Is there some way to protect a house from lightning strikes? We got whacked
last week & have a lot of damaged electronic goodies. I don't want to go
through this again! It struck my 10 ft satellite dish & came into the house
& got into the mains panel. From there it went to every circuit in the
house. I have 2 GFI circuits in the house and they both tripped and nothing
on those circuits was damaged. That's why I asked about something that could
cover the entire house.
Several years ago I had my main panel upgraded to 200A, covered by
circuit breakers (original system was fuzes). Installer said the
above issue was the most important. After he drove in the rod and
connected the power system ground to it, he told me to get hold of the
phone company and the cable guys and insist that they relocate their
grounds to that ground.
Once done, previous problems I had had with lightning strikes taking
out TVs, etc., went away and I have not had that kind of a problem
YMMV, I guess
Your house should be protected from lightning strikes and this has
nothing to do with surges. Is your satellite grounded? I don't know
the codes but I am almost positive it should be. Everything outside of
my house is grounded, and even on my last house which was build in
1920s. That way it would have never entered your house. There is NO
protection from a direct lightning strike. That the GFCIs tripped was
probably from noise due to the hit, but not likely a real hit. In fact
you probably got a sympathetic stroke anyway, a direct hit would have
blown some 8hit up. Including yourself.
How do you know where the stroke came in and how it travelled?
Lightning just wants to get to earth, surprising it would get to the
main box, then go back into the house again.
Anyway, that dish should probably have a ground line on it. Tying to
ground outside of the house.
A whole house surge protector is an excellent idea, but it sounds like
it wouldn't have helped in this case. The surge protector will protect
against most lightening induced surges on the incoming AC, but if it
enters the house elsewhere, it won't stop it. Like others have
suggested, I'd check the grounding/installation of the dish.
Three electric wires enter your house. One connects to
earth ground. How are the other two wires earthed? Not
earthed if a 'whole house' protector is not properly
installed. Two of the three AC electric wires (not earthed by
a 'whole house' protector) carry destructive surges (such as
lightning) into a building; finding earth ground,
destructively, via household appliances. In most homes, only
one of three AC electric wires is earthed. In some homes,
even that ground is missing or compromised.
It has been routine for generations to earth direct
lightning strikes without damage. However homes were not
designed to protect transistors. Unfortunately we still build
new homes without superior and inexpensive earthing. So we do
the best we can as an after thought. Still that after thought
is sufficient to earth direct strikes without damage. But
that means every wire - all three electric - both telephone
wires, etc - make a short connection to the same earth ground
either by direct connection or via a surge protector.
"CL (dnoyeB) Gilbert" wrote:
Well the electrical code should be such that these 3 wires are always
present together. A strike is going to prefer the 'earthed' wire over
the ones not earthed. Even if you install a surge device, the 'earthed'
wire is still going to be the easier path to ground.
Its a surge protector, not a lightning protector. It will protect you
to some degree from a borked transformer or some odd occurance likely
generated local to your neighborhood (Frankenstein). It will absolutely
not offer any protection from lightning strikes, direct or indirect.
Lightning will utterly obliterate a surge protector.
On Thu, 07 Jul 2005 10:42:05 -0400, "CL (dnoyeB) Gilbert"
20 years of experience here in Florida with hundreds of customers and
their computers seems to dispute that. We have more lightning strikes
on a typical summer afternoon than most of the country sees in a year.
Effective grounding and transient protection works.
Whole house protection is a standard option these days
for the Mains boxes and is readily avaliable. However,
that does not negate the need for surge protection on
sensitive equipment like computers: It's a different
level of protection and also surges are created within
the house environ also.
NOTHING will protect against all lightning strikes,
especially if they are close by.
a lightning surge yesterday. It popped the UPS on so I
know it was a good hit, and the UPS shows it as a surge
> 132Vac; and the printer quit working. Turns out I
plugged the printer directly into the wall instead of
one of the surge outlets. Dumb! ;=(.
