Should I buy a new motherboard if lightning hit my computer?

[w_tom]

Cordless phone base station damage occurs with a lightning
strike to AC mains. The phone line already has a 'whole
house' protector installed free by the telco. Destructive
lightning seeks earth ground. Incoming on AC mains, down the
street, into household AC electric, through cordless phone
base station, out on phone line through 'whole house'
protector to earth ground. Defined is a complete circuit
necessary to have damage.

Every incoming utility wire (and that includes cable) must
connect to single point earthing before entering the
building. Damage is when lightning found earth ground
destructively through that portable phone base station.
Damage avoidable had a 'whole house' protector been installed
and properly earthed on AC mains. Two sources of effective
protection are in Home Depot (Intermatic) or Lowes
(Cutler-Hammer and GE). Other responsible manufacturers of
effective protectors (with necessary earth ground connection)
are Square D, Levition, Polyphaser, and Siemens.

 

[Geoff]

If lightning use gas line to find earth ground, then your

building has serious earthing problems.

My house was built in 1994 and the gas company has been out to pressure test
the line, etc. They made no mention of what you said.

The lightning appears to have struck in the street because about 4 houses
were affected.

I can not explain everything since my cable modem was blown but the cable
set top boxes were completely unaffected.

My ups does claim a certain amount of surge protection with an internal
circuit breaker and I feel better having it sitting between my computer and
the wall outlet. Did any of it protect my computer? I don't know except
nothing in my computer has a direct connection to anything external (pc to
ups to wall outlet, pc to router to cable modem to cable outlet, etc.).

-g

 

[Geoff]

Notice the smoke detectors and bathroom GFCIs that

were also protected by the same UPS? Must be if they were not
damaged ... or the rationalization that the UPS /surge
protector did anything is only speculation not based in
facts.

I am talking about a ups for my computer only, not for the house.

After the lightning struck, all the circuit breakers in my fuse box popped
and the circuit breaker in my ups popped.

What was explained to me is lightning can do strange things, like why did it
blow out my cable modem but none of the tv set boxes?

I asked the gas company and the electric guy who came out but they told me a
lot of stories and said it is not explainable.

-g

 

[David Maynard]

I am talking about a ups for my computer only, not for the house.

After the lightning struck, all the circuit breakers in my fuse box popped
and the circuit breaker in my ups popped.

That one would seem to have been closer than the 'typical', to induce
surges heavy enough to pop every breaker, or, equally likely, the power
company has been remiss in maintaining their pole protection devices and/or
the one at your power entry.

What was explained to me is lightning can do strange things, like why did it
blow out my cable modem but none of the tv set boxes?

First thing to blow protects the rest (if it shorts, as opposed to being
blown open). A, uh, 'one time use' and expensive surge protector.

I asked the gas company and the electric guy who came out but they told me a
lot of stories and said it is not explainable.

"Not explainable" means without going to more effort than one is willing to
put into it.

 

[Geoff]

I asked the gas company and the electric guy who came out but they told
me a

"Not explainable" means without going to more effort than one is willing to
put into it.

My gas line is grounded. The grounding is outside the house where the meter
and main feed is. What has been explained to me is with a direct hit, with
those kinds of voltages, the lightning can arc and jump around and that is
probably what happened.

The gas guy told me he grew up on a farm and a lightning rod took a direct
hit, flew off the barn, and was red hot. The lightning arced and burned
down the barn anyway.

--tc

 

[w_tom]

Using only what has been posted, lightning could have been
incoming on AC electric. Lightning seeking earth via four
homes. One good path on incoming AC electric is into
computer, through integrated NIC, out via cable and router, to
cable earth ground. TV cable boxes and computer DRAM both
were not damaged for the same reason. Both did not provide an
incoming and outgoing path through electronics; therefore no
damage.

SAme has been observed elsewhere. For example, at another
location, a VCR and TV, side by side, and connected to AC
electric and cable. Incoming on AC electric. But only one
was damaged. The appliance that made a superior path to earth
ground via cable performed as a very expensive and
unintentional surge protector. The other appliance with
better internal protection was not damaged.

There is no stopping, blocking, or absorbing surges as a
plug-in UPS hopes you have assumed. Franklin demonstrated in
1752 that protection is about shunting (connecting, diverting)
a transient to earth; before it can find a destructive path
through transistors. Typical UPS connects a computer directly
to AC mains when not in battery backup mode. So where is
protection? Protection is based on assumptions rather than
facts.

A UPS relay that switches to battery backup AND the circuit
breaker require tens of milliseconds to react. Surges destroy
electronics and terminate in microseconds - 1000 times
faster. Neither a relay nor circuit breaker - both too slow
- even claim to provide such protection. But they hope you
will assume. The UPS claims protection from a transient that
does not typically exist; citing a vague and subjective:
"surge protection". Meanwhile, it does not protect from
transients that typically damage electronics. It's called
lying by telling half truths; hoping you will make
assumptions; assume the UPS provides effective protection.
The UPS does not even claim such protection - while
connecting computer directly to AC mains.

