Grounding and lightning.

  • Thread starter Thread starter Skybuck Flying
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Skybuck Flying

Hello,

Hopefully this will be my last question to "research" and determine if I
want to ground my hardware.

What happens if lightning strikes near the ground wire ?!?

(I have seen lightning strike closeby a couple of times so it's a realistic
scenerio).

Could this be a reason for people to unplug their systems ?!?

What if systems are not grounded ?!? Is the risk for equipment damage lower
when lightning strikes ?

If systems are grounded is their lightning strike danger for human
fatalities ?!?
For example: I touch PC chasis or something and boom lightning strikes...
could that kill me ?! ;) :) =D
Or perhaps it will even come at me through the air from pc to me ?! ;)

I guess the power room contains stuff to prevent such situations but are
they generally enough ?!?

I guess all this stuff needs to be checked by specialist which I might call
soon ;)

He gonna have a tough customer with me ! ;) =D

Bye,
Skybuck.
 
Skybuck said:
Hello,

Hopefully this will be my last question to "research" and determine if I
want to ground my hardware.
Click to expand...
Ground your ****ing hardware already, and shut up about it!
 
Skybuck said:
Hello,

Hopefully this will be my last question to "research" and determine if I
want to ground my hardware.

What happens if lightning strikes near the ground wire ?!?

(I have seen lightning strike closeby a couple of times so it's a realistic
scenerio).

Could this be a reason for people to unplug their systems ?!?

What if systems are not grounded ?!? Is the risk for equipment damage lower
when lightning strikes ?

If systems are grounded is their lightning strike danger for human
fatalities ?!?
For example: I touch PC chasis or something and boom lightning strikes...
could that kill me ?! ;) :) =D
Or perhaps it will even come at me through the air from pc to me ?! ;)

I guess the power room contains stuff to prevent such situations but are
they generally enough ?!?

I guess all this stuff needs to be checked by specialist which I might call
soon ;)

He gonna have a tough customer with me ! ;) =D

Bye,
Skybuck.
Click to expand...
Lightning goes where it wants to go.
No amount of grounding thru wire you can bend is gonna help.
DO NOT TOUCH anything when there's a lightning strike.
And ground equipment according to the manufacturer's instructions.
And yes, you worry too much.
 
Hmm...

I come across this message:

"Lightning and "Surge Protectors"

http://community.discovery.com/eve/forums/a/tpc/f/9701967776/m/7041960579?r=2791922579#2791922579

Message content:

"
I recently had to replace my computer due to a nearby lightning strike. The
computer was off but still plugged in. The surge protector was unaffected,
but now the computer will not boot up. The hard drive is turning, the LED's
are lit, but nothing from the comuter to the monitor. Even hitting the off
button has no effect. I'm guessing that stray currents got into the
motherboard and cooked something. Any ideas if the computer is toast or can
it be fixed?
"

Bye,
Skybuck.
 
Another interesting story:

"

When I worked several months in Bavaria, I lived in a small flat in a remote
village.
The power lines run from house to house on the roof. It happens very often
that this line is hit and destroys devices. The Villagers unplug everything
and leave the lights (bulbs, not CFLs) on to minimize the damage. But it
happens often that something wasn't unplugged and became destroyed.

Since I am an electronics engineer, the old lady who owned the house asked
why she never had any broken devices. Her neighbours often complained about
broken stuff, but she never had any problems. First, I couldn't explain it
until...:
One day I went down into the cellar to wash my laundry, I noticed a
transparent plastic cap in the sink. The old lady insists on operating the
machine since she never trusts anybody to do it correct. After she started
the washing machine I showed her this plastic cap. Se told me that it
belongs to the emergency light next to the fuse box. She had someone
installed it because she was afraid of a broken bulb and might fall down the
stairs. It was a small neon bulb as used in switches as indicator. She told
me that the cap of the light sometimes lands in the sink.
When I installed the transparent plastic lid, I noticed that glass of the
bulb was very darkened.
And this was the explanation. When a lightning hits the power line, the bulb
acts as a spark gap and limits the power surge in her house. The sudden heat
of the bulb blasts of that plastic cover. This emergency light acted as a
simple surge protector which helped protecting her devices! It was installed
between phase and ground (not neutral) and tripped the residual-current
device whenever it ignited during a power surge.
This thing was nothing but an "accidental" home-made surge protector!
"

Bye,
Skybuck.
 