Don't have a whole house protector but think it's a good idea. I do use
those strip surge protectors on just about everything. One time I had two in
series and we caught a powerline overload and the first protector basically
exploded, burned the carpet it was sitting on but a police scanner,
shortwave radio and tel answering machine connected to it survived. The
second surge protector which had a computer and printer hooked to it went
These were standard "metal cased" MOV (metal oxide varistor) 5 outlet
surge protectors. I'm convinced we would have had a house fire if the surge
protectors had been encased in a plastic rather than metal. RM ~
When an MOV protector fails catastrophically, then it was
grossly undersized. It operated in a region not defined by
its manufacturer - in violation of the part's intent. But if
a power strip protector is undersized, then the homeowner will
know of the surge. That promotes more sales of undersized
protectors that really don't provide the protection and, as
Rob Mills demonstrates, can even create a house fire.
The effective protector earths a surge; and the homeowner
never knows it happened.
Protectors that provides effective protection are located
close to earth ground AND are properly sized. This is called
a 'whole house' protector. Where it is located? Not on a
pile of papers on a desk, or behind the furniture, on a rug,
or within dust balls. Just more reasons why plug-in
protectors (that cost so much money) are so ineffective.
Rob Mills wrote:
===> Undersized how? They're rated for x joules, more
than that causes the MOVs to conduct, until they open
the ckt. If you mean undersized to protect against
monsrous surges, OF COURSE!! The sentence means
It operated in a region not defined by
===> How do you know that?
===> What does that mean?
then the homeowner will
===> It's more likely the homeowner will NOT know of
the surge, since the vast majority of the time an MOV
fails OPEN once it conducts, he may not even know it
was surged unless it has indicators for functionality.
That promotes more sales of undersized
===> NO surge protector can protect beyond the number
of joules it's rated at, and it would very UNlikely to
have started a fire if nothing else in the house was
bothered. That surge, if it really happened, was large
enough to jump the gaps of the MOVs once they opened
up, and thus was capable of jumping many other gaps.
Sometimes though, a protector CAN sacrifice itself for
the equipment, which sounds like what happened, but ...
it wouldn't have started a fire unless it was sitting
inside a pile of tinder that sparks could have ignited.
The plastic would nto have melted or other equipment
would have been damaged. Black stuff only indicates
spark, not flame.
===> No, protectors do much more than that; they are
wye-connected varistors usually with inductive walls to
keep the lines within safe ranges of each other whether
it's earth or hot to neutral or ... and so on.
===> What the hell do you mean by "properly sized"?
And what the heck does "close to ground" mean anyway?
You have no idea what you're talking about, do you?
This is called
===> Wrong, proton breath; they are quite effective and
useful and are recommended for very good reasons. I
hope you aren't using any and that you shortly suffer
several power and phone line lightning hits within 5
miles of your home or less, preferably the transoformer
you're fed from. You're a moron in this area.
So, uhhh, just where is it located, by the way? Do
you even know?
MOVs don't open the circuit. Even grossly undersized power
strips that have vaporized MOVs still connect an appliance to
AC mains. Where is this disconnection that Pop claims? It
does not exist.
A vaporized MOV operates outside of what the manufacturer
has intended and designed. Pop, if he had used facts rather
than post insults, would have first read those MOV datasheets
rather than learn from a BestBuy salesman.
Effective 'whole house' protectors install sufficient
joules. The owner never knows a surge exists AND the protector
remains functional. Power strips that are undersized will
vaporize leaving the appliance exposed to that surge. Then
the naive will recommend them and buy more useless protectors
at tens of times more money per protected appliance.
The naive will declare, "the protector sacrificed itself to
save my computer." Protection already inside the adjacent
computer saved that computer. The surge was too small to
overwhelm internal computer protection. But the same tiny
surge vaporized an undersized, overpriced, and ineffective
protector. Why put sufficient joules inside a protector when
less joules means Pop will recommend it?
If MOVs worked as Pop claims, then removed MOVs (same as
vaporized MOVs) would cause the power strip to stop working.