Meanwhile, show me otherwise. Show me the manufacturer spec
that defines protection from each type of transient. Notice
those specs assume all transients are the same type. More
assumptions to promote protection that is not effective.

How does a surge protector work? Picture is a power strip
protector (that uses same circuit also found in plug-in
UPSes). Active components - MOVS - are removed. The light
still says the protector is OK:
http://www.zerosurge.com/HTML/movs.html

Even with MOVs removed, power strip still provides
electricity to appliance receptacles. The protection circuit
is not between appliance and AC mains as they hope you will
assume. Like a UPS, the power strip does not sit,
electrically, between AC mains and the computer. But they
hope you will make such assumptions. They hope you ignore the
most critical component in a protection system - earth ground.

Some manufacturers hope you keep making assumptions. Their
products are promoted by those who don't even know what a
surge protector does - myth purveyors. However, responsible
electrical manufacturers sell effective protectors.
Intermatic, GE, and Cutler-Hammer were cited from Home Depot
and Lowes. Other manufacturers are Square D, Leviton,
Polyphaser, and Siemens. Effective protectors with a
reputable name AND that provides a connection to single point
earth. A connection that should be 'less than 10 feet'.

In multiple paragraph are reasons why that UPS is not
effective protection. Its function is to protect data from
blackouts and extreme brownouts; not surge protection. Why
some things are damaged whereas others are not was also
explained. Lightning is not capricious. But many (including
gas line repairmen) sometimes forget even what was taught in
elementary school science about lightning. Lightning damages
some things and does not pass through other things for
specific reasons.

Four houses suffered damage when lightning made a direct
connection through household appliances to earth. Damage from
direct strikes. Homeowners avoid such damage by diverting a
transient to earth before it can enter the building.

Solutions can be obtained in Home Depot, Lowes, and most
electrical supply houses. Never saw an effective protector in
Sears, Kmart, Radio Shack, Staples, Walmart, Circuit City,
CompUSA, or Best Buys. Ineffective protectors are easily
identified: 1) No dedicated connection to earth ground and 2)
manufacturer avoids all discussion about earthing.

To understand what was damaged, to predict possibly
overstressed components, and to avoid future damage; find
paths both incoming and outgoing to earth. Avoid future
damage why earthing those incoming paths at the service
entrance. Again, even Ben Franklin demonstrated the concept
in 1752.

 

[w_tom]

...
The gas guy told me he grew up on a farm and a lightning rod took
a direct hit, flew off the barn, and was red hot. The lightning
arced and burned down the barn anyway.

Typical example when lightning rods are not properly
earthed. Proper earthing mean negligible energy is dissipated
at rod and on earthing connection. But if the connection is
highly resistive (poorly installed), then significant energy
can create destructive results.

 

[David Maynard]

me a



My gas line is grounded. The grounding is outside the house where the meter
and main feed is. What has been explained to me is with a direct hit, with
those kinds of voltages, the lightning can arc and jump around and that is
probably what happened.

Sure it can. Does all the time. But you can diagnose from the trail of
charred remains

I didn't mean to suggest they were 'lazy'. It's usually not worth the
effort to do an extensive post mortem when the purpose is mainly curiosity.
Not to mention that isn't really their job. Their job is to fix what's broke.

The gas guy told me he grew up on a farm and a lightning rod took a direct
hit, flew off the barn, and was red hot. The lightning arced and burned
down the barn anyway.

We had a saying that if God wants the barn to burn down then, by golly, the
barn is going to burn down.

 

[David Maynard]

w_tom wrote:

Franklin demonstrated in
1752 that protection is about shunting (connecting, diverting)
a transient to earth; before it can find a destructive path
through transistors.

Picked up the transistors for his demonstration at ye olde Radio Shack, no
doubt.

 

[Ed Medlin]

w_tom wrote:



Picked up the transistors for his demonstration at ye olde Radio Shack, no
doubt.

I had a strike a year or so ago that was kind of unique. Before any strike
at all I could hear buzzing and smelt ozone. All my breakers popped first
and after the strike I had a century old oak tree blown completely out of
the ground 20-30yrds from my home. My circuit breaker box was toast. I
didn't have any electronic damage amazingly. The electritian that replaced
my box and breakers said something about "positive" lightning. I had not
heard about this before. Whatever it was, I don't want it again.......

Ed

 

[James T. White]

I had a strike a year or so ago that was kind of unique. Before any strike
at all I could hear buzzing and smelt ozone. All my breakers popped first
and after the strike I had a century old oak tree blown completely out of
the ground 20-30yrds from my home. My circuit breaker box was toast. I
didn't have any electronic damage amazingly. The electritian that replaced
my box and breakers said something about "positive" lightning. I had not
heard about this before. Whatever it was, I don't want it again.......

