Building Ground (long-...sorry)

[jakdedert]

I've read a good deal about the above. Ideally, the grounds for various
(telephone, cable, power) electrical utilities should all be common; and
the service entries for those sundry services should be located within
15' of each other.

If I ever build a new house, I will take that into account.

However, it's not practical at this time to realize the ideal. What I
have currently is as follows:

The phone drop (two lines) comes in on one side of the house and is
grounded to the water supply line which comes in the front of the house
(about of 20' of wire clamped to the pipe where it comes through the
foundation into the unfinished basement).

The power drop (100 amp 220v single-phase) enters at the back of the
house, about 30' diagonally from the phone service. A ground wire
snakes from the panel (inside a utility porch) around a couple of
corners and through the floor to a ground post of unknown length/depth
in the crawl space beneath the adjacent kitchen...approximately 20 feet
of wire with at least two 90 degree bends.

The cable drop is around 15' feet from the power service entrance, and
grounded to an adjacent outside faucet a couple of feet away (all
plumbing in the house is copper).

Over the years, we've had a good deal of surge and lightning related
damage to devices in the house...most recently a DSL modem.

Would I derive any advantage by driving a new ground post outside,
adjacent to the power drop and to run all the various service grounds to
it (around 15' for cable, 25' or so for phone)?

Alternatively, I could move the telephone ground wire to the existing
power drop ground post (probably using the same 20' wire), and also
extend cable ground to this point. That would give me a 'star'
configuration with all utilities having around 20'-30' of wire from each
drop to ground.

Moving the phone service drop at this time (the ideal) is not practical.

jak

 

[Dave Plowman (News)]

The phone drop (two lines) comes in on one side of the house and is
grounded to the water supply line which comes in the front of the house
(about of 20' of wire clamped to the pipe where it comes through the
foundation into the unfinished basement).

Could anyone explain why a US telephone cable needs a local ground? Aren't
they balanced?

The UK system only used a local ground for shared local lines which went
out years ago.

 

[Eric Law]

System is balanced and isolated in US too. The ground is just for surge / lightning protection.

Eric Law

 

[Michael Kennedy]

It is used for lightning protection.. Believe me you really need if you
happen to live in Florida.

- Mike

 

[Dave Plowman (News)]

System is balanced and isolated in US too. The ground is just for surge
/ lightning protection.

Right. Few telephone cables in the UK are overground, so that explains it.
The surge arrestor here is just wired between the incoming pair.

 

[Michael Kennedy]

hmm.. I can't say I know of many overground telephone wires in my area,
except in older houses that have overhead power service, they used to string
the telephone wire under the power wire, but the main phone lines are all
burried.

I found out the hard way that burrying the wire doesn't help with lightning
protection when I ran a cat5 ethernet wire from my house to a friends last
year. That thing got zapped evey time we had a bad storm..

- Mike

 

[Warren Weber]

It is used for lightning protection.. Believe me you really need if you
happen to live in Florida.

- Mike
OR Colorado WW

 

[Warren Weber]

It is used for lightning protection.. Believe me you really need if you
happen to live in Florida.

- Mike
OR Colorado WW

--

 

[Travis Jordan]

I found out the hard way that burrying the wire doesn't help with
lightning protection when I ran a cat5 ethernet wire from my house to
a friends last year. That thing got zapped evey time we had a bad
storm..

The problem wasn't caused by the ethernet wiring; it was the difference
in ground potential between the two homes.

You should have optically isolated the two ends to avoid the problem.

 

[Michael Kennedy]

No I'm not talking a small spark when you plug it in. I'm talking about
lightning hitting the wire during storms. It would arc off the wire when it
wasn't plugged into the arrestor.

- Mike

 

[w_tom]

Described by jakdedert is a building all but begging for lightning
damage. For example, a cow stands in an open field when lightning
strikes a nearby tree. The cow is killed. Killed by electromagnetic
fields? Of course not. Killed because cow was part of a path from
cloud, through tree, into earth to earth borne charges maybe miles
distant. The electrically shortest path was not under the cow. It was
up cow's hind legs and down fore legs. Cow was part of a direct
lightning strike from cloud to distant earthborne charges.

