Which Power Strip/Surge Protector?
Tracy Rainwater
There are lots of power strip/surge protectors on the market. They range
from $12 at Wal-Mart to over $300. What exactly is needed to protect
electronics from power surges and lightning strikes?
The power in my area seems to be pretty clean. I have never had a problem
with surges or lightning before. I want something to protect me just in
case. My taste in equipment keeps getting more and more expensive. Please
give exact models, why they are good and price if you can. Thanks for any
help you can give.
--
Tracy
Jack Edin
The "Clamping Voltage" is a very important spec for a supressor... Almost
every one you find will have a clamping voltage of 330volts.
What that means is its not a surge, untill 331+ volts...!
So since MY equipment wants 120volts, 330 seems a little over the limit to
ME... You...?
I'm a computer consultant & midnight engineer. I have found a brand called
APC that offers several different series of supressors...
Their best only allows 40volts above nominal through before doing it's job.
This "Let Through Voltage" is best kept low. The lower the better...
They make an 8 outlet model with 3 widely-spaced plugs for those wall-wart
transformer modules...
That is what I use...
There are other factors, like speed. How fast can the supressor react to a
quick surge, etc.
Not to worry, these and other specs are all good on their best models...
Check them out at:
http://www.apcc.com/products/family/index.cfm?id=172
The Net8 is the one I'm using...
http://www.apcc.com/resource/include/techspec_index.cfm?base_sku=NET8&langua
ge=en&LOCAL.APCCountryCode=ww
Hope this helps...
Jack
:)
"Tracy Rainwater" <trai...@bellsouth.net> wrote in message
news:gYxba.18010$lo2....@fe04.atl2.webusenet.com...
B. Earp
> every one you find will have a clamping voltage of 330volts.
>
>
> So since MY equipment wants 120volts, 330 seems a little over the limit to
> ME... You...?
http://www.svconline.com/ar/avinstall_surge_protectionthe_enemy/
> I'm a computer consultant & midnight engineer. I have found a brand called
> APC that offers several different series of supressors...
>
> Their best only allows 40volts above nominal through before doing it's
job.
> This "Let Through Voltage" is best kept low. The lower the better...
To a point - you don't want it to clamp at 122 volts or it'll actually
generate unnecessary spikes since it'll switch on and off too often. This
is exactly what happens when the MOVs wear out, and they wear out with each
hit taken. Anything with electronic chips in it can start to act funny.
> > There are lots of power strip/surge protectors on the market. They
range
> > from $12 at Wal-Mart to over $300. What exactly is needed to protect
> > electronics from power surges and lightning strikes?
Homeowner's insurance if nothing else, or whole house protection at the
service entrance.
w_tom
recommendation is chock full of half truths that promote the
lies of plug-in surge protection. As B Earp so accurately
noted, a low let-through voltage means the surge protector is
degraded in maybe weeks. Surges occur typically once every
eight years.
Joules determines the life expectancy of a surge protector.
Surge protectors are shunt mode devices. They shunt
(distribute, connect) a surge from one wire to all others. A
$5 surge protector is equivalent to a $50 or $100 protector of
same joule rating. Joules determines the life expectancy.
But effectiveness is determined by earth ground. A surge
protector is only as effective as its earth ground.
Every wire entering a building must first connect to central
earth ground, either through a 'whole house' surge protector
(ie telephone, AC electric) or by direct hardwire (ie CATV,
satellite dish). That earthing connection is less than 10
feet. Single point earth ground is THE most important
component of a surge protection 'system'. The telco already
provides a 'whole house' protector on phone lines. Every
surge protector or direct ground wire must connect to same or
central earth ground.
'Whole house' protector mounts in the breaker box to connect
incoming AC electric to that central earth ground ONLY during
a surge. Two minimally acceptable 'whole house' protectors
are sold in Home Depot as Intermatic EG240RC or Siemens
QSA2020. A longer list of other manufacturers are in my 5
Mar 2003 post entitled "Good surge protector?" in the
newsgroup rec.video.satellite.dbs .
All connections to single point ground must be short (less
than 10 foot), direct (not even spliced or sharp bends) until
they all meet at the central ground, and independent (not
shared and not bundled with other wires). More details about
the 'system' are provided in two long discussions in the
newsgroup misc.rural:
Storm and Lightning damage in the country 28 Jul 2002
Lightning Nightmares!! 10 Aug 2002
Principles of surge protection were well established in the
1930s and are why buildings such as telco COs (Central Office
- where the computers are) and cell phone towers can be
directly struck without damage. Principles are based upon
what Franklin demonstrated in 1752. Intercept and earth
lightning before it finds that path to earth via church
steeple or via your transistors.
Ineffective plug-in surge protectors sell on the myth that
if it is a surge protector, then it must be surge protection.
To sell such grossly overpriced, undersized, and mislocated
devices, they must avoid all mention of earth ground. They
must let you wish it stops, blocks, or absorbs lightning.
Nothing stops or blocks lightning - especially not a less than
1 inch component inside that power strip or UPS. To sell
their totally ineffective devices, they must avoid all mention
of earthing. But earthing is the surge protection. An
effective surge protector only connects to the surge
protection - that central earth ground.
I have never seen an effective surge protector sold in
Walmart, Kmart, Staples, CompUSA, Sears, Office Max, or
Lowes. Ineffective surge protectors make themselves obvious.