If that was "positive lightning", I shudder to think what kind of damage
"negative lightning" would have done!

 

[James T. White]

There is no stopping, blocking, or absorbing surges as a
plug-in UPS hopes you have assumed. Franklin demonstrated in
1752 that protection is about shunting (connecting, diverting)
a transient to earth; before it can find a destructive path
through transistors.

While I don't disagree with your conclusion, your assertion would mean
that old Ben was a fortune teller since the transistor wasn't invented until
almost 200 years later.

 

[David Maynard]

While I don't disagree with your conclusion, your assertion would mean
that old Ben was a fortune teller since the transistor wasn't invented until
almost 200 years later.

If his conclusion were valid it would be by pure chance rather than any
scientific reasoning because a transistor and an 18'th century building
have virtually nothing in common.

An electronic device will not be damaged if there is no damaging electrical
potential across it and while 'shunting to earth' is usually a good place
to start it's also often insufficient and in some cases unnecessary, if not
impossible, with aircraft electronics being one example (would be one hell
of a ground rod, eh?).

 

[David Maynard]

I had a strike a year or so ago that was kind of unique. Before any strike
at all I could hear buzzing and smelt ozone. All my breakers popped first

Sounds like one of those "they're heeeeere" kind of moments =:O)

The pre-strike event shows the fallacy of thinking that 'earth' here is the
same as 'earth' over there during a lightning strike, or even before. Earth
potential in your immediate area was elevated but since the power grid is
referenced to a 'different' earth 'over there' too it created a surge
popping the breakers.

During the strike, though, an open breaker is nothing for the lightning to
arc over. After all, it just traveled from the clouds to ground so a half
inch isn't going to get in the way. They just acted like spark gaps trying
to 'earth' your earth, till they fused or exploded.

and after the strike I had a century old oak tree blown completely out of
the ground 20-30yrds from my home. My circuit breaker box was toast. I
didn't have any electronic damage amazingly. The electritian that replaced
my box and breakers said something about "positive" lightning. I had not
heard about this before. Whatever it was, I don't want it again.......

If it was a positive lightning strike then you had a real baddie because
they're 6 to 10 times more powerful that the more common (95%) negative
lightning.

 

[Ed Medlin]

Sounds like one of those "they're heeeeere" kind of moments =:O)

The pre-strike event shows the fallacy of thinking that 'earth' here is
the same as 'earth' over there during a lightning strike, or even before.
Earth potential in your immediate area was elevated but since the power
grid is referenced to a 'different' earth 'over there' too it created a
surge popping the breakers.

During the strike, though, an open breaker is nothing for the lightning to
arc over. After all, it just traveled from the clouds to ground so a half
inch isn't going to get in the way. They just acted like spark gaps trying
to 'earth' your earth, till they fused or exploded.


If it was a positive lightning strike then you had a real baddie because
they're 6 to 10 times more powerful that the more common (95%) negative
lightning.

That would explain the old oak tree with it's entire root system out of the
ground........ My lights went out and the breakers were popping before
the actual strike took place, or maybe the whole event actually took that
long.

Ed

 

[w_tom]

The actual event would have completed before you even heard
it. Circuit breakers don't pop due to lightning. The surge
completed in microseconds. Milliseconds of excessive current
are required to trip a circuit breaker. Lightning is
microseconds. So what tripped circuit breakers?

Its called follow-through current. Lightning permitted
inside the building has constructed new electrical paths - as
lightning also constructed an electrical path through 3 miles
of non-conductive air. Those conductive paths remain after
lightning has come and gone. Those new (temporary) electrical
paths - also called a short circuit - would cause circuit
breakers to trip.

A direct strike to an oak tree could be a direct strike into
the building - which is why a building's earthing must be
single point. Or the same strike that also hit a tree could
have also been forking first into nearby AC electric lines.
Either way, damage and circuit breaker trips would have been
due to a direct strike that entered the building.

 

[David Maynard]

That would explain the old oak tree with it's entire root system out of the
ground........ My lights went out and the breakers were popping before
the actual strike took place, or maybe the whole event actually took that
long.

Ed

Depends on how long you mean. The typical lighting strike event itself is a
1/4 of a second or so.

That you had time to 'hear' a buzzing sound, smell ozone, and take notice
that lights and breakers tripped suggests to me you were witnessing
pre-strike effects. In particular, it would seem to be consistent with
ground charge before cloud leaders and ground streamers connected up
forming the strike path.

 

[Ed Medlin]

That would explain the old oak tree with it's entire root system out of

Depends on how long you mean. The typical lighting strike event itself is
a 1/4 of a second or so.

