Re: belkin power conditioner for my Samsung LCD - is it worth it???

Appreciate the characteristics of electricity. For example, connect
a radio directly to earth ground and receive no (or diminished) radio
signals. Connect a long wire to that radio and earth that far end.
Get strong radio signals. Why is that earth ground far down the wire
not same as a short earthing connection to the same radio antenna?
Because various electrical parameters causes electricity to act
differently even on the same wire.

Appreciate why lightning strikes a chimney or wooden church
steeple. Neither is electrically conductive. Both are quite
conductive to lightning. Again, change electrical parameters and
suddenly something becomes conductive.

Let's take that wall receptacle safety ground. 50 feet back to
breaker box is maybe 0.2 ohms resistance - a near short circuit. That
same wire carrying a surge may be 120 ohms impedance. Again, same
wire. But with different electrical parameters, the same wire is very
conductive to 60 Hz electricity and not very conductive to much higher
frequencies in lightning.

One of the best earthing electrodes is rebar inside concrete
footings. How can this be? Concrete is not a conductor of
electricity. Well, yes it is to lightning which is why Ufer grounds
were first used so that ammunition igloos could suffer direct
lightning strikes without damage.

Above is about how wire length is relevant for surges and not so
relevant to AC electric. The more important wire characteristic for
grounding AC electric is wire diameter. More important parameter for
earthing lightning is wire length (and other things such as no sharp
bends, not inside metallic conduit, no splices, etc.

Now to discuss grounding. Well your computer has a motherboard
ground which is different from chassis ground, which maybe different
from analog ground on a peripheral board, which is different from AC
receptacle ground, which is different from ground inside the TV, which
is different from that safety ground bar inside a breaker box which is
different from your building earthing electrode, which is electrically
different from that ground at the utility pole transformer. Most (not
all) of these grounds are interconnected. All are electrically
different. For example, if computer motherboard ground connects,
eventually, to building earthing electrode, then a lightning rod can
be grounded via the motherboard? Of course not. But that would be
true if wires were perfect conductors.

Earth ground is a unique ground - the ground so important for surge
protection. Take a $5 three light receptacle tester. It can detect a
connection to safety ground inside a breaker box. It says nothing
about another ground - earth ground. With one wire to earth ground
and no return wire, then how can that ground be electrically tested?
Well many assume all grounds are same; therefore falsely assume that
three light tester also tests earth ground. That is a problem with
grounding. They are all different. They are all grounds. But each
is uniquely defined by what electricity is being grounded.

Electricity is always different at two ends of a copper wire.
Sometimes that difference is so trivial that we call it a short
circuit. But when discussing a wire to radio antenna or when
discussing the earthing of lighting, then grounds at both ends of that
same wire are significantly different. Two interconnected grounds
are different when electricity is different at both ends of the wire.

We install earth ground for multiple reasons. Earthing is required
for human safety so that a fault will trip a circuit breaker. Same
ground may also eliminate noise problems. And same earth ground is
enhanced for earthing surges - transistor safety. Whereas we ground
to meet code (human safety), that same ground also performs other
tasks not required by code. Code does not define transistor safety.

Not only are all those interconnected grounds different. For surge
protection, the building's earth ground must be a common ground to all
incoming utilities.

Well I could continue. But for a primer discussion, already are
many new concepts.

Above discusses the why? Another post discusses the 'hows' of
earthing for surge protection in comp.sys.mac.comm on 4 Jul 2007
entitled "DSL speed" at
http://tinyurl.com/2gbgef

Others have also discussed these concepts such as in
rec.radio.amateur.antenna on 1 Jan 2007 entitled "Acceptable
Lightning Ground?" at
http://tinyurl.com/y9bfuz or another at:
http://lightningsafety.com/nlsi_lhm/rtaf3.html or another at:
http://tinyurl.com/2aymw9
The ideal plan is a single point ground with no sneak paths. Sneak paths
are loops that allow lightning current to flow into the equipment room.

Bud will respond as he routinely does complaining that many of these
examples are about radio stations. He says you are not operating a
radio station - only to confuse. Every incoming wire to the building
is a radio antenna to that appliance. That even includes underground
wires. All must connect to that unique ground - single point earth
ground. As was first learned in early 20th Century radio stations, a
surge earthed before it can enter a building means no destructive
paths to earth via radios or household appliances.