Cow could have lived is a halo ground surrounded the cow. That
buried conductor would have, instead, routed electricity around (not
through) cows. The concept is called single point earthing. Cow with
separated legs has multiple earthing connections - therefore dead. Cow
centered in a halo ground has a single point ground.

jakdedert describes here (and previously) utilities (ie mutli-line
phones) entering and earthed more like the cow. Building is even worse
because earthing points are farther apart. Destructive charge can
enter building on telephone line (overhead or underground line) either
from its grounding connection or via utility wire (from nearby struck
tree, from other struck building, or entering via ground rod). That
transient crossed building, destructively through appliances, to obtain
earth via AC electric.

Connecting phone line with a 20' plus ground wire or via pipes
accomplishes little. Wire has impedance. That means earthing from
each incoming utility to a single point earth ground MUST be less than
10 feet. Other features such as no splices, no sharp bends, no solder
joints (on wire or pipe), etc also required to lower impedance. Not
resistance - impedance.

A minimal single point ground is a grounding rod. That means even
incoming cable TV wire must make that 'less than 10 foot' earthing
connection to earthing electrode. Better earthing is a halo ground
(what saved the 'dead' cow) or even better, Ufer ground.

What does a protector do? A protector only connects from AC electric
or phone lines (that cannot be earthed directly) to an earthing
electrode. Protector is nothing more than an connection. No earth
ground means an ineffective protector - which many overpriced, plug-in
protector manufacturers hope you never learn. Plug-in protectors that
have no earthing connection, then, connect to what? They hope youj
never ask that question.

Cable TV does not need protectors which often degrade cable modem or
TV signal. Cable is earthed directly - hardwired - to earth without
any protector for superior protection. Wire does better than a
protector.

An electric utility demonstrates bad, good, and ugly earthing. Ugly
because the earthing electrode must be 'lengthened' so that all
utilities make a common earthing point:
http://www.cinergy.com/surge/ttip08.htm

Water pipe typically is not good earthing. Pipes too long, too far
away, too many sharp bends, solder joints, etc. A major difference
between earthing for human safety verses earthing for transistor
safety. A major difference between resistance and impedance means wire
distance is more critical that a low resistance ground. Worse,
jakdedert describes grounding to pipes or water faucets. That means
ineffective and multi point earthing - that also killed the cow.

Most critical component in a lightning protection system is earthing.
Earthing defines uality of that protection 'system' and effectiveness
of protectors. Ineffective plug-in protectors avoid all mention of
earthing to sell hyped products at higher profits. Such ineffective
products have no dedicated earthing connection AND avoid earthing
discussions to keep customers ignorant. Bottom line: a protector is
only as effective as its earth ground.

Effective protector manufacturers have names such as GE, Polyphaser,
Square D, Intermatic, Siemens, Cutler-Hammer, and Leviton. Their
effective products have that dedicated earthing wire.Notice that names
such as APC, Tripplite, Belkin, and Monster are specifically not
mentioned. The telephone company already installs an effective 'whole
house' protector in their NID (premise interface) box. But again, you
(the owner) define its effectiveness by providing an earthing system.

UK residents who suffer so few lightning storms also suffer frequent
and unnecessary damage. This because UK incoming phone lines don't
have that necessary earthing. BT does install effective earthed
protectors on their end. But subscribers are expected to pay for their
own protection - which is provided free in North America.

Also is a myth that underground wires are better protected. Does not
matter as demonstated by the 'dead' cow. Any utility that does not
first connect to single point ground before entering a building is an
obvious incoming path for household electronics damage. As the
'dead' cow demonstrates, single point earthing means even a nearby
lightning strike can be a direct strike into building electronics - if
building's earthing is not properly installed and connected to by every
incoming utility wire.

Damage could have been from voltage potential between different
buildings OR from buried wire carrying transient from a nearby struck
tree. Multiple sources of damage - all due to a building owner who did
not install the most critical component in a protection 'system':
single point earth ground. Why does a telco Central Office, connected
to every other building in town by copper wires, not suffer damage?
The solution has been standard for so many generations - proven
multiple generations before transistors were created. Protection is
and is defined by earthing. Even protectors are only as effective as
their earthing.