No dedicated connection to earth ground and they avoid all
discussion about earthing. That missing earth connection
alone demonstrates the quality of every surge protector sold
in the above stores. No earth ground means no effective surge
protection.
As noted above, details (especially about earthing) are in
the newsgroup misc.rural. Further information was posted in
this newsgroup alt.home-theater.misc starting 18 Jan 2003
entitled "Minimum "Joules" for a surge protector." Surge
protector life expectancy is determined by joules. Surge
protector effectiveness is determined by that all so critical
single point earth ground.
Jack Edin's recommendations are woefully erroneous.
Apparently he does not even appreciate the difference between
common mode and differential mode transients. His recommended
products only claim to protect from surges that don't
typically exist. Cite some specs and we can demonstrate the
half truth.
Should you leave having only learned one point - a surge
protector is only as effective as its earth ground.
megabite
the question. I personally have had it 3 seperate occasions, once at work,
fried the pewter and monitor. Twice at home lost the TV, then the HT amp.
Both were repairable. Some so-called "Surge Protectors" are nothing more
than outlet strips that offer little or no protection. Others are so
elaborate that they are able to not only protect from power surges, they
also compensate for voltage drops. Howvever, Lightening Strikes are leaps
and bounds beyond a simple surge.
"Tracy Rainwater" <trai...@bellsouth.net> wrote in message
news:gYxba.18010$lo2....@fe04.atl2.webusenet.com...
J. Harvey
(I'm not stalking you, I'm a regular in this NG as well...)
w_tom doesn't like to mention another (less well known) lightning damage
mechanism that can bypass even his favorite Whole House Protection (which is
not a bad idea BTW).
The entire discussion starts here and goes on for-freaking-ever...
http://groups.google.com/groups?q=%22long+interior+wiring%22
It's a bit of a flamewar... ;-)
The basic point is that long interior wiring can carry induced currents and
result in damaged equipment, even with a 'Whole House Protection' system
(not quite so "whole" as you might think...).
Here's the final outcome after which w_tom went silent:
==================
Here - this is *exactly* what I've been referring to...
www.relcominc.com/download/RelcomSurgeProtection.pdf
Extract from above:
"Simply stated, voltages are transferred from one
metal object to another by capacitance and currents
are transferred from one metal object to another by
mutual inductance. This transfer is not 100%
efficient, but results in substantial voltages and
current nonetheless."
Exactly. Not leaders, not side strikes. Induced currents and resultant
voltages. ...
'Whole House Protection' is not a bad idea, but it does not address the
mechanism described above. One should provide the same sort of concept at
the entrance to equipment that is connected to long wiring - even if such
wiring is inside a (wooden) house.
==================
I will NOT reply to any further postings in this thread. If w_tom posts any
disagreeable replies, then just review the discussion referenced above.
w_tom
the building permits a direct strike to enter the building. A
direct strike is to the building itself or to any incoming
wires. Any surge permitted inside the building will seek
earth ground destructively. Any wires bundled together can
induce a transient from the 'earth grounded' wire to other
wires. Induced because of mutual inductance between adjacent
wires. Mutual inductance means inches apart - not tens or
hundreds of feet.
Because of this mutual inductance, any wire that shunts a
surge to earth must be separate from all other wires. Same
would be true a plug-in surge protector ground. Surge
protectors only connect surges to earth ground. But if the
surge was to be earthed by a protector adjacent to computer,
then the grounding wire is bundled with all other wires.
Mutual inductance induces that surge into other building
wires. Just more paths for a surge to damage transistors
inside the building.
Just another reason why surge protection adjacent to
computers is not effective. If a plug-in surge protector
earths a destructive surge, then the process of earthing that
surge induces that surges throughout the building. That
mutual inductance in bundled wires only causes destructive
surges to appear elsewhere. Better to earth the surge before
it can enter a building - 'whole house' surge protection.
The solution to induced surges is 'whole house' surge
protection AND to enhance that 'oh so critical' central earth
ground. A better central earth ground system means even less
surge inside a building. Plug-in surge protectors provide no
such protection. Plug-in surge protectors have, for all
practical purposes, no earth ground. No earth ground means no
effective surge protection. Just a second reason why plug-in
surge protectors avoid mentioning the most important component
of any surge protection 'system' - the single point earth
ground.
In that previous discussion, J Harvey claimed that
'thousands of volt' surges with the necessary tens or hundreds
of amps are induced in a building by an exterior lightning
bolt. If true (and as others in that discussion noted), then
every radio and TV in the neighborhood would also be damaged.
The power induced by lightning in long wires is so trivial
that it can be earth using only an small NE-2 neon glow bulb.
The NE-2 conducts milliamps to discharge a long wire induced
transient.
EM fields from nearby lightning strikes do not create
interior surges. But a strike that enters the building can be
destructive. Transistors are damaged when part of a circuit
from cloud to earth. Surges damage electronics by finding a
complete electrical path through that appliance to earth
ground. Any transient created by nearby lightning fields is
trivial in comparison. Surge protection is about keeping the
surge outside of a building. Fundamental to all surge
protection is the central earth ground.
J. Harvey
Well maybe just one more...
"w_tom"
> The solution to induced surges is 'whole house' surge
> protection AND to enhance that 'oh so critical' central
> earth ground.
