On Apr 2, 11:31 am, "Joseph Meehan"
wrote:
w_tom wrote:
You have not grasped the various type of transients,
If you car to post a single valid link to a non-commercial
authoritative site that supports and explains your views, I will be happy to
view it and comment on it.
--
Joseph Meehan
Dia 's Muire duit
My favorite part to Tom's usual rant above is this:
"What happens when a
surge comes down any or all black, white, and green wires; and leaves
via phone wire, wooden table, linoleum floor tile, or any other
conductive material? Latter is the surge that does damage. When it
leaves, where does it go? Earth ground. "
In the above, he acknowledges that a surge can come in via the power
line
and then exit via everything from a phone wire to a wood table. Yet
he refuses to
acknowledge that it could also leave via a point of use surge
protector shunting
the surge to ground. And it would seem that would be a much lower
impedance
path than a wood table.
Where Tom goes astray is he starts with good advice, which is that
surge protection
on the AC panel with a good ground is the most effective and good
practice. But then
he quickly decends into nonsense, when he claims that point of use
protectors offer no
protection at all and are actually destructive. Another of his
rants that I like is that all appliances have
surge protection already built into them. Hmmm, let me think....
What would I
rather have get blown due to a surge? The MOV in a $20 plug in
protector
or the MOV in a $2000 HDTV?
Here's some of what UL has to say about surge protectors. They
specifically talk about
the point of use type, say they rate them and don't say they are
ineffective.
http://www.ul.com/consumers/surge.html
You're at your home computer when suddenly the lights flicker. Your
computer screen fades to black; then copy is restored. Sound familiar?
You've just experienced a power surge. Power surges -- also known as
transient voltage surges-- are brief spikes of power that can travel
through power lines. Power surges can permanently damage computers,
televisions, fax machines and other home appliances that contain
microprocessors and sensitive electronic components.
Many people assume that surge suppressors can protect their home from
lightning damage. Surge suppressors are not lightning protection
devices - they cannot protect your home or your home's internal
electrical wiring from a direct strike. Surge suppressors can,
however, protect your equipment from voltage surges caused by
unexpected occurrences such as a utility pole downed by a storm.
Surges can also generate from inside the home. For instance,
appliances such as furnaces, air conditioners and vacuum cleaners can
cause power surges in your home's electrical system when turned on or
off. And in some cases, remote lightning strikes cans cause surges.
However, UL Listed transient voltage surge suppressors (TVSS) can
reduce the risk of such damage.
The unpredictable nature of surges makes it difficult to suppress
them; you never know when, how long or how powerful they will be. In
some cases, a surge may have a higher energy level than the device can
handle. When this happens, the surge suppressor may be damaged and
lose its ability to provide protection against future surges.
Some surge suppressors look very similar to multiple-outlet power
strips but obviously have additional features to suppress surges.
Other surge suppressors resemble common plug-in adapters. Not all
power strips and adapters offer surge suppression, so make sure the
product and product packaging clearly states "UL Listed Transient
Voltage Surge Suppressor."
UL evaluates surge suppressors for fire, electric shock and personal
injury hazards, and also measures and categorizes the devices for how
much voltage they can "clamp," thus preventing excess voltage from
passing through to electronic equipment. UL refers to this as a
"suppressed voltage rating," with ranges from 330V (volts) to 4000V.
Believe it or not, the lower the rating, the better the protection.
Whatever surge suppression protection you're looking for, make