 

[jakdedert]

Described by jakdedert is a building all but begging for lightning
damage. For example, a cow stands in an open field when lightning
strikes a nearby tree. The cow is killed. Killed by electromagnetic
fields? Of course not. Killed because cow was part of a path from
cloud, through tree, into earth to earth borne charges maybe miles
distant. The electrically shortest path was not under the cow. It was
up cow's hind legs and down fore legs. Cow was part of a direct
lightning strike from cloud to distant earthborne charges.

Cow could have lived is a halo ground surrounded the cow. That
buried conductor would have, instead, routed electricity around (not
through) cows. The concept is called single point earthing. Cow with
separated legs has multiple earthing connections - therefore dead. Cow
centered in a halo ground has a single point ground.

jakdedert describes here (and previously) utilities (ie mutli-line
phones) entering and earthed more like the cow. Building is even worse
because earthing points are farther apart. Destructive charge can
enter building on telephone line (overhead or underground line) either
from its grounding connection or via utility wire (from nearby struck
tree, from other struck building, or entering via ground rod). That
transient crossed building, destructively through appliances, to obtain
earth via AC electric.

Yes, I've had problems which I have detailed here before. Still, the
above (and snipped portions) still beg the question: It's gonna be at
least 20 feet of copper between the service and ground. Still better to
single point? That's the 'hit' I'm getting....

Anything would be better than what we have, right? Upgrade the ground
conductor? I've read (here?) that 1/8" copper tubing is superior to the
(looks like) 12 ga. wire currently used in the phone and power grounds.

From the above, I'd assume that 'anything' I did to lower (and
equalize?) the impedance to ground would be--even though not ideal--at
least an improvement. How about multiple ground rods, one at each
service drop--connected together with the aforementioned tubing?

I know that if I could get the telco to drop the lines in between the
cable and power drops, the job would be significantly simplified...and
yes, I have a 100'+ oak tree within 20' of the house.....

jak

 

[w_tom]

'Tree' does not mean it must be a tree. Lightning could strike a
rock, a neighbor's house, a transcontinential pipe line, or even a
water box to create same effect. Earthing is the one solution always
required even if lightning strikes something distant or if lightning
strikes street utility wires.

Upgrade the ground conductor? I've read (here?) that 1/8" copper tubing
is superior to the (looks like) 12 ga. wire currently used in the phone and
power grounds.

Did you view 'bad, good, and ugly' figures from cinergy.com? That
earthing (in this case a 'right' solution) must conform to two masters.
One, for earthing transients (ie lightning). Two, to meet electrical
code defined in NEC Article 250 Section III (Artcile 250.50 through
250.70. Section III defines seven types of grounding electrodes and
numbers that apply including wire sizes.

For example, install a ground ring terminated by rod electrodes (8+'
copper clad steel rod). Since that ground ring has a ground rod where
each utility enters, then each utility can make a 'less than 10 foot'
connection to top of ground rod. Each rod is the same, large, single
point ground.

Code demands a ground ring be 2 AWG bare copper wire buried at least
30 inches. From your perspective, this so that ground wire is below
frost and remains in soil of constant humidity. Suggested is to obtain
of copy those five pages from an National Electrical Code book (maybe
in the library) to better appreciate what is required of each (of seven
type) electrodes.

Above to meet code. However grounding wires (to attach to that
single point ground) also must not have splices, no sharp bends, not
inside metallic conduit, routed away from all other non-earthing wires,
and must be firmly attached with proper connectors - for conditions
beyond what code requires. Best that all earthing wires remain
separate until all meet at the single point earth ground. Don't worry
about exceeding wire diameter. Worry more about wire length. Every
foot shorter than 10 feet means less electricity from lightning will
seek earth ground via household electronics.

Next part of that system would connect every wire from every incoming
cable to that earth ground. Telco has a protector from each (of two)
wires in cable to the ground wire. AC electric has three wires - only
one connects to earth directly. Therefore 'whole house' protector (see
manufacturer list that includes GE, Square D, etc) in AC mains box
connects other AC wires to that earthing wire.

