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cable modem not working with router

 
 
Dan C
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      10-27-2007
On Sat, 27 Oct 2007 03:11:04 -0500, Plato wrote:

>> Everything was working fine for over a year, had a lightning storm and
>> after that the internet wouldn't connect. Here's what is interesting:


> Too bad you didn't have any surge protectors in line. Get some to avoid
> future problems.


A surge protector will do nothing at all to protect against a close
lightning hit. Nothing.


--
"Ubuntu" -- an African word, meaning "Slackware is too hard for me".

 
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Plato
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      10-29-2007
Dan C wrote:
>
> On Sat, 27 Oct 2007 03:11:04 -0500, Plato wrote:
>
> >> Everything was working fine for over a year, had a lightning storm and
> >> after that the internet wouldn't connect. Here's what is interesting:

>
> > Too bad you didn't have any surge protectors in line. Get some to avoid
> > future problems.

>
> A surge protector will do nothing at all to protect against a close
> lightning hit. Nothing.



Agreed.













--
http://www.bootdisk.com/


 
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kráftéé
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      10-29-2007
Plato wrote:
> Dan C wrote:
>>
>> On Sat, 27 Oct 2007 03:11:04 -0500, Plato wrote:
>>
>>>> Everything was working fine for over a year, had a lightning
>>>> storm and after that the internet wouldn't connect. Here's what
>>>> is interesting:

>>
>>> Too bad you didn't have any surge protectors in line. Get some to
>>> avoid future problems.

>>
>> A surge protector will do nothing at all to protect against a close
>> lightning hit. Nothing.

>
>
> Agreed.


But, & it is a biggy it may have helped with a transient voltage spike
caused by a lightning strike.

Lightning goes it own way to the earth, so any protection is better
than non at all...


 
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Jim McCardle
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      10-29-2007
Several Years ago my sister had a similar problem. She lives on a
farm and is about 4km from the exchange. She had a dialup modem
service. After a bad storm her internet died but the computer still
worked and so did the landline phone. She asked me to look at it for
her and the internal PCI modem had holes in the top of several
Integrated circuits on the modem card. I have seen this sort of thing
before but I was truly surprised that it had not wrecked the computer.
I replaced the internal modem with an external one and installed the
software for it and she was then a happy vegemite.

She now has ADSL but it is an external modem and I have not yet seen a
damaged ADSL modem but I suppose the energy in a lightning strike is
probably enough to wreck one. We had a lightning at the place I
worked at and it destroyed in excess of $250k worth of terminals and
computers. We had a central computer building feeding many others by
RS232 land lines in those days (about 10 years ago now).

Basically what happens is that if the lightning strike was at her
place it could momentarily move 10 or 20kv above or below the
potential at the telephone exchange, the energy behind a lightning
bolt is very high and will blow the **** out of any weak link. If the
hit is at the exchange end then the phone line at the house will try
and become elevated by the 10 or 20kv.
Not many lightning suppressors will clamp that.

Jim McCardle
================================================== ==

On Mon, 29 Oct 2007 11:23:26 -0000, "kráftéé"
<kraftee@b&e-cottee.me.uk> wrote:

>Plato wrote:
>> Dan C wrote:
>>>
>>> On Sat, 27 Oct 2007 03:11:04 -0500, Plato wrote:
>>>
>>>>> Everything was working fine for over a year, had a lightning
>>>>> storm and after that the internet wouldn't connect. Here's what
>>>>> is interesting:
>>>
>>>> Too bad you didn't have any surge protectors in line. Get some to
>>>> avoid future problems.
>>>
>>> A surge protector will do nothing at all to protect against a close
>>> lightning hit. Nothing.

>>
>>
>> Agreed.

>
>But, & it is a biggy it may have helped with a transient voltage spike
>caused by a lightning strike.
>
>Lightning goes it own way to the earth, so any protection is better
>than non at all...
>

 
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kráftéé
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Posts: n/a
 
