficult to find surpressors that
are cheap. I found one for $30 and might get a discounted
price. This is a basic model..................
http://www.grainger.com/Grainger/items/1ECD1?Pid=search

Well, you can't say inexpensive and Grainger in the same sentence.
You'll find the exact same products elsewhere for 25-50% less.

Jeff

 

[bud--]

GregS wrote:

I wouldn't call $30 for a service panel suppressor expensive. The 2
plug-in suppressors I am using cost about $30 each. You appear to be
looking for Cydrome's "cheap-o" suppressors.

The IEEE surge guide recommends - for homes - ratings of 20-70kA, or for
high lightning areas 40-120kA. All the MOVs in the 2 plug-in
suppressors I have are rated higher than the Grainger suppressor. I have
never heard of ICM.

I always thought local surpressors were good to protect from motorized equipment
and keep things common mode and to ground.

Motors are not a particular surge threat in a home. The #1 hazard is
lighting. The #2 threat is normal and abnormal utility switching
operations, including switching power factor correction capacitors.
Equipment, in general, has somewhere over 600-800V immunity from surges
(from Martzloff).

I might have a lack of available breakers, and I am thinking I
allready have an outlet near the box on one 120 side. i might put in another outlet on the other
120 side and use plug in replacable MOV's. I don't see much difference in
using separate breakers vs protecting lines allready in use.

If I am reading you right, you want to protect the service with plug-in
suppressors. Bad idea. I wrote earlier that the impedance of wire at
surge frequencies greatly limits the current. There is a high voltage
drop along the wire. The clamp voltage at the panel will be far higher
than the voltage at the suppressor. This is also an issue for panel
mounted suppressors. See the section on lead length in the IEEE surge
guide starting pdf page 31.

If plug-in suppressors have a very short branch circuit length to the
panel they should have high ratings.

I believe at least some service panel suppressors say to wire them to
existing circuits/circuit breakers.

 

[Grant]

westom (aka w_tom) is a well known internet nut on a religious crusade
to eliminate the scourge of plug-in suppressors. He is here because he
uses google groups to look for "surge".

As I said previously (and westom conveniently did not include), UL
requires that suppressors - plug-in and service panel - be fully
functional after a series of 20 test surges. They can fail only during
later tests that determine they fail safely.

Do they fail to known state? Open or short? App. note showed a test
rig with individually fused varistors, so I'm thinking they fail shorted?

Grant.

 

[GregS]

I wouldn't call $30 for a service panel suppressor expensive. The 2
plug-in suppressors I am using cost about $30 each. You appear to be
looking for Cydrome's "cheap-o" suppressors.

I said I found a cheap one.
I found another model with a lot higher rating. Most surpressors sold are almost $200.
It seems while searching, there is a trend to upgrade to higher current ratings.

But, a little Tripplite portable laptop surpressor has a really
high rating in Joules. ??

http://www.amazon.com/Tripp-Lite-TRAVELER-Suppressor-Transformers/dp/B00006B83F

 

[bud--]

Do they fail to known state? Open or short? App. note showed a test
rig with individually fused varistors, so I'm thinking they fail shorted?

Normal failure mode is that as MOVs deteriorate (past the defined end of
life) the voltage at which they start to conduct goes down until they
conduct on 'normal' voltage. That produces heat and they go into thermal
runaway and wind up as a low resistance or short. I would expect this is
after (not during) a surge. The thermal disconnects required in UL1449
listed suppressors disconnect MOVs when they fail. If this is a fuse I
would expect it is in close proximity to the MOV.

The IEEE surge guide shows that for plug-in suppressors, the protected
load can be connected across the MOVs, and be disconnected if MOVS fail.
Or the protected load can be connected to the incoming line and remain
powered if the MOVs are disconnected. I want the former.

 

[GregS]

How many hundred joules? Destructive surges are hundreds of
thousands of joules. How does that Tripplite magically make all that
energy disappear? It doesn't. That $3 power strip with some ten cent
protector parts is selling for how much? Appreciate its purpose.

Go to Lowes. Ask him for the Cutler-Hammer 'whole house' protector
that costs less than $50. That protector (model CHSPMICRO) is for
50,000 amp surges. Don't take my word for it. Read the numeric
specs. It will connect a direct lightning strike harmless to earth if
connected to a breaker box that connects 'less than 10 feet' to earth
ground. Massive energy dissipates harmlessly in earth. That Cutler-
Hammer protector is required to protect the Tripplite.

