Re: Is Zone Alarm necessary with a DSL firewall?

You are talking about surges. That is lightning. We install surge
protection for a typically destructive surge - lightning. Other surges
made irrelevant by same protection.

How do I know they are equivalent circuits? There is this little
thing called decades of experience. Meanwhile, how do YOU know they
are same? Post those numerical specifications for each unit. Answer
becomes obvious.

How do we know the sub-$100 UPS also is not a line conditioner?
Again, a few decades of experience, the price, and some basic design
experience. However, do YOU know there is no significant line
conditioning? Again, where are those spec numbers?

Your technical knowledge remains insufficient. You have assumed wire
is a perfect conductor. You have assumed there is no difference
between earthing at the electrode and earthing at a wall receptacle.
More numbers. A 50 foot wire connection from wall receptacle may
measure less than 0.2 ohms resistance, but be 130 ohms impedance during
a 100 amp surge. Do the math. That is a 12,000 volt difference which
is why effective surge protector manufacturers want a short connection
to earth with no sharp bends, no splices, earthing wire separate from
non-earthing wires, etc. How does that wall receptacle safety ground
connect to earth without bends, no splices, etc? It does not. With
technical knowledge, one understands why that earthing connection must
meet those electrical parameters. Earthing is surge protection.

A sub-$100 UPS does not provide numerically significant line
conditioning. But again, where are your numbers. Learn from numbers
and basic electrical principles why that earthing connection must be
short. How many joules on that sub-$100 UPS? Where are your numbers
- which must be provided to believe subjective claims? How do you know
anything you have assumed if you don't have these numbers?

You said:
Many people don't realize that a quality UPS, ... will protect as a surge
protector as well as act as a line 'conditioner'. You know, like the $150
Monster surge protector/conditioners ...

Right in your early statement - that is you talking about lightning
protection. Back then you discussed 'quality UPS'. Why now are you
discussing a sub-$100 UPS? Apparently you are confused as to what is
'quality' and what are typically destructive surges. But again, where
are your numbers so this confusion can be rectified? Why do you not
post numerical specifications from those manufacturers? If you knew
your statements to be true, then you also have those numbers.

DanS wrote:
OK. How do YOU know they are the same ? Have you see schematics ? Have you
done independant testing ? YOU prove to ME that they are the same.

What is this typically destructive transient you speak of ? If you are
speaking of lightning, I never claimed anything about lightning protection.
You asked me for specs and I posted specs for you for an APC model.

I NEVER SAID lightning protection....my OP was exactly.. 'They will protect
as a surge protector as well as act as a line 'conditioner'.' (With line
conditioner meaning filtering of the AC.)

Nor did I ever say anything about RECOMMENDING ANYTHING over a whole house
solution. YOU are the one making the connection between the two.

While it's more than 10 feet from the panel, these devices are earth-
grounded as well through the house wiring. If you examine inside you
breaker box, you will probably see that all of the AC lines 'ground' wire
AND neutrals go back to the ground bar inside, which is tied to earth
ground thru the grounding rod outside the home at the point of power entry.
So indeed, MOV/GDT protected devices do discharge to earth ground when
necessary, that is, if your home does have 3 wire AC.

AND AGAIN, NOT SPECIFICALLY TALKING ABOUT LIGHTNING.

.

Relevant Pages

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