'w_tom' is apparently a sales/marketing 'bot' for a certain company that
just happens <smirk> to sell 'Whole House Protection' equipment. Such
protection systems will help to some extent, but they do *not* provide 100%
coverage against lightning damage (maybe ~60% coverage - which is not bad
BTW - depending on many factors).
'w_tom' will never agree to the existence of any other lightning damage
mechanism except for surges carried into your house by the power and other
cables. He is completely immune to facts, figures, simple logic, first hand
accounts, numbers, references, URLs, detailed explanation, white papers,
etc. He also tends to easily get confused which doesn't help in the
slightest. He is apparently a lost cause since he won't embrace the obvious
truth even after it has been presented to him on a platter.
'w_tom' has been 'outed' (found out) in numerous threads all over various
newsgroups. I'm not the first to tell him that he is wrong in his concepts.
I'm not the first to detect that his education isn't to quite as high a
standard as he might seem to imply. Check Google for some of the history of
his insistence on the incomplete theories of Whole House Protection and
surges. Search on Google for 'w_tom' and 'surge'. Funny stuff. Before
anyone shells out big bucks for a Whole House Protection system, make sure
you do some digging with Google to see who is selling what and why. Me ?
I'm not selling anything.
w_tom
effective as its earth ground. The only thing 'outted' is J
Harvey's nearby lightning strike that will damage household
electronics but not damage exposed radio and TV 'RF'
amplifiers - the transistors hardwired to antennas. Why will
this nearby strike damage appliances but not damage sensitive
radio receivers? J Harvey promotes a myth which he only
proves by a personal event and speculation.
As for "big bucks for a Whole House Protection system",
well, that also demonstrates his integrity. A minimally
effective 'whole house' surge protector for residential AC
electric is not expensive. Sold in Home Depot - Intermatic
EG240RC or Siemens QSA2020. Other more expensive solutions
exist. They cost on the order of 10 to 50 times less per
protected appliance compared to plug-in surge protectors.
'Whole house' protectors only do better what I had been doing
with custom designs a decade earlier and with stunning success
(and one still unexplained failure).
I am not insulting others to appear credible. The reader is
provided valuable information from an engineer that has
probably been building surge protectors before J Harvey even
existed. Surge protection is about earthing a surge before it
can enter the building.
J. Harvey
> Bottom line remains <in spite of my cover being blown> -
(The above introduction means that my guess about his motives were correct.
He really is a sales/marketing bot.)
> Why will this nearby strike damage appliances
> but not damage sensitive radio receivers?
It was *long* wires. (I've told him so many times but he still doesn't get
it. Sigh... Hopeless...)
> ...promotes a myth which he only
> proves by a personal event and speculation.
B.S.!! I previously provided a URL that worked last time to shut you up.
Here, let's try it again...
http://www.relcominc.com/download/RelcomSurgeProtection.pdf
Why don't you simply admit that the mechanism described on the above webpage
(and thousands more references) actually exists along side the mechanism
that you feel so strongly about (power line surges) ? Just stop denying it.
It's *really* annoying.
> A minimally effective 'whole house' surge protector
> for residential AC electric is not expensive.
"Minimally effective" ? How much is one that actually does something ? Is
the effective versions more than $100 ? Maybe $200 ? Maybe $300 ? Maybe
some would call that 'big bucks' - especially if it only solves perhaps ~60%
of the lightning problem. Maybe it would be better to purchase a useless
plug-in surge protector that actually comes with $25k equipment insurance ?
(not really).
> I am not insulting others to appear credible.
You sure comes across that way sometimes....you certainly started off on the
wrong foot with me just before I called you an "arrogent prick". Remember ?
> The reader is provided valuable information
> from an engineer that has probably been
> building surge protectors before J Harvey
> even existed.
Advancing age would explain some of your less attractive attributes.
BTW - for those that award points for formal education...
J. Harvey,
BSc Physics.
w_tom
performance. Here's proof from Monster Cable:
http://www.monstercable.com/company_info/
Damage to human liver due to medication, fatty foods, or
liver-related illnesses such as hepatitis, cirrhosis, or
specific cholesterol-lowering agents, immuno-suppresant drugs,
etc can be solved a nutritional supplement. Here's proof from
Liver-rite:
http://www.longevita.com/Detail.asp?ProductID=90
And nearby lighting strikes will damage household
electronics. Here's proof from a cable manufacturer:
http://www.relcominc.com/download/RelcomSurgeProtection.pdf
How to promote a myth: cite non-technical sales claims from
companies who first invent a mythical problem - then sell a
solution.
Relcom's cable cannot even provide effective surge
protection. So instead they invent 'surge from a nearby
lighting strike' to justify their product? What kind of
technical proof it that? Unfortunately that junk science is
considered technical (numerical) fact to J Harvey who claims
that a nearby lightning strike will create surge damage.
J Harvey claimed much technical education especially in
radio frequency technology. However he cannot even provide
basic numbers from electromagnetic wave theory to justify his
claim. How does he explain that tens or hundreds of amp
surges in household power wires when the same field could not
even damage sensitive RF transistors in every nearby radio and
TV? And what was this DC surge he cited in a previous
thread? J Harvey is convinced of these mythical 'nearby
lightning surges' only because Relcom says they exist? Relcom
conveniently has a product to 'cure' the mythical problem.