It is always about where energy dissipates. Why does that Tripplite
numeric specifications not list protection from each type of surge -
in numbers? Because it only claims to protect from surges that are
typically not destructive. How does its hundreds of joules absorb
surges that are hundreds of thousands of joules? Ask bud for those
specs that claim protection from each type of surge. He will never
provide those specs.

A protector is only as effective as its earth ground. Which is why
the Cutler-Hammer protector - about $1 per protected appliance - is
also the superior solution

OK, I can't find it on their website.

Read here. You say hundreds of thousands of Joules.
This one has 100KA at 840 Joules

This is twice the amperage as you state.

http://www.drillspot.com/products/423212/Supco_SCMPLUS_Surge_Protector

grge

 

[GregS]

OK, I can't find it on their website.

Read here. You say hundreds of thousands of Joules.
This one has 100KA at 840 Joules

The little bitty Tripplite laptop protector is over a 1000 Joules.

 

[bud--]

How many hundred joules? Destructive surges are hundreds of
thousands of joules.

So service panel suppressors absorb hundreds of thousands of joules?

How does that Tripplite magically make all that
energy disappear? It doesn't.

Of course not.

As explained early in this thread, the amount of energy that can reach a
plug-in suppressor is surprisingly small. The information came from
Martzloff, the NIST expert on surges.

That $3 power strip with some ten cent
protector parts is selling for how much?

One of the suppressors I use has 3 MOVs with ratings of 590J each.
Provide a source for a 590J MOV for $.10.

Go to Lowes. Ask him for the Cutler-Hammer 'whole house' protector
that costs less than $50.

Last I heard this didn't exist. Apparently Greg couldn't find it either.

Why does that Tripplite
numeric specifications not list protection from each type of surge -
in numbers?

Why does service panel suppressor manufacturer SquareD not list "each
type of surge in numbers"? Because it is nonsense - just another bogus
argument. UL listed suppressors have MOVs from H-N, H-G, N-G. That is
all possible combinations and all possible surges.

How does its hundreds of joules absorb
surges that are hundreds of thousands of joules?

How does "hundreds of joules absorb surges that are hundreds of
thousands of joules" in a service panel suppressor? It doesn't. Neither
service panel or plug-in suppressors protect by absorbing energy. They
absorb some energy in the process of protecting.

Ask bud for those
specs that claim protection from each type of surge. He will never
provide those specs.

I have provided specs often, so have others. They are always ignored by
westom, who just continues to repeat his lies.

A protector is only as effective as its earth ground.

The religious (immune form challenge) belief in earthing.

Why aren't flying airplanes crashing every day when they are hit by
lightning? Do they drag an earthing chain?

Still missing - 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"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?
- Why don’t favored SquareD service panel suppressors list "each type of
surge"?

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[bud--]

Bud's job is
to promote plug-in protectors.

Lacking any valid technical arguments westom attacks those who challenge
his nonsense.

So he will say anything to avoid that
reality.

westom will say anything to avoid the reality that plug-in suppressors
are effective.

The IEEE, NIST, General Electric, Siemens, Leviton, Intermatic, Keison,
and Square D all say they are.

Every responsible source discusses earth as the means of
eliminating those voltage differences.

It is the religious belief (immune from challenge) in earthing.

Everyone is in favor of earthing.

And every responsible source says plug-in suppressors are effective.

The IEEE surge guide explains, for those that can think, that plug-in
suppressors work primarily by clamping the voltage on each wire to the
ground at the suppressor, not earthing. The IEEE says earthing occurs
elsewhere in the system.

To do that means the protector must connect even direct lightning
strikes harmlessly to earth. To connect 20,000 amps (a typical
lightning strike) harmlessly to earth means, at minimum, a 50,000 amps
protector. At 24,000 amps, you would need two of those Grainger
protectors just to do a minimum.

A 20,000A direct lightning strike to a power line will have multiple
paths to earth. The maximum surge current to a house from a much more
powerful lightning is 10,000A according to accepted standards.

The IEEE surge guide recommends - for homes - ratings of 20-70kA, or for
high lightning areas 40-120kA.

westom, of course, is smarter than the IEEE.

More responsible companies make these 'whole house' protector
including General Electric, Siemens, Leviton, Intermatic, Keison, and
Square D.

All these "responsible companies" except SquareD make plug-in suppressors.