      10-29-2007
Jim McCardle wrote:
> Several Years ago my sister had a similar problem. She lives on a
> farm and is about 4km from the exchange. She had a dialup modem
> service. After a bad storm her internet died but the computer still
> worked and so did the landline phone. She asked me to look at it
> for her and the internal PCI modem had holes in the top of several
> Integrated circuits on the modem card. I have seen this sort of
> thing before but I was truly surprised that it had not wrecked the
> computer. I replaced the internal modem with an external one and
> installed the software for it and she was then a happy vegemite.
>
> She now has ADSL but it is an external modem and I have not yet
> seen a damaged ADSL modem but I suppose the energy in a lightning
> strike is probably enough to wreck one. We had a lightning at the
> place I worked at and it destroyed in excess of $250k worth of
> terminals and computers. We had a central computer building
> feeding many others by RS232 land lines in those days (about 10
> years ago now).
>
> Basically what happens is that if the lightning strike was at her
> place it could momentarily move 10 or 20kv above or below the
> potential at the telephone exchange, the energy behind a lightning
> bolt is very high and will blow the **** out of any weak link. If
> the hit is at the exchange end then the phone line at the house
> will try and become elevated by the 10 or 20kv.
> Not many lightning suppressors will clamp that.
>

True but as was proved in a local lightning strike it will make it's
way to the lowest resistance to (or should that be from) earth.

This strike hit a 20Pr aeriel cable flashed one way into a school,
There were reports of blue flashes going down corridors as it followed
the internal cabling but it didn't blow any equipment as such but it
did blow individual ports on their switches. The school had the
normal mixture of anti surge devices

Other users fed from the pole were a mixed bag of phones broken,
socket working, phones working but socket blown & even a couple with
no telephone problems but with blown televisions.

I'm not advocating the use of any anti surge as a complete defence but
what I'm saying is that any protection is better than nothing at all,
just by making it a little more difficult to get thru could be enough
for the transient to go elsewhere & your equipment could be saved


 
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Buffalo
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      10-29-2007
kráftéé wrote:
> True but as was proved in a local lightning strike it will make it's
> way to the lowest resistance to (or should that be from) earth.
>
> This strike hit a 20Pr aeriel cable flashed one way into a school,
> There were reports of blue flashes going down corridors as it followed
> the internal cabling but it didn't blow any equipment as such but it
> did blow individual ports on their switches. The school had the
> normal mixture of anti surge devices
>
> Other users fed from the pole were a mixed bag of phones broken,
> socket working, phones working but socket blown & even a couple with
> no telephone problems but with blown televisions.
>
> I'm not advocating the use of any anti surge as a complete defence but
> what I'm saying is that any protection is better than nothing at all,
> just by making it a little more difficult to get thru could be enough
> for the transient to go elsewhere & your equipment could be saved


Sounds good to me.
A friend of mine must have had a close strike.
His PC had a surge protector and didn't get hurt this time, but he lost his
answering machine, his "wireless" indoor outdoor thermometer (how, beats me
except that it circuitry is probably very weak and it even knocked the
outside sending unit off a wooden post,), his Sony TV (which was off) no
longer worked, his water pump relay mounted on the power pole was fried,
lost a rotator on one of his ham radio antennas, fried a ham radio amplifier
and he lost one electrical outlet in his unattached garage (nothing was
plugged into it).
None of the other damaged units had a surge protector.

The outlet in the garage amazed me. It was the only one on that circuit and
it was the outside one located within 4' from the electrical panel. It
caused a direct short (that would also trip the main breaker feeding the
garage), so we disconnected it at the panel and that solved that. He didn't
want me to pull a new wire to it because he said he never used it anyways.
It was wired in romex and I would be very interested to see where it shorted
out (staple, connector,?). No apparent burns,smells, etc at the panel or at
the outlet itself (yes, I remove the receptacle and looked ; and even with
the wires off the receptacle and the breaker, the wire was still shorted).

He has since had the power company install (at his expense) two hefty surge
protection units (meter based units from MeterTreater) at the power pole
and hopefully that will help a lot.
He also has installed surge protectors on his other equipment.
He is a ham radio operator and lives on a hilltop with many antennas poking
up.
I suggested that he talk to an lightning protection expert and get some more
advice.
He has been into ham radio for a long time and does well in national and
world contests, actually coming in 1st in world several times and is used to
seeing lightning while doing these contests on hills and mountain tops.
Now maybe he will not be in the higher standing for lightning strike
damage.



 
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w_tom
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Posts: n/a
 
      10-29-2007
On Oct 29, 12:08 pm, "Buffalo" <(E-Mail Removed)> wrote:
> I suggested that he talk to anlightningprotection expert and get some more
> advice.


How many GFCIs, smoke detectors, and clock radios were damaged? The
assumption was that everything without surge protectors were
damaged. In reality, anything damaged created a circuit from the
strike to earth. Nothing stops that current flow as some protectors
would have us believe. Things most easily damaged would have been
closer to that incoming surge.