That you had time to 'hear' a buzzing sound, smell ozone, and take notice
that lights and breakers tripped suggests to me you were witnessing
pre-strike effects. In particular, it would seem to be consistent with
ground charge before cloud leaders and ground streamers connected up
forming the strike path.

It was probably only a couple of seconds before I saw the strike after the
pre-charge stuff was going on. Time enough for my dog to bark...... It
seemed longer, but that is not unusual when something like this happens. The
amazing thing about it all is that all my home theater equipment and
computers survived without any problems. I guess the breaker box demolition
helped there. Living here on the high plateau of the Ozarks, we are used to
a lot of bad storms but this strike was, well, just different. I have lost
trees before, but they were usually split at the trunk or topped out by the
lightning and not exploded out of the ground.......

Ed

 

[digisol]

Not reading all but the initial post and having seen a genuin
lightening strike that hit a house next door less than 30 feet awa
from where my mates and I were sitting, the sound and flash is abou
as loud as a 6" artillery round fired in your garage, instant an
very very loud, similar to someome sneaking up behind you with
shotgun, you will nearly crap your pants, at least spill your bee
while ducking for the ground, we did

The fuses being tripped instantly show they did their job and shoul
have stopped any household electrical goods damage, unless the strik
was direct to the house external wiring, if there was an indirec
charge via humidity / rain in that case most things may still be OK

If the system still works your lucky and there will be no drama tryin
it, most should know to have their PC's wired to the house with bot
surge protectors and overload switches which will protect most gea
but for a direct strike where many thousands of volts will jump 6 o
more feet making a surge protector rather useless and a PC somewha
fried like a burnt chip..

Don't confuse surge protectors with overload protectors and eart
leakage trip switches, all very different items and all should b
used on every house with extra protectors on the PC and every bit o
PC gear attached to it like printers, scanners etc and any othe
electrical equipment, although if your insured all the electrica
gear will usually be covered, fridge, TV, PC, sterio, etc.

If your house wiring is actually hit directly you will know all abou
it, real quick

 

[w_tom]

Conclusions based upon speculative assumptions. For
example, fuses and circuit breakers take milliseconds to trip
/ open. The lightning strike completes in microseconds.
Fuses don't trip or open fast enough to protect electronics.
Furthermore, will a fuse stop what 3 miles of sky could not?
Of course not (even defined by a voltage rating stamped on
each fuse).

Fuses and circuit breaker trip after damage has occurred -
to protect humans from that now damaged electronics /
electrical system. However many somehow know circuit breakers
and fuses are to protect household electrical goods - without
first learning basic electrical concepts or noticing why a
fuse has a voltage rating.

Same for a myth so often promoted on retail store shelves.
They hope you assume the product will somehow stop, block, or
absorb what even 3 miles of sky could not. Ineffective
protectors - sold at extravagantly high prices - hope you will
assume.

Meanwhile, the telephone company has a $multi-million
computer connected to overhead wires everywhere in town.
Clearly, a telco must disconnect their computer - disable your
phone service - during every thunderstorm to protect that
computer. OR spend one full week every year replacing your
computer. Which week did you have no phone service for 5 days
everywhere in town? The telco installed effective
protectors. Effective protectors don't even try to stop
destructive surges. The phone company does suffer direct
lightning strikes without damage using protection proven since
the 1930s. Protection that shunts or earths.

It is normal to suffer direct strikes and not suffer
damage. TV and FM radio equipment atop the Empire State
Building do that without damage about 25 times every year.
Same for commercial radio stations, cell phone towers, high
voltage AC electric transmission lines, 911 emergency response
systems, etc.

Many have posted that somehow protection means stopping or
blocking lightning. It's a myth. Plug-in protectors and
UPSes hope you will believe that myth. Meanwhile, effective
protectors for AC electric are sold with names of responsible
electrical manufacturers - Square D, Leviton, Intermatic,
Siemens, Cutler-Hammer, Polyphaser, and GE. Effective
protectors can be purchased in Home Depot, Lowes, and most
electrical supply houses. Ineffective protectors are found in
Staples, Sears, Radio Shack, Walmart, Circuit City, Target, or
the grocery store. The latter hope you will promote half
truths to excessive money on their products.

Fuses and circuit breakers don't protect household
electrical goods. The protector is only as effective as its
earth ground - a concept that even Ben Franklin demonstrated
in 1752. A concept, taught in elementary school science, that
ineffective and grossly overpriced protector manufacturers
hope you will forget. Lightning seeks earth ground. The
effective protector is only as effective as its earth ground -
which is not available on a plug-in UPS or power strip
protector. Effective protection from direct strikes is
shunting - not stopping a direct strike.

The above only discusses secondary protection. The homeowner
should also inspect household primary protection:
http://www.tvtower.com/fpl.html