On Mar 6, 6:31*pm, westom wrote:
On Mar 6, 11:50 am, "
wrote:

It certainly may, but I would not count on it being 100%
effective and would not be surprised if there
were somedamageto AC appliances by a massive
direct lightning hit to a house.

*The poster asked about parameters that make a protector effective.

Actually, the poster didn't ask that at all.


Protection is always and only about where those hundreds of thousands
of joules dissipate. *Always. *Joules that a protector can absorb are
not a relevant parameter. *Important is its current rating. To remain
functional even after a direct lightning strike.

Of course how many joules a protector can withstand
is relevant. If protector A can take 3X the energy in
joules of protector B, than it will potentially survive surges
that A cannot. I could design a surge protector that
will survive your 50,000 amp requirement at 500 volts
for 100 nano seconds. It will however have a very low
joule rating of 2.5 joules because the time duration is
ridiculously short. On the other hand, I could design
a 20,000 amp one that will handle those amps
for 10 microseconds, which would be 100 joules.
Which one would you rather have? In reality the specs
tend to track each other. A surge protector with a
higher amp rating will tend to have a higher joule
rating as well. But you can't dismiss either amps
or joules as meaningless.

As a side note, let's not go down the "absorb" strawman
that you so cherish. We all know that almost all
the energy is flowing to ground. The above energy
rating in joules is what gets dissipated in the surge protector
because it is not a perfect conductor and hence has
a finite resistance.




* We routinely suffered direct lightning strikes without damage to
anything. *We properly installed what absorbs hundreds of thousands of
joules. *And connect a protector low impedance (ie 'less than 10
feet') to that solution. *Sorry that reality, micky's question and
RBM's answer makes you so angry. That anger also does not answer
relevant questions.

Neither the question nor RBM's answer made me angry.



* *A request was for relevant parameters.
*A typical lightning strike
is 20,000 amps.

And as Bud has explained to you 50 times now over
many years, that 20,000 amps from a direct stike
has virtually no chance of getting to the
surge protector because with the voltages present
arcing will occur to ground before it ever reaches the surge
protector. Only some of that current will reach the
surge protector. Do you know of any insulator, for
example, in a masthead that can withstand the
voltages of a lightning strike? What are the spacings
of terminals in a service entrance and at what voltage
do they just arc over instead of merrily following the
conductor to the surge surpressor?



*A minimally sized 'whole house' protector starts at
50,000 amps.

Tell that to the companies on your list of surge
protector manufacturers. They make surge protectors
rated at less than that. For example, I recently
installed an Intermatic rated at 20,000. Intermatic
must be a schlock company.


Direct lightning strikes must not even damage a
protector.

Yawn.....


Or a timer switch. *Current in amperes is important for a
protector and for connections to what must absorb that energy. *Single
point earth ground. *Useful answers always discuss where energy
dissipates. *And what is necessary to also protect an electronic timer
switch.

* micky - even bud's citation says what makes any protector effective
AND what is most critical to making a 'whole house' protector useful:

A very important point to keep in mind is that your surge protector
will work by diverting the surges to ground. *The best surge
protection in the world can be useless if grounding is not done
properly.

* Motorola's R-56 Standard says same:

Any ground length over five feet from equipment to ground rod is
almost useless for protection from a close lightning strike. *It is
fine for an electrical safety ground, but too much voltage will be
imposed on the equipment for the equipment to survive from
a close strike.

* Protecting an electronic timer switch means a properly earthed
'whole house' protector. *Protectors, without a short connection to
what absorbs energy, are routinely called "useless".

I'm still waiting for that link to the 50,000 amp surge protector
at HD and Lowes for under $50. Being such an expert on
surge protectors, you should have it at your finger tips.....