Transients induced on a long wire are so insignificant as to
be shunted even by an NE-2 neon lamp. The mythical surge is
really nothing more than noise. In the meantime, a Relcom
product is so poor that it cannot even provide protection from
potentially destructive surges. Relcom is the citation from
one who never learned basic EM Wave theory. Not even one
number is provided to demonstrate this mythical surge.
J Harvey's only proof is based upon an urban myth promoted
to sell a product. And so he again insults me - so that
others will not notice: J Harvey provides no technical proof
that he even has the education he previously claimed.
J. Harvey
Induced Surges and Long Wires - the Flame War continues...
Background:
'w_tom' seems to hold the position that *all* lightning damage can be
prevented with the installation of a 'Whole House Protection' system at the
electrical service entrance. I simply reported that near-by strikes can
cause massive ground current surges that can couple induced currents into
nearby long wiring (even inside a nearby wooden house) and these induced
currents can produce voltages that might damage some sensitive electronics
(not all electronics, just the devices and inputs that are sensitive).
'w_tom' is consistent in his denials even while admitting facts that support
my point.
'w_tom' complains about insults even while he calls into question other's
education. He claims that anyone that tries to correct him must be
uneducated. He himself has repeatedly alluded to being a trained engineer,
but he has never come clean about his formal education (I have already - BSc
Physics). I really don't care, I prefer to argue with simple facts and
transparent logic. He is extremely arrogant and rude, but then he cries
'Boo Hoo Hoo' when his errors are highlighted and his insults returned.
'w_tom' is obviously a sales / marketing bot for a company that sells 'Whole
House Protection' systems. I'm not selling anything. He showed up on the
Dell newsgroup and now he's here on this one. The arguments are exactly the
same.
My only point is that such 'Whole House Protection' systems might provide
about ~60% coverage, certainly not 100% as 'w_tom' would like to have you
believe.
"w_tom" wrote for a second time:
> Transients induced on a long wire are so insignificant
> as to be shunted even by an NE-2 neon lamp. The
> mythical surge is really nothing more than noise.
'w_tom' - this is getting really boring because I've explained all this
before but you still don't get it. It is all so very, very simple; please
try to understand the following. Please take a 'smart pill' before you
respond again.
1) A NE-2 neon bulb will fire at about 70 volts.
2) The 'mythical' induced surge that you claim is 'nothing more than
noise' - well, you've just admitted that the 'noise' can be more than 70
volts with your proposal to use a NE-2 neon bulb to provide some protection.
This is the second time that you've admitted that fact - thank you for
making my point (it's too bad that you refuse, or are simply too stoopid, to
acknowledge it).
(NOTE: 'w_tom' has just admitted that which he will continue to deny.)
3) You're right, these little surges induced into the nearby long wires are
not the same magnitude as the nearby ~100,000 amp strike, but 70 volts is
still too much for some sensitive inputs. Not all inputs are properly
bypassed with internal protective devices (many are, some aren't). Some
inputs are connected directly to sensitive IC (Integrated Circuit) input
pins. Those sorts of inputs can easily be fried by 70 volts. I'm not
referring to laundry equipment.
4) Unfortunately, most long wires *aren't* shunted by a NE-2 neon lamp. The
induced surge would be limited to 70 volts with the NE-2 neon bulb. Without
the NE-2 neon bulb to provide protection, then it could be several hundreds
of volts. If the surge was only about 70 volts, then it is hardly worth the
effort to fit NE-2 neon bulbs. Therefore, you've admitted that the induced
surges are sometimes about several hundred volts.
5) The conclusion are obvious:
a) Such induced surges (up to about a few hundred volts) do exist.
b) 'w_tom' has admitted as much by his mention of neon bulbs.
c) 'w_tom' will (again) fail to see that he has admitted it.
d) 'w_tom' is too stoopid to see these obvious conclusions.
Unlike you, I'm not a self-proclaimed expert in protecting *laundry
equipment*. I'm discussing modern electronics where even a 70 volt surge on
the wrong input will destroy the IC. In the absence of customer installed
NE-2 neon bulbs, those induced surges can be much more than 70 volts. Many
equipment will have some very good built-in protection, some will not.
> Relcom is the citation from one who never learned
> basic EM Wave theory. Not even one number is
> provided to demonstrate this mythical surge.
1) We've had this discussion. I've already mentioned my education,
experience, background, and more. You are still the elusive and mysterious
'w_tom' that apparently slept through Grade 3 science and failed EE101. You
have never mentioned any of your education other than you've read a few of
the Polyphaser WebPages (see some references below...).
2) I'm not the only to detect that your education is weaker than it might
seem. You have a way of wording things that makes it sound like you're an
expert., but a closer examination starts to reveal the subtle errors.
3) Numbers provided above (again). You have already admitted to the
existence of these 'mythical' surges. (Please refer to the conclusions
under bullet 5) above.)
> J Harvey's only proof is based upon an urban myth
> promoted to sell a product.
I'm not selling anything !! Check Google - I've got many interests. But
'w_tom' is a obviously marketing / sales bot for some unknown company
selling 'Whole House Protection' systems.
> And so he again insults me - so that others will
> not notice: J Harvey provides no technical proof
> that he even has the education he previously claimed.