Coax for cable TV and satellite dish use a ground block ($2 available
in Home Depot, Radio Shack, and Lowes) and 10 AWG wire for earthing.

 

[jakdedert]

'Tree' does not mean it must be a tree. Lightning could strike a
rock, a neighbor's house, a transcontinential pipe line, or even a
water box to create same effect. Earthing is the one solution always
required even if lightning strikes something distant or if lightning
strikes street utility wires.

<snip>

Thank you, Tom...I think. I'll have to reread your post several times
to get the gist of what you're saying. I'll also do some (more)
research and get the relevant parts of the Code.

'Tree' in this case does mean a tree...a big one, the highest single
point on my entire street...even though there are houses which sit
considerably higher than mine. This is one big tree...probably at least
part of the reason I seem to be plagued.

jak

 

[default]

I've read a good deal about the above. Ideally, the grounds for various
(telephone, cable, power) electrical utilities should all be common; and
the service entries for those sundry services should be located within
15' of each other.

If I ever build a new house, I will take that into account.

However, it's not practical at this time to realize the ideal. What I
have currently is as follows:

The phone drop (two lines) comes in on one side of the house and is
grounded to the water supply line which comes in the front of the house
(about of 20' of wire clamped to the pipe where it comes through the
foundation into the unfinished basement).

The power drop (100 amp 220v single-phase) enters at the back of the
house, about 30' diagonally from the phone service. A ground wire
snakes from the panel (inside a utility porch) around a couple of
corners and through the floor to a ground post of unknown length/depth
in the crawl space beneath the adjacent kitchen...approximately 20 feet
of wire with at least two 90 degree bends.

The cable drop is around 15' feet from the power service entrance, and
grounded to an adjacent outside faucet a couple of feet away (all
plumbing in the house is copper).

Over the years, we've had a good deal of surge and lightning related
damage to devices in the house...most recently a DSL modem.

Would I derive any advantage by driving a new ground post outside,
adjacent to the power drop and to run all the various service grounds to
it (around 15' for cable, 25' or so for phone)?

Alternatively, I could move the telephone ground wire to the existing
power drop ground post (probably using the same 20' wire), and also
extend cable ground to this point. That would give me a 'star'
configuration with all utilities having around 20'-30' of wire from each
drop to ground.

Moving the phone service drop at this time (the ideal) is not practical.

I'm assuming the DSL modem and computer are plugged into the same
outlet . . .

It sounds like you have two unknown grounds that are far from the
ideal. You don't say what the failure mode of the equipment is and
how severe - I'm guessing it is probably common-mode developing
between the two ground systems. If you get something like bridge
rectifiers in power supplies shorting - that could indicate a
differential voltage spike.

Or, better yet, start at the beginning . . .Check the power
transformer. There should be a lightning arrestor for the transformer
- a kind of insulator that sits off to the side of the can that is
clamped to the can and has a small 1/2"-1" air gap between it and the
HV terminal. (designs vary quite a bit but it should be there in some
form - a collection of broken porcelain around the base of the pole
and some carbon blocks means it is done its job once too often)

The transformer pole and transformer must be grounded. There should
be a thick soft copper wire running from the transformer down the
length of the pole and into the ground. Usually the wire is wrapped
in a spiral and nailed to the bottom of the pole.

Without the transformer grounded - anything you do may be wasted
effort. I had no problem getting a neighbor's lightening arrestor
replaced with just a call to the power company and, in another
instance, a pole ground wire replaced - they are subject to being
stolen by people trying to salvage the copper. Two different power
companies and no arguments - they just went out and fixed it.

Your best option is probably to get the grounds on the same circuit.
I'd sink a ground and wire to it, so I knew what its condition is
like. (ten foot length of half inch dia copper water pipe washed into
the soil is better than anything you're likely to drive into the
ground) Braze or solder the heavy wire on. Put it at the power
entrance as directly under the power meter as you can with no bends in
the heavy wire. Five or six feet to ground if you can manage it with
no bends. Use a large radius bend if you go around an obstacle. It
may not be practical, but do the best that the conditions allow.