SquareD says for their "best" service panel suppressor "electronic
equipment may need additional protection by installing plug-in
[suppressors] at the point of use."

Surges created by motors
are the myth that Bud promotes

westom is prone to hallucinations. "Motors are not a particular surge
threat in a home."

Ask bud for the manufacturer spec that claims protection from
each type of surge. He works in this business.

The lie repeated - 2nd time.

UL is only about human safety. Says nothing about whether a
protector is effective.

Nonsense. As has been detailed previously, a UL listed suppressor has to
suppress a series of surges and remain functional.

He will not even admit he is paid to promote plug-
in protectors - ie that Tripplite.

The lie repeated - 3rd time.

What will that Tripplite do when its hundreds of joules somehow
absorbs surges that are hundreds of thousands of joules? Explode.
Vaporize. Create a human safety problem also seen in these other
scary pictures:
http://www.hanford.gov/rl/?page=556&parent=554

In addition to completely failing to understand how any suppressor
works, westom refuses to understand his own hanford link. It is about
"some older model" power strips and says overheating was fixed with a
revision to UL1449 that required thermal disconnects. That was 1998.
There is no reason to believe, from any of these links, that there is a
problem with suppressors produced under the UL standard that has been in
effect since 1998. None of these links even say a damaged suppressor had
a UL label.

But with no valid technical arguments all westom has is pathetic scare
tactics.

Bud's job is to keep you from learning these realities.

The lie repeated - 4th time.

Plug-in protectors (ie that Tripplite) require
protection that only earthing and the 'whole house' protector can
provide.

Funny - neither the IEEE or NIST surge guides mention that.
Another of westom's hallucinations

Yes, to do what bud is claiming,
you must buy at least 20 plug-in protectors for all over house.

Yet another hallucination.

Did bud forget to mention what his job is?

The lie repeated - 5th time. People with valid arguments don't have to lie.

Still missing - any source that agrees with westom that plug-in
suppressors are NOT effective.

Still missing - 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"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?
- Why does "responsible" manufacturer SquareD says "electronic
equipment may need additional protection by installing plug-in
[suppressors] at the point of use"?

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[bud--]

How does it fail? Open - sometimes explosively.

They fail shorted. If not removed from a supply of power they may fracture.

A thermal fuse
disconnects its protector circuit. Leave the appliance connected to
that surge – to fend for itself.

As pointed out previously, in a plug-in suppressor the protected load
may be connected across the MOV and be disconnected with a failing MOV.

If a service panel suppressor fails it leaves the appliance connected to
surges – to fend for itself.

Earth
one 'whole house' protector so that energy dissipates harmlessly in
earth.

A service panel suppressor is a good idea.

But repeating from NIST surge guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

A service panel suppressor does not limit the voltage between power and
cable/phone wires, which the NIST surge guide suggests is the cause of
most equipment damage.

A protector is only as
effective as its earth ground.

westom's religious mantra protects him from confusing thoughts - like
plug-in suppressors work primarily by clamping, not earthing.

Still missing - any reliable source that agrees with westom that plug-in
suppressors are NOT effective.

Still missing - 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"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[bud--]

[email protected] (GregS) wrote in

Ratings are good. I wouldn't buy it because I have never heard of the
manufacturer. I would like to explicitly see that it is UL1449 listed.
"Meets UL" is a manufacturer claim and is not the same as UL listed (UL
tested). The "UL 1449 Clamping Volts" have nothing to do with UL ratings
- a red flag.

surge protectors don't ABSORB strike energy,they shunt it to
ground,providing a low resistance path to ground.
Instead of the energy passing thru your equipment on it's way to ground.

That is probably appreciated by people here, but not in general. Neither
service panel suppressors or plug-in suppressors protect by absorbing
the surge. But they both absorb some energy in protecting.

A higher Joules rating means the device absorbs less than a lower rated
device,and thus can divert more energy before IT blows up.

The energy rating of a MOV - say 100 joules - is the singe event energy
that can be absorbed by the MOV and put it at the defined end of life
(but still functional). If the energy hits are less, say 10 joules, the
cumulative energy rating will be significantly higher than 100 joules.
If the energy hits are far lower, say 2 joules, the cumulative energy
the MOV can absorb will be far larger than 100 joules. A very high
rating means the suppressor is far less likely to fail. I don't expect
my plug-in suppressors with high ratings to ever fail.

One more limit is your home wiring;how much strike energy can those lines
carry? (to ground)

and how good is the house ground?