1) I insult you because, apparently, you really are stoopid. (And you
started it !)
2) How the hell does one prove education via a newsgroup posting ? I
suppose that you could confirm that I'm a regular on 'alt.auto.mercedes' and
that perhaps indicates that I'm not a high-school drop-out. Do I need to
scan in my BSc Physics degree ?
Look at what Google has found about 'w_tom':
w_t...@hotmail.com
"A benchmark in surge protection is Polyphaser...
Polyphaser's application notes are considered
legendary by industry professionals."
W_tom
"This is well documented where real surge protector
manufacturers reside. Polyphaser application notes
are considered legendary."
w_t...@usa.net
"Serious surge protector manufacturers...polyphaser"
'w_tom' is obviously a marketing / sales bot for a company that just happens
to sell Whole House Protection systems. Such systems do provide some
benefits (I never said they didn't), but they do *not* provide 100%
protection except perhaps in metal buildings.
'w_tom' - consider yourself exposed in this second newsgroup.
('w_tom' will repond again - but his next response won't be any better than
the previous ones and he will fail to grasp the obvious logic as laid out
above. Hopefully the regulars on this newsgroup won't be seduced by his
salesmanship now that the subtle errors have been highlighted. You can
still buy a Whole House Portection system if you want to, but just don't
think that you're immune to lightning induced damage with such a system -
unless your house is made of metal.)
w_tom
that it can only provide 70 volts at milliamps of current.
That is not a surge. Surges on AC electric wires are 300+
volts with tens or hundreds of amps.
You have a physics background. Apparently it does not
include real world, practical experience. I was building
surge protectors before the PC existed and maybe even before
you existed. As an engineer, I also demanded reasons why and
got those answers from the many experiments, my EE education,
books, datasheets, and technical papers. Had many interesting
failures and successes. Only direct strikes to building or
incoming wires created those voltages and currents necessary
to cause damage. Induces surges are created when a lightning
strike does conduct inside the building. Anything induced
onto long wires by a nearby strike causes a transient well
below what every appliance must withstand without damage, as
even defined by numbers from the Computer Business Equipment
Manufacturer's Association.
But again, where are your numbers that prove a destructive
surge? Where are the EM field numbers that in turn create how
many volts and current on the 100 foot wire? The only number
provided is from me - the NE-2 neon glow lamp. 70 volts
through a milliamp device is not a surge - which explains why
the nearby strike cannot even damage radios.
There are IEEE papers on field effects due to nearby
strikes. They discuss noise that would interfere with data
transmission - not surges. Techniques minimize data loss due
to nearby strike interference. But the nearby lightning
strike does not create surges. 70 volts when under a
milliamp load is not a surge.
J. Harvey
> Induced surge from a nearby lightning strike is so trivial
> that it can only provide 70 volts at milliamps of current.
> That is not a surge. Surges on AC electric wires are
> 300+ volts with tens or hundreds of amps.
1) IC inputs can be damaged by even the static from a human ESD event.
2) If you have 70+ volts (which you have already admitted), then the maximum
available peak current is set by the characteristic impedance of the long
wire in common mode.
3) The characteristic impedance might be something like 100 ohms or so, but
it depends on many factors. It won't be even 1 kohm. Do you understand
about 'characteristic impedance' ?
4) The peak available current would be just 'milliamps', yes. You're right.
Maybe about SEVEN HUNDRED milliamps (~700 mA), roughly (nearly one amp).
5) Far more than required to 'blow' an otherwise unprotected IC input.
6) If you haven't installed a NE-2 bulb, then the voltage would not be
limited to 70 volts.
7) If you haven't installed a NE-2 neon bulb, then the peak current might
easily exceed 1 amp.
8) Most equipment doesn't come with NE-2 neon bulbs on all the sensitive
inputs, and most people reading this newsgroup will admit that they haven't
installed any neon bulbs recently.
9) You obviously have more experience protecting laundry equipment than you
do dealing with modern electronic equipment.
> You have a physics background.
We're making some progress... ...thank you.
> Apparently it does not include real world,
> practical experience.
I've already reported my own first-hand accounts that are perfectly
explained by the induced current mechanism and are not explainable with the
mechanisms that you will admit. I've already provided one reference and
there are plenty more available. Try Google and 'lightning' 'induced'
search terms.
> I was building surge protectors before the PC existed
> and maybe even before you existed.
So what ? Your advancing age only helps to prove that you can't teach an
old dog new tricks. You're apparently immune to further education. I'm not
that young that I don't know about these sorts of things. I've had a Ham
Radio license for more than 25 years, so you can work out my approximate age
if you assume how old I was when I passed the exam.
> As an engineer...my EE education...
We're making some progress...
> Anything induced onto long wires by a nearby strike
> causes a transient...
Thank you - we're making some serious progress here...
NOTE - 'w_tom' has finally been forced to admit the obvious.
> ... well below what every appliance...
(appliance = laundry equipment ?)
> ...must withstand without damage, as even defined by
> numbers from the Computer Business Equipment
> Manufacturer's Association.
***There is your error !!!! ***
There are many electronic devices that do not meet those standards.
Shortwave radios (not applicable)
Ham Radios (not applicable)
Alarm panels (ignored)
Telephone answering machines (probably ignored)
Cheap imported telephones (ignored)
Even some PC accessories (ignored for cost reasons)
Etc.