We never stop or block surges. As even Franklin demonstrated in
1752, lightning finds earth ground destructively through a wooden
church steeple. By providing a better (more conductive) path to
earth, then repeated lightning strikes cause no damage. But if earth
ground for that Franklin lightning rod is compromised, then a
lightning rod does nothing.

Exact same applies to surge protection. A protector simply makes a
connection to that earth ground. But earth ground - the quality of
and how that connection is made - determines 'system' effectiveness.
Yes - system. Surge protection is a 'system' where the only required
component is a single point earth ground.

Protection is defined by the quality of that connection. A
connection from a wall receptacle to earth is so long, has so many
bends, is bundled with other wires (induces surges on those wires),
etc as to be all but no earth ground. Sharp bends are irrelevant for
60 Hz electricity. Sharp bends significantly reduce wire conductivity
to lightning surges. But again, the surge protector earth ground must
be 'less than 10 feet'. How to make a protector even more effective?
Even less sharp wire bends. Make that earthing wire shorter. A
protector is only as effective as its earth ground.

Demonstrated is why every high reliable facility is fanatic about
its earth system. It must suffer hundreds of direct strikes and never
suffer damage. What determines no damage? How good is that earthing
and connections to earthing? No earth ground means no effective
protection.

Appreciate how badly cable companies were training employees. The
big ones who must also provide reliable phone service are now
fanatical about earthing. For example, two cable guys told me they
recently got training about earthing. As I told them why we do this
and that, the response was, "Is that what they were saying" or "Is
that why we must do that". Virtually every cable company must retrain
their people to understand earthing.

How bad were some? Cable earthed to a water faucet is not effective
earthing. Cable not earthed to same ground as telephone and Ac
electric is bad earthing. One installer even put the ground wire into
a flower box - considered that earthing. As companies now teach
employees about earting, those companies then recommend not using plug-
in protectors.

Whereas cable companies will correct badly earthed installation,
still, earthing remains the responsibliity of a homeowner. Often
cable guys can earth only as good as the earthing system you have
provided. If still earthing AC electric only to cold water pipe,
well, there is nothing the cable company can do about that potential
surge damage. But again, the protection is only as effective as
earthing. Plug-in protectors without earthing may simply earth
surges, destructively, via selective adjacent appliances.

On Aug 13, 1:18 pm, fl_fly_...@xxxxxxxxx wrote:
tom_w
i have been reading about surge protection the last couple of weeks
trying to get a better understanding of it, trying to figure it out.
i'm a bit confused on a few of your points and would appreciate some
clarity.

when you mention earthing, is this exactly the same or is it different
than grounding?

you've said the surge protection does not work if it is not within 10'
of the service panel and earthing system outside, how can this be when
you say the surge protection build into smoke detectors, tv's,
computers ect. is all that is needed to protect it.

this kind of goes with the other questions, if plug in surge
protection does not work because it is not earthed, then how can we
depend on that ground wire at the plug to protect us (our safety) and
the equipment from faults and surges?

i don't want to sound sarcastic, but most cable tv installers in my
area have as much training as the person cutting the grass, and my
cable company sells surge protectors.

.

Relevant Pages

  • Re: Building foundation. Trying to locate ground rod
    ... Therefore a surge is finding earth ground, destructively, via ... However you must remove any electricity ... a wire from cold water pipe to breaker box. ... That bonding wire must be located to 'pick up' water pipe currents ...
    (alt.home.repair)
  • Re: Repairing Lightning Damaged Tvs
    ... > Establish the single point earth ground. ... > be a buried bare 4 AWG ground wire that interconnects AC ... > not connect to any other earthing wire until they all meet at ... > protector must connect from each wire to that bus bar. ...
    (sci.electronics.repair)
  • Re: Driving a seperate ground rod
    ... Your post implies earthing to eliminate surge damage. ... Earthing for transistor protection means earthing also must exceed ... If any one wire is not earthed, ... A protector without that earth ground ...
    (alt.home.repair)
  • Re: Driving a seperate ground rod
    ... Your post implies earthing to eliminate surge damage. ... Earthing for transistor protection means earthing also must exceed ... If any one wire is not earthed, ... A protector without that earth ground ...
    (alt.home.repair)
  • Re: Daisy chining surge protectors
    ... "neutral," the wire commonly called neutral is in fact a ground. ... Is electricity same at both ends of any wire? ... That means protector and adjacent electronics ... Is that a direct earthing connection. ...
    (rec.audio.pro)