What to do about the telephone line and power line separation? Sink
a separate ground for the phone line and just use it for the
lightening arrestor on the line and make sure it is bonded to the main
power ground. There was some good stuff in an ARRL article some years
ago that mentioned a similar problem. He solved it by adding a ground
for the phone line directly under the phone's entrance box to the
company supplied arrester then added a set of gas filled spark gaps in
addition to the arrester.

Cold water pipes are iffy - they can be excellent grounds or very poor
grounds. Too many variables - you'd have to know the material and
condition of the pipe, how straight the run to ground is, and what the
joints are like electrically. Some old systems used cast iron pipe
and the joints are not connected electrically. Some really old cities
still pull up a wooden water main from time to time . . . Galvanized
threaded joints are usually pretty good if the pipe was clean when the
pipes where joined and someone didn't get carried away with Teflon
tape.

Beyond that you can still get fancy with isolation transformers or
optical links.

 

[Bud--]

An excellent paper from the IEEE on surge and lightning protection
(which came from a w_tom post) is at;
http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf

Contrary to what w_tom says plug-in point-of-use surge protectors do
provide protection and are recommended in the paper above. All the
electrically interconnected apparatus, like tuner, amp, has to be
connected to the same surge protector. If there are external lines, like
cable TV, the apparatus can still be protected using a multiport plug-in
surge protector that, in addition to the power protection, has through
ports for the cable connection (and/or phone line, LAN connected to
devices not on the same surge protector, ...). Multiport surge
protectors, and how they protect, are described in the IEEE paper.

Another paper is from the NIST
http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf
It also recommends point-of-use plug-in surge protectors.

I agree with w_tom that single point grounding for wires entering a
building (also dish antenna) is a very good idea.

(A multiport surge protector provides a local single point ground at
protected equipment.(

For example, install a ground ring terminated by rod electrodes (8+'
copper clad steel rod). Since that ground ring has a ground rod where
each utility enters, then each utility can make a 'less than 10 foot'
connection to top of ground rod. Each rod is the same, large, single
point ground.

Why don't you get objectionable drop through the ground ring? (Not to
say that the ring isn't a good idea.)

When you talk about a "halo ground", as for your cow, I presume you are
talking about a ground ring. The only use of "halo ground" I have seen
is as in PolyPhaser papers - a conductive ring around a room
ceiling-wall edge, that may or may not be earthed, to counter the field
effects from the down current from a lightning strike on an adjacent
antenna tower.

If cable and power entrance points are separated, it would seem like the
cable could be wired from the its entrance ground block to a 2nd ground
block adjacent to the power service entrance, with a short connection
from the 2nd ground block to the power service grounding electrode
conductor. Cable distribution to the building from the 2nd ground block.
Similarly a secondary phone protector block could be installed adjacent
to the power service. I have never seen this suggested but it seems like
a practical way to get a single point ground.

bud--

 

[w_tom]

We had been through this before in alt.engineering.electrical. Those
who once strongly advocated 'point of use' protectors (ie ex-GE
employees) have backed off that recommendation. One example is an IEEE
paper by them about an "Upside Down House". Francois Martzloff and
Thomas Key in 1994 wrote in "Surging the Upside-Down House: Looking
into Upsetting Reference Voltages" :

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.

Why do those who once always advocated only 'point of use'
protectors now change their tune?

Effective protection at the appliance is already inside appliance.
If components inside 'point of use' or plug-in protectors were so
effective, then those $0.05 parts would already be inside each
appliance. Once they were installed. But since those parts (currently
inside plug-in protectors) were not effective inside appliances, then
appliance manufactures use only other well proven techniques
internally.

This internal appliance protection assumes a transient will be
earthed before entering a building. That being the purpose of a 'whole
house' protector that also costs tens of times less money per protected
appliance. If not earthed, then a transient can overwhelm protection
inside appliances. As Martzloff, et al noted, excessive voltage can
occur even "perhaps because, surge protective devices are present at
the point of connection of appliances". Martzloff was once a major
promoter of 'point of use' protectors.

