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| On Mar 14, 7:13 pm, phil-news-nos...@ipal.net wrote:
> In the case of the protector being attached to something other than the
> power branch circuit, that certainly can shift the surge from the other
> wiring (antenna lead, cable TV, telephone, etc) to the power wiring, and
> on into other appliances near there on the same circuit. It can also
> put the surge back on the panel, but if it is the main panel, at least
> it has a better path to ground there. As part of an overall good design
> strategy for surge protection, point of use protectors do help reduce
> the risk of damage from a surge. But in cases where the whole system is
> not properly designed, then these protectors (and even some other things
> otherwise intended to protect) can actually cause more harm. The key is
> to design the whole system right. Then these protectors can supplement
> that protection for the few things a whole house system cannot catch.
Problems with point of use protectors: First, if the major surge is
not earthed before entering a building, then the plug-in protector can
contribute to appliance damage - make that damage easier. Unlike Bud,
I designed things. In one stunningly educational location, two plug-
in protectors earthed a lightning strike through two adjacent
computers, through the network, and out to earth ground via a third
computer. Had plug-in protectors not been there, then all three
powered off computers would not suffer damage. Surge permitted in the
building and on the black wire was shunted (clamped, diverted,
connected) to green safety ground wires by a plug-in protector. Surge
was connected to earth ground, destructively through computers, by the
protector. We literally traced the surge circuit and replaced all
parts in that circuit to earth ground. All computers were restored to
normal operation. The plug-in protector earthed surges through
adjacent computers because the protector was too close to electronics
and because the necessary 'whole house' protection was not earthing.
Without the 'whole house' solution, plug-in protectors can do more
damage. Bud says plug-in protectors alone are sufficient protection.
Second, all appliances contain internal protection. The plug-in
protector does provide protection from some types of transients. But
most all those transients are made irrelevant by protection already
inside all appliances. Protection that can be subverted (bypassed) as
demonstrated in point one.
Third, the plug-in protector can make appliance damage easier when a
'whole house' protector and earthing are not installed. But then the
problem gets worse. For example another result is 'scary pictures'.
'Scary pictures' are just another problem with plug-in protectors that
are often grossly undersized (to maximize profits) and located where
fire danger is highest. 'Scary pictures' are another reason why a
properly earthed 'whole house' protector is still required.
Fourth, for all that money spent on plug-in protectors, better is to
spend that money upgrading the earthing system. Many if not most
homes do not have sufficient earthing. Earthing must both meet and
exceed post 1990 National Electrical Code requirements no matter what
protector is used. Unfortunately something like one in ten of the
oldest homes have been observed missing any earth ground. Money is
better spent on what provides protection rather than spending $25 for
a $3 power strip containing some ten cent parts - to supplement what
is not yet installed. Plug-in protectors are not the complete
protection solution that Bud claims. They are only supplemental to a
'whole house' solution - and cost how much?
Fifth, a power strip protector is for one type of surge. How
frequent or destructive are these differential mode transients? Well
how often is the homeowner replacing GFCIs and dimmer switches?
Extremely rare. We spend tens or maybe 100 times more money on
protectors for a type of surge that rarely causes damage? Meanwhile
one 'whole house' protector so reduces this type of surge as to
convert an 'almost never damaged' dimmer switch into 'never damaged'.
Just another reason why money is better spent where protection is so
much more effective.
Yes, the plug-in protector can do something. But those 'somethings'
are made so irrelevant by installing and earthing the effective
solution. But the effective solution is necessary if or if not using
plug-in protectors. Best money buys a 'whole house' protector for all
types of surges. Most important, upgrades earth ground that is too
often insufficient for any protection and missing in the oldest
homes. Bud says earthing is not necessary - that 'clamping to
nothing' is sufficient protection. Bud denies a 'whole house'
protector is necessary when using plug-in protectors. Bud denies
because Bud promotes obscenely profitable plug-in protectors.
Why do major facilities (ie telco COs) not install plug-in
protectors? Yes, a plug-in protector has some purpose. But less
money for better protection is spent on the earthing system and on one
protector for all types of surges ('whole house' type). Even plug-in
protectors require proper earthing and a 'whole house' protector - in
direct contradiction to what Bud claims.
Best solution has always been to earth a typically destructive surge
before it can enter the building. Same soltuion makes irrelevant
those other and lesser transients. Same solution is also necessary if
using plug-in protectors.
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