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Re: Why database is corrupted after re-booting

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  Destructive surges seek earth ground.  Do you think a protector is
going to stop what 3 miles of non-conductive sky could not?  And yet
that is exactly what some protectors manufacturers hope you will
assume.

  Effective protectors don't stop, block, or absorb typically
destructive transients.  Joules does not mean protection is about
absorbing surge energy.   Protectors shunt as even Ben Franklin
demonstrated in 1752.  They shunt as protectors do to protect every
telephone switching station and every commercial radio station.  As was
demonstrated in 1930s GE and Westinghouse papers.  Destructive
transients seek earth ground - either before entering the building
('whole house' protection) or via electronics (surge damage).

  What defines effective protection?  The protector is only as good as
the protection it connects to.  Ineffective protectors hope you never
learn why earth ground is THE one essential component of every
protection system.  Protectors are temporary wires to protection - the
single point earth ground.  Protectors are only effective when they
create a short (typically 'less than 10 foot') connection to earth.

  Series mode protectors (Brickwall, Surgex, Zerosurge) are good
supplemental protection.  But again, without that short connection to
earth ground (the shunt mode protector or hardwire connection), then
even series mode protectors are bypassed or overwhelmed. See that
safety ground wire?  It bypasses the series mode protector.  Meanwhile,
what the series mode protector is doing should already be inside the
electronics.

  Series mode protector will ignore or avoid THE one and essential
component of an effective protection system - single point earth
ground.  Protection is a building wide system.  Its most essential
component is a single point earth ground.  All connections to that
earthing must be short - typically 'less than 10 feet'.  All incoming
utilities must connect to that protection - either via a protector (ie
AC electric, telephone, communication wires) or via a direct hardwire
(ie cable TV, satellite dish).

  Meanwhile, we are only discussing secondary protection.  Primary
protection is provided by the utility:
   http://www.tvtower.com/fpl.html

  To learn about serious protection, maybe start with a benchmark in
this industry - Polyphaser - whose app notes are considered legendary:
  http://www.polyphaser.com/ppc_ptd_home.aspx
What does Polyphaser discuss?  Their products?   No.  Polyphaser app
notes discuss the most critical component on a protection system -
single point earth ground.

  BTW notice a repeated reference to less than 10 feet.  One of many
requirements to reduce wire impedance.  Not resistance - impedance.
That means sharp bends, splices, inside metal conduit, etc all can
diminish effective earthing.

  What do plug-in UPSes avoid discussing?  Earth ground.  No earth
ground means no effective protection.  So they claim protection -
forgetting to mention they don't protect from the typically destructive
transient.  Hoping you will never learn about the most essential
component of a protection system.  That would also explain why
ineffective protectors also have too few joules. They claim protection
- forgetting to mention the protection is not effective.  Protectors
are only as effective as their earth ground.

"Keith C. Perry" wrote:
> Actually, because I lost several thousands of dollars or equipement a couple of
> years ago, I recommended these "brickwall" products to a company.
>
> http://brickwall.com/index.htm
>
> We actually never deployed these units (grounding the communications lines ended
> up being a much cheaper solution) but I did talk and engineer at the company and
> apparently they have some hospitals as client that use unitss.  I'm won't get
> into the technology of how they work since you can read that yourself but I
> remember having a warm and fuzzy after my conversation.
>
> I will pull one quote from their web site though...
>
> "Unlike MOV's, TRANS-ZORBS and similar shunt based surge protectors that use
> elements weighing less than 1/4 ounce, Brick Wall surge protectors can easily
> absorb any surge repeatedly with absolutely no degradation."
>
> The important phrase here is "...absorb any surge repeatedly with absolutely no
> degradation."
> TIP 5: don't forget to increase your free space map settings


---------------------------(end of broadcast)---------------------------
TIP 5: don't forget to increase your free space map settings

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