Etc.
Etc.
It is a really bad assumption to make; that all equipment meets those
standards. That is such a trivially-obvious error that I'm surprised that
you've made it.
Why do you think that they created those standards ? To try to start
solving the problem. And now you've been denying that the problem ever
existed ?
Not very bright...
> But again, where are your numbers that prove a destructive
> surge? Where are the EM field numbers that in turn create how
> many volts and current on the 100 foot wire? The only number
> provided is from me - the NE-2 neon glow lamp. 70 volts...
...and that one number is more than sufficient to blow your denials out of
the water.
Your reference to the standard is even more evidence that you've been
blowing smoke.
> through a milliamp device is not a surge - which explains why
> the nearby strike cannot even damage radios.
But it can damage Shortwave and Ham radios connected to long wires. If you
think that I'm referring to portable radios with built-in antennas, then
that means that you're not paying attention and you still don't get it.
That is your failing - not mine - I've explained it to you several time.
> 70 volts when under a <~700+>
> milliamp load is not a surge.
Tell that to a CMOS IC that has one fried input pin.
Look up ESD and the sorts of handling procedure put into place for ICs,
devices, circuit cards, and even assembled devices.
'w_tom' - look - the post that you just made has accomplished nothing except
to prove that you're immune to logic. I have identified your bad
assumption.
You're simply wrong and you aren't quite the lightning damage expert that
you think.
Sorry - but that is simply the truth.
B. Earp
> lightning surges' only because Relcom says they exist?
The power generation/distribution company on the Canadian side of Niagara
Falls says they exist:
"Three elements are needed to produce a problematic power line
disturbance: a source, a coupling channel and a receptor.
"The following are primary coupling methods:
- Conductive coupling - disturbance is conducted through the power lines
into the equipment.
- Coupling through common impedance - occurs when currents from two
different circuits flow through a common impedance such as a common ground.
The voltage drop across the impedance for each circuit is influenced by the
other.
- Radiated electromagnetic fields - occurs unintentionally due to arc
welders, lightning and intermittent switching of contacts or by intentional
radiation such as that from broadcast stations and radar transmitters."
...and...
" - EMI/RFI can also be either conductively coupled, or capacitively or
inductively coupled."
That and more in "Power Quality Reference Guide" (1 Meg):
http://www.energyefficiency.org/eecentre/eecentre.nsf/9a330973e9d58922852569
c600572690/5f494e72fae56933852569e40079078d/$FILE/POWERQ.PDF
Chapter 10 is entitled "Mitigation Techniques". The handy fold-out tables
throughout the guide aren't in the pdf, but the price of the nicely put
together print version is low (if still available). The site is run by a
non-profit organization, and the electric company was government-run when
the book was written. Read: neutral standpoint with regard to protection
gizmos.
For what it's worth, I've seen what lightning hitting the back yard can do,
and that is to turn all appliances under the roof into toast. To give an
idea of the severity, the preamp was full of exploded ICs such as ordinary
quad gates, and many traces had vaporized.
Insurance wrote everything off.
w_tom
with its so sensitive transistor not damaged? J Harvey would
have you believe that CMOS semiconductors, damaged by 7 or 30
volts, are easily damaged by a 70 volt, milliamp transient to
a system. Reality. Once those ICs become part of a bigger
design - the system, then those ICs are not damaged by trivial
transients. J Harvey made this same argument in another
newsgroup. He was instructed to learn about a European
requirement for all CMOS inputs to even withstand thousands of
voltage without damage. How do these CMOS devices withstand
thousands of volts? Easy once they become part of the system
and once one first learns from manufacturer data sheets.
That is the point. J Harvey does not have experience - or is
simply putting up 'straw man' arguments to confuse the
reader. Either way, surges created by nearby strikes are
mythical. Surges are direct strike to building or incoming
wires. Don't let him confuse you with characteristic
impedance. Its not relevant. The NE-2 is connected directly
to the long wire - no characteristic impedance involved. He
would even have you believe that an antenna is 100% efficient
- will absorb all energy in EM fields. But one need only
attach an NE-2 neon glow lamp to a 100' long wire. No
surges. No destructive energy. Just some induced noise - a
few milliamps at only 70 volts.
Which returns to the original post. That power strip surge
protector is doing nothing productive for the customer. It is
so grossly overpriced that manufacturers would rather not
mention anything about earthing - the most critical component
of any effective surge protection system. If they discussed
earthing, then you would not buy their extravagantly
profitable product.
Earthing is what a 'whole house' surge protector connects
to. Earthing - a distance less than 10 feet - is why all
incoming utilities enter at the same service entrance. Surge
protection is about earthing a surge. Plug-in surge
protectors cannot do that. Plug-in surge protectors sell at
such gross profits as to avoid all discussion earth ground.
Earthing a surge (or trivial transients from nearby strikes)
is what surge protection is all about. A surge protector is
only as effective as its earth ground.
> ...
J. Harvey
> But one need only attach an NE-2 neon glow lamp
> to a 100' long wire. No surges. No destructive energy.
> Just some induced noise - a few milliamps at only 70 volts.
Okay - how many people reading this post have installed NE-2 neon bulbs into
the sensitive circuits that are connected to the long wires running around
their wooden house ? Alarm wiring, shortwave antennas, PC network wiring,
low voltage signalling, home theatre '2nd Room' outputs, etc.