Reality: even the OK light remains illuminated after all MOVs
Why do power strips with vaporized MOVs still provide power?
Because they do not operate as Pop has posted.
Meanwhile code demands that all surge protectors not create
flames even if operated beyond its specs. Pop instead tells
us that "That surge ... was large enough to jump the gaps of
the MOVs once they opened up" Therefore a fire is
acceptable? When MOVs vaporize, the spark can continue
jumping across the vaporized MOV. That can mean fire. MOVs
are not designed to operate open circuited and are not
designed to vaporize. MOVs that vaporize - go open circuit -
can even create house fires. Why? Because the protectors was
so grossly undersized; too few joules.
Learn from what Rob Mills has posted. The last place you
want a grossly undersized power strip protector is on a desk
full of papers, in dust balls behind furniture, or on a rug.
Some pictures demonstrate the problem with grossly undersized
And finally: http://www.rbs2.com/fire.htm
Funny. That is not how Pop said they work. Funny. Pop
would even call plug-in protector house fires acceptable when
the surge is too large. Funny. He is so knowledgeable that
he insults rather than provide numbers, science concepts, or
citations. Worry about those grossly undersized power strip
protectors as even Rob Mills demonstrates.
MOVs conduct until the heat causes them to BECOME an
open circuit! I haven't seen anyone say the CREATE an
That's nonsensical crap above. It means nothing. You
obviously not only don't know much about the subject
and your reading comprehension appears to be even
"INSTALL JOULES"? Do you even know what a joule IS,
or what an equivalency might be? You don't "install"
The owner never knows a surge exists AND the protector
Sometimes. And sometimes everything works fine, but
the MOVs have done their job and BECOME OPEN CIRCUITS,
which will no longer have a knee voltage at which they
begin to turn on at.
That does NOT say they open the ckt; it says the
MOVs become an open ckt. Learn to read if you're going
to give advice. It would also help if you knew what
you were talking about.
Power strips that are undersized will
Like I said: What is "undersized"? HOW do you
under/over size a power strip? A "power strip"
literally does NOT have ANY surge protection. Your
terminology is all mixed up.
Possible; anything's possible. Cnn you give a specific
So will knowledgeable and experienced electrical
engineers and technicians and those with horizontal
experience records. "Naive" appears to be a word you
like, but not one that is descriptive in the context
you're using it in.
Protection already inside the adjacent
NOT if the surge protection clamped the surge down to
usable levels. It's also possible after such an event,
that the "protection" inside the computer (it's
actually in the power supply and telephone connection
ckts, by the way) could concievably be no longer in
existance. The MOVs could easily have also done their
job, and been blown before the "power strip" clamped.
You'd have to know the knee voltages and the clamping
times to make such a statement as you' ve tried to
The surge was too small to
HOW was it undersized? Are you aware of the joule
ratings used in most PC supplies? And those in the so
called "power strips"? I am, and I've evaluated and
repaired a LOT of them. THEN you have to go further
and consider CMOS damage, whether it's lost ITS
protection, and so on.
Why put sufficient joules inside a protector when
You don't PUT JOULES INSIDE a protector!
Of COURSE, you idiot! This is getting comical, and
rather pathetic, so I'm going to write you off as a
troll and you'll not hear further from me until/unless
you find something sane and sensible to say. Your
record is pathetic and you are a dangerous person to
They operate EXACTLY as I said.
This is getting comical, and rather pathetic, so I'm
going to write you off as a troll and you'll not hear
further from me until/unless you find something sane
and sensible to say. Your record is pathetic and you
are a dangerous person to rely on.
You're a troll.\\
<snip some extremly rude stuff>
Most of the posts I have read here are very friendly. What is your problem?
Is it because it's Usenet and no one knows who you really are? Pop, someday
you may find out that things are not so cut and dried as they may seem to
be to you. Life (facet) is to short and what we hold dear we hold near.
Good luck with your struggle Sir.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.