If a house has a surge current to earth of 1,000A and a quite low
resistance to earth of 10 ohms the system ground will rise to 10,000V
above "absolute" earth potential.

Martzloff 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." Make sure the phone and cable
entrance protectors are connected with short wires to the ground at the
power service. (Other systems, like satellite must also be connected.)
If they are, the power and phone and cable wires can rise together. IMHO
'improving' the earthing is less important.

High voltage between power and phone/cable wires is likely a major cause
of equipment damage.

 

[bud--]

Why do telcos all over the world not waste money on plug-in
protectors?

Gee - why wouldn't telcos use plug-in suppressors for their switches? Um
- one reason may be because the switches are high amp hard wired and the
thousands of phone circuits would have go through the suppressor?

A protector is only as effective as its
earth ground.

The required religious mantra along with the drivel that has already
been debunked. westom is a fan of Josef Goebbels and thinks if you
repeat a lie often enough, people will believe it.

But - surprise - still no reliable source that agrees with westom that
plug-in suppressors are NOT effective.

And surprise - still missing, answers to any of the 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"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?
- Why aren't airplanes crashing daily when they get hit by lightning (or
do they drag an earthing chain)?
- Why does "responsible" manufacturer SquareD says "electronic
equipment may need additional protection by installing plug-in
[suppressors] at the point of use"?
- Why don’t favored SquareD service panel suppressors list "each type of
surge"?

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[bud--]

So he now wants to discuss airplanes..

westom still refuses to explain how you can protect airplanes without an
earth connection. What a surprise.

Why are flying airplanes relevant?

"A protector is only as effective as its earth ground."

If you could figure out how airplanes are protected you could figure out
how plug-in suppressors work.

In deperation, he will discuss a flying airplane.

In desperation westom will ignore the question.

Where are those numeric specs that claim protection from each type
of surge. Bud cannot provide them for one simple reason.

Each type of surge is still nonsense. And westom has never explained how
common mode surges get past the neutral-ground bond required in all US
services.

Just a few of the times specs have been provided:
<http://groups.google.com/groups/sea...++joules+author:bud--&btnG=Search&sitesearch=>

westom will continue to lie about them just like he has every time in
the past.

Numerous IEEE Standards say why bud's protectors do not claim
protection in their numeric specs. From the IEEE Red Book:

The IEEE Emerald book ("IEEE Recommended Practice for Powering and
Grounding Sensitive Electronic Equipment"), an IEEE standard, recognizes
plug-in suppressors as an effective protection device. This is the most
appropriate IEEE standard for protecting electronics.

And the IEEE surge guide, which was published by the IEEE, says plug-in
suppressors are effective.

A protector is only as effective as its earth ground.

Ho-hum - the required religious mantra.

Still no reliable source that agrees with westom that plug-in
suppressors are NOT effective.

Still missing, 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"?
- Why does the NIST guide say "One effective solution is to have the
consumer install" a multiport plug-in suppressor?
- How would a service panel suppressor provide any protection in the
IEEE example, page 42?
- Why does the IEEE guide say for distant service points "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector"?
- Why did Martzloff say in his paper "One solution. illustrated in this
paper, is the insertion of a properly designed [multiport plug-in surge
suppressor]"?
- Why does Dr. Mansoor support multiport plug-in suppressors?
- Why aren't airplanes crashing daily when they get hit by lightning (or
do they drag an earthing chain)?
- Why does "responsible" manufacturer SquareD says "electronic
equipment may need additional protection by installing plug-in
[suppressors] at the point of use"?
- Why don’t favored SquareD service panel suppressors list "each type of
surge"?

Why can't you answer simple questions westom???

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[bud--]

That is not what your protectors do. Others can observe same. A
power strip protector with the 'failed' light on still power
appliances.

With minimal reading ability westom could read in the IEEE surge guide
the discussion on connecting the protected load across the MOVs. At
least one, and probalby both, of the suppressors I have do that.

Or view pictures from Zerosurge:
http://www.zerosurge.com/HTML/movs.html
They removed all MOVs.

This is indeed a problem if there is a gang of MOV thieves operating in
your neighborhood. Check with your local police.

The NIST
calls them "useless".

If the village idiot was not wearing religious blinders he could read
what the NIST surge guide says:
They are "the easiest solution".
And "one effective solution is to have the consumer install" a multiport
plug-in suppressor.

Necessary even to protect protectors that bud promotes.