How many ? Show of hands ? Any ? BWAHAHAHA !!!!
(BTW - It is a good idea because it would provide *some* help for *some*
sensitive inputs connected to long wiring in your wodden house. That is
in-line with what I have been saying all along. Not really practical for
most people !)
Shielded wiring, if done correctly, is also a good idea. Don't use cheap
"dimestore" (low percentage shield coverage percentage) shielded wiring when
running long audio lines from your main home theatre '2nd Room' outputs all
the way to your bedroom system. Use *very good* wiring with *good*
shielding. Or put the audio lines into a grounded metal conduit.
PLEASE NOTE:
'w_tom' is a self-proclaimed lightning expert, but with a huge,
unrepairable, blindspot. He is *not* the expert that he wants you to
believe. Take his advice and filter it carefully before buying one of his
Whole House Protection systems. He is selling watered-down snake oil.
Might help a bit, but it is not the complete solution. It can't be. Simple
logic. Unless you live in a metal house.
I've already made my point one hundred times and he is too stoopid to admit
it. I don't care about 'w_tom', he is a lost cause. Most of the lurkers
will understand what I am referring to and will have gotten the message by
now. 'w_tom' will never get it because he is too stoopid.
This is getting boring - I might not reply to 'w_tom's next stoopid post.
'w_tom' - PLEASE - for the sake of all humanity....please...
GET A BRAIN AND HAVE IT INSTALLED.
w_tom
category) with surges (one example from the category).
Surges are only one type of problematic power disturbance.
The man in FL had a direct strike to tree behind his house.
Analysis. It was a direct strike. Surge seeking earth
ground. From tree into buried telephone wire. Enters
building passing through household appliance, destructively,
to obtain earth ground on other side of building. Complete
circuit defined because building did not have the all so
essential single point earth ground system. A direct strike
that some would 'assume' to be field induced because they did
not understand the circuit. In this case, the building did
not use the single point earth ground and suffered repeated
household appliance failure. Household appliances became part
of a destructive circuit from cloud to earth ground.
A similar experience among campers. Those sleeping
perpendicular to the struck tree were not hurt. Those
sleeping pointed towards the tree suffered a direct strike and
burns. Lightning struck the tree seeking earth ground (which
means charges elsewhere in the earth). Down tree into earth,
then up into sleeping human body feet, and back down into
earth via head. Again a direct strike circuit from cloud to
earth in which, if I remember, two boys had to be airlifted to
hospital.
Were only those two boys hurt by nearby EM fields? No. A
direct strike did the damage. But again, the naive did not
understand a direct strike circuit and instead blamed nearby
EM fields for hurting only two campers.
Demonstrated is a another problem with those who promote EM
fields as surges. They don't first learn the destructive
circuit. They assume it must have been an EM field because
they did not understand how lightning works. They did not
learn the circuit.
Lightning can create noise problems that interfere even with
power company control equipment. It is noise - not surges.
To have the power of surges, a direct strike is required.
To claim that an EM field from a nearby strike causes a
surge, then one must demonstrate using electromagnetic wave
theory equations. Where are the numbers? Where are Maxwell's
equations? Those numbers and calculations are not being
provided because those making EM claims don't even possess
sufficient EM field theory.
Reality is that nearby lightning strikes do not create
destructive EM fields. They create noise. EMI/RFI is noise -
a problematic power disturbance - but not a surge. EMI/RFI
does not damage electronic appliances.
That Canadian power company is not talking only about
surges. They are discussing problematic power disturbance.
Big difference. EM fields from nearby lightning strikes do
not create surges.
But then any EM induced transient sufficient to damage a
household appliance also would be made redundant by a 'whole
house' surge protector - again making all this nonsense about
EM induced surges irrelevant.
w_tom
dispute technical facts, then J Harvey insults. EM fields
from nearby lightning strikes do not create surges. Such
fields can create noise that interferes with data transmission
- but does not damage hardware.
IEEE papers discuss induced surges by specifically showing
in that figure the lightning bolt striking the building. An
electrical conductor carrying the direct surge induces or
couples a surge onto other, adjacent wires. Induced surge.
EM fields between wires - not some distant lightning strike.
Surge protection is about earthing a surge before it can
enter the building. Every incoming utility must connect to
central earth ground, either by hardwire or via a surge
protector, before entering the building. Surge protection is
about earthing a surge. That 'whole house' surge protector
is as effective as its earth ground.
B. Earp
news:3E74BFED...@hotmail.com...
yikers...where's discussion of the man in FL and two campers coming from?
Let me start again: The average HT owner already has insurance, and I'm
suggesting there's no reason to spend more on additional protection unless
inconvenience can be effectively prevented within reasonable cost. I never
blamed EMI for the blowing up - as in actual shrapnel - of logic chips,
which, by the way, are not connected directly to an I/O interface, nor, for
that matter, long wires (was a stereo, not HT). I did say EMI is a well
known cause of transients, before moving on to 'chapter 10, mitigation
techniques'.
Now, if someone asked, "Can capacitively or inductively coupled transients
stemming from lightning be strong enough to damage delicate yet unbuffered
devices connected directly to a long wire?" and the only two responses you
could choose from were quick and simple "possible" and "impossible" then
which would it be?