Another interesting story, death included :):

"
Neither talking on a land line phone nor taking a shower increases the
chances of lightning directly hitting your house BUT, as yuandrew said, both
of these activities do increase your chance of injury or death should a
direct hit happen. In fact, 1 to 2 people a year are killed by lightning, in
the U.S. while talking on a wired phone inside a building. The number
injured is much higher. Wireless phones and cell phones are safe.
"

Bye,
Skybuck.
 
"Skybuck Flying" wrote in message

Hello,

Hopefully this will be my last question to "research" and determine if I
want to ground my hardware.

What happens if lightning strikes near the ground wire ?!?

(I have seen lightning strike closeby a couple of times so it's a realistic
scenerio).

Could this be a reason for people to unplug their systems ?!?

What if systems are not grounded ?!? Is the risk for equipment damage lower
when lightning strikes ?

If systems are grounded is their lightning strike danger for human
fatalities ?!?
For example: I touch PC chasis or something and boom lightning strikes...
could that kill me ?! ;) :) =D
Or perhaps it will even come at me through the air from pc to me ?! ;)

I guess the power room contains stuff to prevent such situations but are
they generally enough ?!?

I guess all this stuff needs to be checked by specialist which I might call
soon ;)

He gonna have a tough customer with me ! ;) =D

Bye,
Skybuck.


I would recommend for you to get a long metal rod, go outside on a stormy
night away from trees and hold the rod up as high as you can, then just
stand there and wait. You'll do us all a favor.

Shaun
 
Since I am an electronics engineer,
Click to expand...


This cannot be a story about you, because there is no way in hell that
someone as stupid as you are is an electrical engineer.
 
Hello,

Hopefully this will be my last question to "research" and determine if I
want to ground my hardware.

What happens if lightning strikes near the ground wire ?!?

(I have seen lightning strike closeby a couple of times so it's a realistic
scenerio).

Could this be a reason for people to unplug their systems ?!?

What if systems are not grounded ?!? Is the risk for equipment damage lower
when lightning strikes ?

If systems are grounded is their lightning strike danger for human
fatalities ?!?
For example: I touch PC chasis or something and boom lightning strikes...
could that kill me ?! ;) :) =D
Or perhaps it will even come at me through the air from pc to me ?! ;)

I guess the power room contains stuff to prevent such situations but are
they generally enough ?!?

I guess all this stuff needs to be checked by specialist which I might call
soon ;)

He gonna have a tough customer with me ! ;) =D

Bye,
  Skybuck.
Click to expand...

I run my PC gear on a double conversion UPS. Hopefully the UPS will
blow up before the PC gear does. I think the only solution is to
condition the power and hope for the best. Note that a standard ups
with some surge suppression built in is not the same as a double
conversion UPS. The double conversion UPS take the line to DC,
suppresses the hell out of noise on the DC (which is far easier than
suppressing on AC), then creates a true sine wave. This is one way UPS
is handled in data centers. The other way is to use PCs that take
48VDC rather than AC, and run the PCs off of a 48V battery bus that is
being floated. There are probably other schemes as well.

Note a double conversion UPS is noisy. It has fans. They are really
not designed for consumer use, but rather enterprise installations.

http://www.apcdistributors.com/whit... On-line vs. Line-interactive UPS designs.pdf
 
Skybuck said:
Another interesting story, death included :):

"
Neither talking on a land line phone nor taking a shower increases the
chances of lightning directly hitting your house BUT, as yuandrew
said, both of these activities do increase your chance of injury or
death should a direct hit happen. In fact, 1 to 2 people a year are
killed by lightning, in the U.S. while talking on a wired phone
inside a building. The number injured is much higher. Wireless phones
and cell phones are safe. "
Click to expand...