I promote only accurate information - like the IEEE and NIST surge guides.

westom promotes his religious beliefs. Just like talking to Jehovah’s
Witness.

bud will post incessently.

westom will post incessantly. His belief in earthing has been challenged
and cracks in his universe may develop.

And never provide one simple fact.

Facts I have provided:
- The only 2 examples of protection in the IEEE guide use plug-in
suppressors.
- The NIST guide says plug-in suppressors are "the easiest solution"
- The NIST guide says "One effective solution is to have the consumer
install" a multiport plug-in suppressor.
- A service panel suppressor would provide no protection in the IEEE
example, page 42.
- The IEEE guide says in one example "the only effective way of
protecting the equipment is to use a multiport [plug-in] protector".
- Martzloff says in a paper "One solution. illustrated in this paper, is
the insertion of a properly designed [multiport plug-in surge suppressor]".
- Dr. Mansoor supports multiport plug-in suppressors
- SquareD says "electronic equipment may need additional protection by
installing plug-in [suppressors] at the point of use".
- SquareD service panel suppressors do not list "each type of surge".


And the biggest fact:
westom has never provided a source that agrees with him that plug-in
suppressors do NOT work.

For real science read the IEEE and NIST surge guides. Both say plug-in
suppressors are effective.

 

[Jeffrey D Angus]

westom is a fan of Josef Goebbels and thinks if you
repeat a lie often enough, people will believe it.

Oopsies, thread over. Due to my invoking of Goodwin's Law.

Jeff

 

[Jeffrey D Angus]

isn't it Godwin's Law? (DAGS)

Yeah, my fingers are either getting fatter or my keyboard's
getting narrower.

Jeff

 

[Cydrome Leader]

How many hundred joules? Destructive surges are hundreds of
thousands of joules. How does that Tripplite magically make all that
energy disappear? It doesn't. That $3 power strip with some ten cent
protector parts is selling for how much? Appreciate its purpose.

Go to Lowes. Ask him for the Cutler-Hammer 'whole house' protector
that costs less than $50. That protector (model CHSPMICRO) is for
50,000 amp surges. Don't take my word for it. Read the numeric
specs. It will connect a direct lightning strike harmless to earth if
connected to a breaker box that connects 'less than 10 feet' to earth
ground. Massive energy dissipates harmlessly in earth. That Cutler-
Hammer protector is required to protect the Tripplite.

It is always about where energy dissipates. Why does that Tripplite
numeric specifications not list protection from each type of surge -
in numbers? Because it only claims to protect from surges that are
typically not destructive. How does its hundreds of joules absorb
surges that are hundreds of thousands of joules? Ask bud for those
specs that claim protection from each type of surge. He will never
provide those specs.

A protector is only as effective as its earth ground. Which is why
the Cutler-Hammer protector - about $1 per protected appliance - is
also the superior solution.

bingo.

I'm still amused that people really believe bogus junk surge protector
power strips from china are actually made to any relevant UL rating of any
sort.

 

[Cydrome Leader]

The little bitty Tripplite laptop protector is over a 1000 Joules.

you really think so?

send one over to me, I'll post a video of me dumping 1kJ into to to see
what happens.

 

[bud--]

bingo.

I'm still amused that people really believe bogus junk surge protector
power strips from china are actually made to any relevant UL rating of any
sort.

"People" - like the 6 electrical engineers that actually work at surge
protection?
Who say in a surge guide from the IEEE that plug-in suppressors are
effective?
And in a surge guide from the NIST that plug-in suppressors are effective?
Do you know of more reliable sources than the IEEE and NIST?

And you still haven't admitted that UL tests the devices it lists?

Still missing - your source that says plug-in suppressors are NOT
effective - just like westom.
And westom has been looking for years.

I can only conclude that you are a Nazi.

 

[William Sommerwerck]

It is bud's job to constantly promote lies and myths. He is paid

to promote plug-in protectors. Lying is what promoters may do.
Where are those numeric specs? bud will never provide any.
He cannot claim protection that does not exist.

Where does that energy dissipate? bud cannot say. Otherwise
he must admit that plug-in protectors are profit centers – not
protection.

Uh... In the MOV?

I thought the MOV conducted above its breakdown voltage (generally around
300V), and the energy in the section of the AC waveform above that voltage
heated up the MOV.

Am I missing something?

Many years ago, PC and/or Byte (I forget which) used to test suppressors. If
they failed to provide suppression, I assume the mag would have said so.