On Thursday, February 13, 2014 6:48:19 AM UTC-5, Bob_Villa wrote:
Okay, okay...this will be my last two-cents on this...you can show me all kinds of specs and recommendations, and say how "in theory" these work

It's not "theory". Surge protection has been well researched, modeled and
actually deployed and used in the real world for most of the last century.
It's critically important to many major industries to understand the
nature of surges, what they typically look like and how to protect
billions of dollars worth of equipment from them. Studies have been done
to find out what the typical destructive surges look like. We even have
ANSI and UL testing standards to make sure that surge protectors do
what they are supposed to do.
The IEEE panel that wrote their guide is made of up electrical engineers
with decades of experience in surge protection in the real world.


(and they will work in a very specific and narrow window of lightning surge). But the "real world" data is not there...it is anecdotal at best because every situation is different.


We have NIST, IEEE who say surge protection is possible and it
works. We also have folks at major facilities like the Telcos, cable
companies, computer facilities, etc that say you're wrong. If
surge protection was not possible, the telcos for example, with
hundreds of miles of exposed wire, would have blown up central
offices after lightning storms. That fact alone should tell you
that surge protection works. And like the IEEE recommends, they use
a tiered strategy, with the main protection being where the cables
enter the building, backed up by addional protection on the actual
line cards on the switch. That makes sense, you want to stop the
surge before it even enters the building or right at that point.
Any remaining surge is handled by smaller surge protectors at
the eqpt.

Yes, situations can be different, but the industry agrees on
the methods to protect, with the exception I guess of the one
guy you found. And whole house surge protectors don't only work in
a very specific and narrow range of lightning surge. One rated
at 20KA per line or more will cover probably 99% of surges
that a house could see. As Bud pointed out:

" As I have often posted, an investigation by the surge expert at the NIST
looked at the current that could come in on service wires. He used a
100,000A lightning strike (only 5% are stronger) and the strike was to a
utility pole in the alley behind the house with typical overhead
distribution - extremely close. This is, for practical purposes, a worst
case. The surge current to the house was 10,000A per service wire.
Service panel protectors with far higher ratings are readily available. "



So you either believe...or you don't! Sort of like the "wind chill" and frozen pipes thing! *L*

The problem is that you're inconsistent. For some reason you
believe plug-in surge protectors work and you use them. Yet you claim
that whole house ones, which are also based on MOVs are useless.
And the only cite you have for that
is the guy who owns a company making a totally different type of
surge protector and he says both the whole house and plug-ins are
useless, you should buy his. That doesn't do much to support your case.
He also cites a coffee pot turning on and off as an example of
a surge that we should apparently be concerned about. Really?
If a coffee pot is the type of surge to worry about, then what
about a 40A, 240V oven? Those should be blowing up stuff all
the time that isn't protected with a plug-in, but that sure
doesn't seem to be happening in my world. The oven isn't killing
the dishwasher, fridge, microwave, etc.

His case against whole house surge protectors apparently centers
on the fact that whole house ones typically have higher clamping
voltages, eg 700V as compared to say 400V for the plug-in ones.
From that he claims that the plug-in will take most or all of the
surge and from what I see, the only reference he has is a study
on TOV (temporary overvoltage) which is *not* a surge. That doesn't
make sense to me, because a lightning strike on a utility wire
near the house is going to present such a large surge, that the
voltage is going to exceed 700V at the panel. So, I see no
electical principle whereby that MOV would not turn on, limiting
the surge right there. Further, the plug-in one is also
separated by whatever impedance the wiring has between it and
the panel, so it's hard to believe that most of the surge is going
to bypass the panel one and go to the plug-in. And that's what you
want, not the powerful surge going into the house and then rely solely
on plug-ins, to try to deal with the surge. And what about the ovens, dishwasher, furnace, etc?