Do we spend $20 to protect every appliance - or do we spend far less
money to enhance earthing? Per dollar, earthing provides major
appliance protection. Point of use protectors - if for no other reason
- cost massive dollars and provides little benefit. Again, if it were
effective, then those same parts costing so little (and selling at
exaggerated profits) would already be inside appliances. Shunt mode
protectors are only as effective as their earth ground. Plug-in
protectors have what for earthing? So instead, plug-in manufacturers
forget to mention earthing (since earthing is not provided by plug-in
protectors) AND forget to mention protection already inside appliances.
Profits are just too large to be fully honest. Protection is
earthing.... the most critical component in every protection 'system'.

How does a shunt mode protector do anything effective when it does
not shunt to earth? Manufacturer hopes we don't ask that question.
Plug-in protector manufacturers, instead, cite protection from
transients that don't typically cause damage - and hope you don't
notice. They hope you never learn why earthing is so critical -
profits being too outrageously high to be fully honest. Even those who
once only recommended 'point of use' protectors are now changing their
tune in IEEE papers - citing advantages of 'whole house' protectors -
that also cost tens of times less money per protected appliance.

Why would an objectionable voltage not exist in a ground ring? Well
repeatedly cited cinergy.com citation shows a bad, good, and ugly
solution. The prefered solution puts everything at a single point.
But the OP does not have every utility approaching a single point.
Therefore an uglier solution is useful. That solution does make the
earthing more conductive. It does provide a single point ground. It
is a major improvement over what he currently has. Others who can plan
a new house must avoid what the OP has - before footing are even
poured. What the OP currently has would explain (and may be reason
for) his many years of electronics damage. Provided is an effective
and easier solution - since utilities don't like changing services
without big buck bills.

 

[Bud--]

We had been through this before in alt.engineering.electrical. Those
who once strongly advocated 'point of use' protectors (ie ex-GE
employees) have backed off that recommendation. One example is an IEEE
paper by them about an "Upside Down House". Francois Martzloff and
Thomas Key in 1994 wrote in "Surging the Upside-Down House: Looking
into Upsetting Reference Voltages" :

This is exactly what a multiport plug-in point-of-use surge protective
device protects against. These are called Surge Reference Equalizers by
the IEEE. Another paper specifically about SREs is
http://www.eeel.nist.gov/817/817g/spd-anthology/files/SRE link. pdf
This paper is currently available from the NIST in a collection with a
forward by your good buddy François Martzloff (who was an author of this
paper).

I have provided links to an IEEE paper and and 2 NIST papers, all
current, that recommend plug in surge protectors. In previous threads
(and this one) I have not seen any links supporting your view. Its you
against the IEEE and NIST (and a lot of other people).

bud--

 

[w_tom]

Or, better yet, start at the beginning . . .Check the power
transformer. There should be a lightning arrestor for the transformer
- a kind of insulator that sits off to the side of the can that is
clamped to the can and has a small 1/2"-1" air gap between it and the
HV terminal. (designs vary quite a bit but it should be there in some
form - a collection of broken porcelain around the base of the pole
and some carbon blocks means it is done its job once too often)

The transformer pole and transformer must be grounded. There should
be a thick soft copper wire running from the transformer down the
length of the pole and into the ground. Usually the wire is wrapped
in a spiral and nailed to the bottom of the pole.

Without the transformer grounded - anything you do may be wasted
effort. I had no problem getting a neighbor's lightening arrestor
replaced with just a call to the power company and, in another
instance, a pole ground wire replaced - they are subject to being
stolen by people trying to salvage the copper. Two different power
companies and no arguments - they just went out and fixed it.
...

Default makes an important point. Defined for a house is a 'whole
house' protection system - also called secondary protection. Primary
protection is provided by the utility, as default has described.
Pictures that demonstrate inspection of a Primary protection system:
http://www.tvtower.com/fpl.html

 

[w_tom]

In Bud's cited 1993 paper on 'surge reference equalizer' or
'multiport protector', Martzloff, et al defines a problem common in
most residences where traditional plug-in (point of use) protectors are
used:

Figure 2 shows such an arrangement, where the telephone
port of the Fax machine is assumed by the end-user to be
protected, thanks to the Network Interface Device (NID)
installed by the telephone company, and the power port is
also expected to be protected by the plug-in surge-protective
device installed by the surge conscious end-user. ...