FWIW, I was talking on the phone once with a neighbor when lightening struck. We
both heard the CLAP, but she received a significant shock. Funny thing, but for
several days, her hearing was ultra sensative - she could hear really well.

I checked the wiring for the phone line coming into their house, and discovered
that when some plumbing work had been previously done, the ground wire for the
phone system had been removed from the water pipe at the hose bibb. That was why
she got shocked.
 
Bob said:
FWIW, I was talking on the phone once with a neighbor when lightening struck. We
both heard the CLAP, but she received a significant shock. Funny thing, but for
several days, her hearing was ultra sensative - she could hear really well.

I checked the wiring for the phone line coming into their house, and discovered
that when some plumbing work had been previously done, the ground wire for the
phone system had been removed from the water pipe at the hose bibb. That was why
she got shocked.
Click to expand...

I'd say, she was pretty lucky. It could have been a lot worse.

Paul
 
Since I am an electronics engineer
Click to expand...

Provide some certs, clown. I'd love to see who gave *you* a diploma.

Kinda sorta explains the whole thing. I did start college as an EE back
in 1968, but didn't finish the 1st quarter. "Uncle Sam" changed my
plans... but I did have about a 3.2 GPA for what time I did have.

"Unca Sam" (USAF) did teach me what I didn't know already, but I'd
already decided that I'd be happier as a tech.

It's quite funny how "engineers" get treated in hi-tech. Unless proven
otherwise, management won't let them touch tools, test equipment, or
even product. They have a qualified tech do that for them. I spent
thousands of hours playing "voice-controlled scope-probe
operator(VCSPO)" supporting engineers.

One of my favorite memories was doing prototype tech on a severely
complicated power supply for "Secure Voice Comm" for US Navy submarines
back in 1983. Things weren't(as usual in proto) going well, so I'd spent
about 30 hours of VCSPO with one particular engineer.
Said engineer suddenly got this funny "glazed eye" look, stood up, and
screamed

(drumroll)
"I designed THIS? It's a mind ****!!"
(20 seconds of dead silence, then applause (mostly vulgar))

I'm not knocking ALL engineers, but I've seen far too many that think
and act like SkyBuck. When they don't have a practical background to
work from, they drag out all the "oo-wee-oo" crap to explain it away.



--
"Shit this is it, all the pieces do fit.
We're like that crazy old man jumping
out of the alleyway with a baseball bat,
saying, "Remember me motherfucker?"
Jim “Dandy” Mangrum
 
Where did I write that...

If I did write that somewhere then it:

1. Either wasn't me.

or

2. I ment software engineer ! ;) =D

or

3. I was just having fun with my hardware ! ;) =D

Bye,
Skybuck =D

"Nobody > (Revisited)" wrote in message

Since I am an electronics engineer
Click to expand...



Provide some certs, clown. I'd love to see who gave *you* a diploma.

Kinda sorta explains the whole thing. I did start college as an EE back
in 1968, but didn't finish the 1st quarter. "Uncle Sam" changed my
plans... but I did have about a 3.2 GPA for what time I did have.

"Unca Sam" (USAF) did teach me what I didn't know already, but I'd
already decided that I'd be happier as a tech.

It's quite funny how "engineers" get treated in hi-tech. Unless proven
otherwise, management won't let them touch tools, test equipment, or
even product. They have a qualified tech do that for them. I spent
thousands of hours playing "voice-controlled scope-probe
operator(VCSPO)" supporting engineers.

One of my favorite memories was doing prototype tech on a severely
complicated power supply for "Secure Voice Comm" for US Navy submarines
back in 1983. Things weren't(as usual in proto) going well, so I'd spent
about 30 hours of VCSPO with one particular engineer.
Said engineer suddenly got this funny "glazed eye" look, stood up, and
screamed

(drumroll)
"I designed THIS? It's a mind ****!!"
(20 seconds of dead silence, then applause (mostly vulgar))

I'm not knocking ALL engineers, but I've seen far too many that think
and act like SkyBuck. When they don't have a practical background to
work from, they drag out all the "oo-wee-oo" crap to explain it away.