Polyphaser is a benchmark that any ham radio operator should be
familiar with. Polyphaser discusses what provides protection.
Protection is not defined only by a protector:
http://www.polyphaser.com/technical_notes.aspx

Electrical Engineering Times has two articles entitled "Protecting
Electrical Devices from Lightning Transients" in the 1 Oct and 8 Oct
issues. This engineering discussion is completely about protection.
Therefore protectors are not discussed. Protectors do not provide the
protection. Protectors simply connect to protection. Those
engineering articles on protection (same in Polyphaser application
notes) discuss the only thing that provides protection - earth ground.
http://www.planetanalog.com/showArti...leID=201807127
http://www.planetanalog.com/showArti...leID=201807830
> Providing a flow path for the lightning current is central to
> effective lightning protection.


ARRL also discusses these concepts.

An industry professional solved lightning damage problems in a
Nebraska radio station. Did he install protectors? Yes. He
installed protectors where that 'whole house' protector would connect
surges to earth. How did he make that protection even better? He
enhanced the earthing as even described with numbers. See "Proper
Copper Grounding Systems Stops Lightning Damage at Nebraska FM
Station":
http://www.copper.org/applications/e.../nebraska.html

Where does surge energy get dissipated? Do you really believe a
plug-in protector will dissipate energy that even three miles of sky
could not stop? That energy must be dissipated somewhere. Dissipating
the entire surge is what a protector without earthing must accomplish.

Surge energy must be dissipated in earth where it does no harm. A
rather small and properly earthed protector can divert massive direct
lightning strikes to earth - without damage.

How effective is the technology? The technology (not found in plug-
in protectors) was proven even 100 years ago. Your telco switching
center connects to overhead wire everywhere in town. Bell System
analysis measured typically 100 surges during each thunderstorm. 100
surges and no damage to their computers? Why is your phone service
gone for four days while they replace that computer? Because the
computer must never suffer damage.

Telcos also use properly earthed 'whole house' protector on each
incoming wire. Protector must be located as close to earth as
possible and separated from protected electronics (typically up to 50
meters from electronics). A similar device is installed on every
subscriber line where wire enters the house. A protector does not
provide protection. That protector only connects surges to the
protection - earth ground.

How many engineering sources define and demonstrate effective
protection? Polyphaser. Electrical Engineering Times. The Nebraska
radio station. ARRL. The telephone system in every town. In every
case, direct lightning strikes are routinely earthed without damage
AND the protector must remain functional after that surge. The
technology is that routine. Products that perform effective
protection for AC mains are sold by Square D, Intermatic, Cutler-
Hammer, Leviton, Siemens, GE, and others. Only responsible
manufacturers sell these effective solutions. Technology and
protection is not found when a protector is located adjacent to
electronics.

 
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Buffalo
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Posts: n/a
 
      10-29-2007
w_tom wrote:
> On Oct 29, 12:08 pm, "Buffalo" <(E-Mail Removed)> wrote:
>> I suggested that he talk to a lightning protection expert and get
>> some more advice.

>
> How many GFCIs, smoke detectors, and clock radios were damaged?


None

> The
> assumption was that everything without surge protectors were
> damaged.


Sorry, wrong assumption.
All other electrical equipment not mentioned seemed to survive, including
all the GFIs,am-fm radios,MicroWave,Dishwasher,Disposal,Washer,Dryer, Dimmer
Switches,Refrigerator,Garage Door Opener, PhotoCell controlled
lights,VCR,satillite dish unit,etc.
I was just stating that because his ham radio,PC, answering machine were on
the same ciruit, but the PC was the only item on the surge protector. So,
perhaps the surge protector did just enough to help.

> In reality, anything damaged created a circuit from the
> strike to earth.


Maybe the surge protector put in just enough delay so that when the
answering machine and Ham appliance got fried, they diverted the rest of the
voltage spike to ground.

>Nothing stops that current flow as some protectors
> would have us believe. Things most easily damaged would have been
> closer to that incoming surge.


Yes, that is usually true.

> Polyphaser is a benchmark that any ham radio operator should be
> familiar with. Polyphaser discusses what provides protection.
> Protection is not defined only by a protector:
> http://www.polyphaser.com/technical_notes.aspx


Excellent reference. I will refer my friend to this, just in case he doesn't
know it already.