For the record, I do not work for an insurance company.
J. Harvey
Hey 'w_tom' - read it and weap...
http://www.ewh.ieee.org/soc/pes/lpdl/archive/rachidi.pdf
"A cloud-to-ground lightning flash generates a transient electromagnetic
field which can induce overvoltages of significant magnitudes on overhead
power lines situated in the vicinity."
Although this paper is discussing power lines, logically, that same
'transient electromagnetic field' can generate significant voltages and
currents in nearby (he says ~200m) low voltage signal wiring. There is
nothing special about power lines. They're all acting as antennas in the
common mode.
You are being stoopid to keep denying it.
It also shows that you don't have a good feel for the EM effects of having
100,000 amps running down a tree in your backyard and the coupling to long
wires in the vicinity. Don't forget the ground current surge in your
analysis.
YOU have a lot of learning to do...
Why don't you start with Google:
http://www.google.com/search?q=analysis+lightning+field+induced
J. Harvey
> As usual, when J Harvey cannot provide numbers
> and cannot dispute technical facts, then J Harvey insults.
I've been providing technical facts to you for a week or so. I've provided
references and you've ignored them. You're stoopid. You're not a lightning
expert. You're a fake. You're a badly programmed marketing and sales bot
for some company that is selling something called a Whole House Protection
system.
> EM fields from nearby lightning strikes do not create surges.
> Such fields can create noise that interferes with data transmission
> - but does not damage hardware.
What a stoopid statement.
If it takes 1 volt of noise to cause a data transmission error, how the heck
can you think that you won't occasionally have a 10 volt or 100 volt surge
that WOULD cause damage to an unprotected single chip microcontroller in
some electronic gadget that is connected to long wires.
How do you make it so consistent in such a narrow range ?
Moron.
J. Harvey
> http://www.ewh.ieee.org/soc/pes/lpdl/archive/rachidi.pdf
>
> "A cloud-to-ground lightning flash generates a transient electromagnetic
> field which can induce overvoltages of significant magnitudes on overhead
> power lines situated in the vicinity."
>
> Although this paper is discussing power lines, logically, that same
> 'transient electromagnetic field' can generate significant voltages and
> currents in nearby (he says ~200m) low voltage signal wiring. There is
> nothing special about power lines. They're all acting as antennas in the
> common mode.
BTW - note that the above reference is IEEE before you start picking at it.
Moron.
And your mama was ugly too.
If more people knew about these sorts of things, then you would have already
been 'bitch slapped' off the newsgroups a long time ago. You just wander
around the newsgroups spreading your lies and trying to sell your Whole
House Protection systems.
Good luck.
Sales down this month ?
w_tom
system, then yes, lightning induced transients on long wires
could damage some CMOS integrated circuits - just as static
electricity can damage individual components not part of an
appliance. However the discussion is about an appliance - ICs
in appliances, entire building responses in regard to nearby
strikes, and even strange circuits that conduct a direct
strike, destructively, into a household of electronic
appliances. Damage to ICs inside an appliance is so
unnecessary as to be considered human failure. And lightning
induced EM fields just don't create such damage.
Insurance is another level of protection. Yes even humans
can make mistakes. Unlike the 'so called' warranty provided
by plug-in surge protectors, an insurance broker must report
up front conditions of his coverage and honor that policy per
Federal laws. Insurance is a secondary level of protection
if, for example, the 'whole house' protection system has been
compromised.
But 'whole house' surge protection is so inexpensive and so
effective. Typically about $1 per protected appliance.
Compare that to maybe $50 for ineffective (plug-in) protection
for only 1 appliance. 'Whole house' protection is so
effective and so inexpensive that it is installed free by the
telco on phone lines. CATV and satellite dish wires are
suppose to be installed with protection - the dedicated
hardwired connection to central earth ground. Neither CATV
nor satellite dish cables require a separate surge protector
because they can be and must be hardwired to central earth
ground.
Surge protectors don't provide surge protection. Protection
comes from central earth ground. Surge protectors or direct
hardwires 'surge protect' an incoming utility by making a
connection to earth ground during the surge.
Again, this is so inexpensive that a homeowner would be
foolish not to have installed such protection. Some parts of
that surge protection 'system' are also required by NEC for
human safety. Homeowner's insurance that specifically states
coverage for surge damage is a good added level of
protection. But better to first avoid the damage rather than
only protect after the fact - especially when effective surge
protection costs less than ineffective plug-in surge
protectors.
J. Harvey
> If limiting a discussion to ICs not connected as part of a
> system, then yes, lightning induced transients on long wires
> could damage some CMOS integrated circuits
I was referring to ICs at the *edge* (input) of the "appliance" where the
"appliance" is connected to a long wire and the "appliance" doesn't have
sufficiant protection circuitry. This is exactly what I was referring to.
> Damage to ICs inside an appliance is so
> unnecessary as to be considered human failure.
I wasn't referring to ICs deep down inside the "appliance". I was referring
to ICs that are directly conencted to the outside world (long wires).
> And lightning induced EM fields just don't create
> such damage.
But it will trigger a customer-installed NE-2 neon bulb at 70 volts ?
Dumb.
Using the word "appliance" in a home theatre newsgroup. The man is an
expert in protecting your "appliances".