IOW power strip protector simply creates one of many defined
transient problems that contribute to electronics damage:

A difference of voltage appears across the two equipment ports
during the surge event, in particular during the rise time. This
difference of voltage can cause an upset or hard failure if the
equipment has not been specifically designed for that stress.
Thus, separate, uncoordinated protection of each of the two
ports can still leave the equipment at risk.

Suggested by that 1993 paper is a multi-port protector - surge
reference equalizer- that only uses a principle called equipotential.
First, $20+ to protect only one appliance; without conductivity to
earth?

Second, defined are six ports that must be part of equipotential.
A multiport protector must provide equipotential for all ports at a
point inside the room. But as posted back in April - it does not
provide equipotential because some ports are not part of that
equalization technique. Where is concrete floor or linoleum tile
included as part of multiport protection? Where are baseboard heat,
air ducts, wall paint, or furniture included? That paper calls them
'enclosure ports'. Any one port not part of a multiport equalizer
means equipotential is compromised.

To have equipotential inside a room means the entire room must be
constructed to provide equipotential. Therefore we locate
equipotential where equipotential is easy to achieve.

And third, protection must provide both equipotential and a
conductive path to earth. Since neither equipotential nor conductivity
alone is sufficient, then a protection 'system' must do both. That
'point of use' protector provides all but no conductivity - no
effective earthing.

Not only is equipotential compromised in a room not constructed to
provide equipotential. Also the 'system' does not provide necessary
conductivity to earth. All this and $20 or $80 to ineffectively
protect one appliance? How is that effective?

Meanwhile his 1993 paper then moves on to describe another protective
solution:

High-current surges on the power system originating
outside of the user's premises, associated with
lightning or major power-system events, are best
diverted at the service entrance of the premises.
While such a protection is not mandated at present,
trends indicate growing interest in this type of surge
protection. Either the utility or the end-user may provide
a high energy surge arrester at the service entrance.

Described is a 'whole house' protector. Note how it is described:

... are best diverted at the service entrance of the premises.

'Best' protector recommended by Bud's 1993 paper costs about $1 per
protected electronics. It does provide equipotential to every room (by
making the equipotential point beneath the entire house rather than a
point inside one room). And it provides a best conductivity to earth.
Both requirements - equipotential and conductivity - are necessary for
a 'best' solution. Surge reference equalizer ... AND more ... that
is provided for a whole building rather than just for one appliance is
called 'whole house' protection. As that 1993 paper notes, part of
that 'whole house' system is already in telephone NID.

The same author later states in a 1994 paper:

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.

Curiously, this interest in a 'whole house' solution coincided with
post 1990 National Electrical Code changes that require earthing an AC
mains breaker box and all other incoming utilities to a common point.
A common earthing point that must be adjacent - a short distance.
Although code is only for human safety, still, those changes make
'whole house' protection more effective and simpler to install. To
provide surge reference equalization - AND more.

What does not change? A protector - the protection 'system' - is
only as effective as its earth ground. A fundamental demonstrated by
IEEE papers cited in that previous April discussion.

The OP (jakdedert) suspects years of electronics damage due to
transients. His earthing system is defined as defective. Earthing
that violates principles of single point earth ground and post 1990
code. Provided were examples from a utility (cinergy.com), further
details in how to create single point earthing for that building, AND
how to connect each utility to that earthing. Connections either by
hard wire or by effective protectors that even cost less - 'whole
house' protectors. Conductors for earthing and those 'whole house'
protectors are even sold in Lowes, Home Depot, and electrical supply
houses. A solution even recommended in Martzloff's 1993 paper and a
following 1994 IEEE paper. A solution that is routine in virtually
every telephone switching station, commercial broadcasting, emergency
response centers, and now in homes constructed to protect household
transistors.