> Electrical Engineering Times has two articles entitled "Protecting
> Electrical Devices from Lightning Transients" in the 1 Oct and 8 Oct
> issues. This engineering discussion is completely about protection.
> Therefore protectors are not discussed. Protectors do not provide the
> protection. Protectors simply connect to protection. Those
> engineering articles on protection (same in Polyphaser application
> notes) discuss the only thing that provides protection - earth ground.
> http://www.planetanalog.com/showArti...leID=201807127
> http://www.planetanalog.com/showArti...leID=201807830
>> Providing a flow path for the lightning current is central to
>> effective lightning protection.


I will forward the above URLs to him also. Thank you.


> ARRL also discusses these concepts.
>
> An industry professional solved lightning damage problems in a
> Nebraska radio station. Did he install protectors? Yes. He
> installed protectors where that 'whole house' protector would connect
> surges to earth. How did he make that protection even better? He
> enhanced the earthing as even described with numbers. See "Proper
> Copper Grounding Systems Stops Lightning Damage at Nebraska FM
> Station":
>
> http://www.copper.org/applications/e.../nebraska.html
>
> Where does surge energy get dissipated? Do you really believe a
> plug-in protector will dissipate energy that even three miles of sky
> could not stop?


Of course not. Surge protectors 'may' help prevent damage from a voltage
spike

>That energy must be dissipated somewhere.


Doesn't a thermistor absord some of that energy when it slowly
'disintergrates'?
ie: voltage spike with low amperage

Yes, usually to ground, via a grounding wire or through a bonding wire or
through a grounding electrode conductor.

>Dissipating
> the entire surge is what a protector without earthing must accomplish.
> Surge energy must be dissipated in earth where it does no harm. A
> rather small and properly earthed protector can divert massive direct
> lightning strikes to earth - without damage.
>
> How effective is the technology? The technology (not found in plug-
> in protectors) was proven even 100 years ago. Your telco switching
> center connects to overhead wire everywhere in town. Bell System
> analysis measured typically 100 surges during each thunderstorm. 100
> surges and no damage to their computers? Why is your phone service
> gone for four days while they replace that computer? Because the
> computer must never suffer damage.
>
> Telcos also use properly earthed 'whole house' protector on each
> incoming wire. Protector must be located as close to earth as
> possible and separated from protected electronics (typically up to 50
> meters from electronics).


How did you arrive at that? I was under the impression that the incoming
telephone wire was protected right near where it entered the house and the
protection device was usually connected to a cold water pipe via a grounding
clamp.

> A similar device is installed on every
> subscriber line where wire enters the house. A protector does not
> provide protection. That protector only connects surges to the
> protection - earth ground.


I think sometimes it does that through a 'spark' gap.

>
> How many engineering sources define and demonstrate effective
> protection? Polyphaser. Electrical Engineering Times. The Nebraska
> radio station. ARRL. The telephone system in every town. In every
> case, direct lightning strikes are routinely earthed without damage
> AND the protector must remain functional after that surge. The
> technology is that routine. Products that perform effective
> protection for AC mains are sold by Square D, Intermatic, Cutler-
> Hammer, Leviton, Siemens, GE, and others. Only responsible
> manufacturers sell these effective solutions. Technology and
> protection is not found when a protector is located adjacent to
> electronics.


Is MeterTreater a responsible company in the above aspect?

Very informative reply. Thanks


 
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nobody >
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      10-29-2007
Plato wrote:
> Dan C wrote:
>> On Sat, 27 Oct 2007 03:11:04 -0500, Plato wrote:
>>
>>>> Everything was working fine for over a year, had a lightning storm and
>>>> after that the internet wouldn't connect. Here's what is interesting:
>>> Too bad you didn't have any surge protectors in line. Get some to avoid
>>> future problems.

>> A surge protector will do nothing at all to protect against a close
>> lightning hit. Nothing.

>
>
> Agreed.
>


Seconded. I've seen telephones that were burnt inside (open ringer coils
no less!) that were protected by hi-end telco suppressors. This was from
a lightning strike about a third of a mile away.
 
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Plato
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      10-30-2007
kráftéé wrote:
>
> Lightning goes it own way to the earth, so any protection is better
> than non at all...



When growing up, everybody said NOT to go under a tree in a
thunderstorm, but they never said why. Years later I learned that if
lightning hits the tree it instantly turns the sap/water in the tree to
boiling, thus exploding the tree.


 
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