I am completely befuddled why one cannot tell the difference
between a pointed verses a blunt lightning rod.
Next, what does CE - a safety standard - have in commmon
with something completely different - transient protection?
The UK standard for transient protection is (if I remember)
BS6651. Meanwhile, damage from lightning storms can occur
easeier in the UK. Other nations routinely install and
properly earth a 'whole house' protector on every incoming
phone line - for free. Same technique that also protects UK's
"£multi-million telephone switching computer" from damage
during lightning storms - with inexpensive and so effective
solutions. Phone line protection being so inexpensive and so
effective as to be standard in North America.
So, yes. Without meeting basic earthing requirements even
in BS6651, then UK residents would routinely suffer totally
unnecessary damage. A classic example of homes still not
constructed as if the transistor exists. A classic example of
electronics damage is directly traceable to human failure.
Dave Liquorice would have a dead network card (whose specs
would declare something like 2000 volts protection) because a
transient overwhelmed that 2000 volt NIC internal protection.
Just another example of why 'whole house' protection system is
installed - so that NIC protection is not overwhelmed. But
again, one need not trust me. Voltage necessary to overwhelm
NIC protection is provided on NIC's data sheet. Details
provided in that BS6651 standard. Just another example of why
one should first learn the numbers before wildly assuming
nothing can protect from lightning.
Meanwhile a classic example of semiconductors that meet (in
this case) 8,000 volt and 15,000 volt transients without
damage. But again, one need not trust me. Learn the numbers.
An example of learning numbers before wildly speculating:
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/4301
Fundamental to all this is a so well proven concept.
Protection is only as effective as its earth ground.
Dave Liquorice wrote:
...
You still have not answered the direct question on the defintion of
"blunt".
...
********. *Some* integrated circuits have limited protection from ESD,
without it you can't handle 'em without damage but your average signal
diode, transistor or other components do not.
Do not confuse the CE marking with lightning protection. CE marking is
purely down the abilty of the kit to reject and not produce
interference. On the rejection side the field strengths are minimal
compared to those surrounding a lightning strike.
If electronics is so well protected can you tell me why I have a dead
network card here? It died when there was a lightening strike 300
yards away.
...
No, but when ever there is a storm round here the number of telecoms
vans out and about increases noticeably. And again you are talking
"£multi-million telephone switching computer" (what only one?), that
is also a critcal part of the countries infra structure, not a bit of
cheap consumer electronics.
...
Explain my blown network card then please? The strike was several
hundred yards away with no physical connection between it and the
strike.