--
"Shit this is it, all the pieces do fit.
We're like that crazy old man jumping
out of the alleyway with a baseball bat,
saying, "Remember me motherfucker?"
Jim “Dandy” Mangrum
 
FWIW, I was talking on the phone once with a neighbor when lightening struck. We
both heard the CLAP, but she received a significant shock. Funny thing, but for
several days, her hearing was ultra sensative - she could hear really well.
Click to expand...

That is unusual. People that have been very close to a lightening strike
usually find that their ears ring for a couple of hours maybe longer and
take a while to recover. Our building with a large metal roof took a
direct hit that went down the phone lines - turned out later someone had
nicked the exterior copper lightning conductor.

All that was left was a charred blackened mess on the wall where the
phone trunking had been and into the switchboard. The switchboard girls
were very upset, in tears and initially quite deaf. Building lost power
too. Damage was mostly confined to the vertical path of the arc. It was
a very big bang for everyone in the building but must have been
absolutely terrifying in the small reception and switchboard room.
I checked the wiring for the phone line coming into their house, and discovered
that when some plumbing work had been previously done, the ground wire for the
phone system had been removed from the water pipe at the hose bibb. That was why
she got shocked.
Click to expand...

Local ground wire for a domestic phone?

I have once had a minor belt off my terrestrial TV roof aerial lead
whilst rewiring it to take a satellite dish feed. There was enough
static HT on it to light a neon screwdriver - a storm was coming but I
didn't know that at the time. Careless not to have checked first.

Regards,
Martin Brown
 
I'm know this happens at some places, but not anywhere I'd want to work.
Click to expand...

The last 10 years I was in IBM, technicians were more rare than hen's teeth.
There had been a steady downward path in that direction for the last 25 or so
years. It started with, "any engineer worth his pay can do technician work",
through "if I can hire one person, do I want an engineer or a technician" (see
above), to "there isn't any more work for technicians - you're all laid off".
Indeed, I've been specifically asked/told at interviews, "You can solder,
right? -- All of our engineers are required to have workable (if not
beautiful) soldering skills..."
Click to expand...

As long as they don't make me use that commie solder! I refuse, which gets me
out of working on manufacturing problems and customer equipment. ;-)
I can't help but think that any company like that is quite inefficient...
which usually means that (1) they're a government contractor or (2) they're in
a very "exposed" position, likely to be killed by their competition. Both are
not exactly the kind of places most really good engineers wants to spent their
careers...
Click to expand...

Nope. I wouldn't work there.
Check out the pictures on the cover of Jim Williams' book, "Analog Circuit
Design." Anywhere the engineers *don't* have benches that look a bit like
that, I'd be worried!
Click to expand...

I don't have a "bench". There are benches where I camp out, but it isn't in
any way assigned to me and I'm usually working between someone else's junk.
I'm really the only one who does any design anymore, too. The firmware types
work in their cubes/office.
 
I had an uncle who did EE at Boeing. During the interview process, he'd
reach into a drawer and hand his victim a soldering iron, business end
first, and say "here". Grabbing the 'ouch' end without hesitation meant
that the candidate would soon be politely ushered out the door, never to
work for him.
Click to expand...

Better; bump it off the table and see which way he moves.
 
I saw something falling off someone else's bench (out the corner of
my eye) once, and caught a hot soldering iron that had rolled off the
edge of the bench. It hurt like hell, for a week. I grabbed a tube of
pure silicon grease (W.W.II surplus Solenoid Grease) and smeared it on
the burnt skin before it could dry out and ended up with no scarring.
Click to expand...

There's the door. ;-)
 
I wasn't there for a job. I was delivering repaired equipment. The
'customer' was trying to do some repairs themselves, and as usual,
something went wrong. OTOH, if I hadn't caught that iron, they weren't
paying attention and it would have burnt down a three story building.
Click to expand...

Let it fall, then pick it up *after* you've figured out which end is the cold
end. ;-)
 
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