Demonstrated is that isolation protection existing inside
many appliances was sufficient to protect those appliances.
Sounds like you spent maybe $400 on plug-in surge protectors
and still had surge protectors fail.  Unacceptable.  But then
take a $3 power strip (retail) from Home Depot or Walmart,
remove the circuit breaker, then install some $0.10 parts and
sell it as a $20 plug-in surge protector.  Plug-in surge
protector are that profitable - and that undersized.  My
install sufficient joules when they are not even selling
effective surge protection?

  At $20 or $50 per protected appliance, you spent too much.
"Whole house" protectors typically cost about $1 per
appliance, must be sufficiently sized to remain fully
functional, and must result in no appliance damage.  'Whole
house' is how surge protectors were effectively installed even
in the 1930s - and are based upon principles demonstrated by
Ben Franklin in 1752.

  But here is the fact that those plug-in protectors must have
you not hear.  A surge protector is only as effective as its
earth ground.  They don't stop, block, or absorb surges.  They
only shunt - short all wires together during a surge.  If not
connected less than 10 feet to central earth ground, then
where do they shunt - dump - the surge?  Through a computer
modem?

  Reality: appliances are rated to withstand 1000s of volts.
That internal protection is compromised if you have not
earthed a surge before it can enter the building. Once inside
a building, the surge will seek many destructive paths to
earth ground through appliances. Appliance damage is so
avoidable as to be considered human failure.  That central
earth ground must be the building's best grounding.  But since
plug-in manufacturers are not selling effective surge
protection, then they avoid all discussion about earthing.
Why talk about earthing when they don't provide the essential
dedicated connection to earth ground?

  Home Depot sells two minimally sized 'whole house'
protectors - Intermatic EG240RC and Siemens QSA2020.  Both
cost about $1 per protected appliance.  Others are more
expensive because they provide even higher joules ratings
(joules determines a surge protectors life expectancy).  But
this cannot be avoided.  A surge protector is only as
effective as its earth ground - which ineffective surge
protectors avoid mentioning.

John Korb wrote:
> About 10 years ago I had some damage from a nearby lightning strike.  IIRC
> I replaced about 17 surge suppressors, with 4 or 5 (the most expensive
> ones) surviving and still providing protection.  At the time I had
> only one major (expensive) device not plugged into a surge suppressor - > an HP 150B - and it survived - no damage.  A TV set (with rabbit ears
> for the antenna) plugged into a $20 surge suppressor had a blown fuse
> and blown power supply.  Homeowners insurance (minus the deductible)
> covers the repairs.
>
> About 18 months ago an underground power cable was severed, and the
> resulting surge caused 4 or 5 surge suppressors to fry.  Only one
> device was damaged - a PC.  The power supply was A-OK, but the
> motherboard and CPU were both fried.  All other components in the PC
> were unaffected, and are still in use (including the power supply) -
> I just replaced the MB and CPU.

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