Re: House Power Failures and Mac

On Feb 16, 11:05 am, bud-- <remove.budn...@xxxxxxx> wrote:
Francois Martzloff, who was the NIST guru on surges and wrote the NIST
guide, also wrote a technical paper that looks at a *very* strong
100,000A strike to the primary wire on the pole directly behind a house
for a typical urban distribution system. This is a near worst case.
Only 30,000A of the strike flows toward the house on the neutral. The
current on the neutral is directly earthed by the N-G bond in (US)
services. A fraction is coupled to the hot wires. If the strike was
further away, there would be many more paths to earth and the surge
reaching the house would be far smaller.

In his 1994 IEEE paper, Francois Martzloff defines what a plug-in
protector (without that essential connection to earth ground) can do
to household appliances. A conclusion so fundamental that this "NIST
guru" makes it his first conclusion:
Conclusion:
1) Quantitative measurements in the Upside-Down house clearly
show objectionable difference in reference voltages. These occur
even when or perhaps because, surge protective devices are
present at the point of connection of appliances.

Because a protector is adjacent to the appliance, then objectionable
voltages may be applied to that appliance. Bud routinely 'forgets' to
mention that even Martzloff says why plug-in (point of use) protectors
can be ineffective. IEEE paper demonstrated same on Page 42 Figure
8. A fact from Martzloff that Bud must ignore to promote plug-in
protectors. A protector not connected short to earth ground earths a
surge, 8000 volts destructively, through the adjacent TV. Martzloff
also notes the problem. Bud forgets to mention that part.

A higher current rating for a protector means more surge energy is
dissipated harmlessly into earth AND less voltage confronts household
appliances. But only IF a short connection to earth exists. A better
protector is a more conductive path to earth. Protector absorbs less
energy AND shunts (diverts) more energy harmlessly into earth. Bud
'forgets' all this.

A minimally sized 'whole house' protector shunts all 50,000 amps to
earth without damage. Better protectors shunt more. A plug-in
protector never uses all its ratings during surges which means
exponentially decreasing protection. For example, a plug-in 75,000
amps protector will shunt as little as 25,000 amps during the surge.
It assumes the protector only connects to AC lines; not to telephone,
cable, etc. Otherwise that current number becomes even smaller - even
worse protection. Bud 'forgets' these facts to promote grossly
overpriced plug-in protectors - that do not even claim to provide that
protection.

Meanwhile, the UPS would only claim a few thousand amps - is that
near zero protection. Protection decreases exponentially with
dropping current numbers.

The point in both front page Electrical Engineering Times articles
entitled "Protecting Electrical Devices from Lightning Transients":
connection to earth must be short (ie 'less than 10 feet'). Bud posts
a myth about a neutral wire making an earth ground connection. Yes,
for one kind of electricity such as 60 Hz. But that same wire is too
long for surges. Both EE Times articles provide numbers. Same
problem - neutral wire is not sufficient for earthing - is
demonstrated by Page 42 Figure 8. Bud must also 'forget' that fact.
Profits are at risk. Bud's protectors do not have that short earthing
connection and do not even claim to provide effective protection.

If Bud's plug-in protectors earth a surge via a neutral wire, then
a surge is induced on those adjacent wires. More appliances put at
risk. Just another reason why a neutral wire is not an earthing
connection. Just another reason why effective protection earths before
surges can enter the building. Ground wire from the effective 'whole
house' protector is dedicated; separated from all other wires, and
connects directly to single point earth ground. No splices. No sharp
bends. Just more facts that Bud 'forgets'.

Surges must be earthed before entering a building for these and
other reasons. Bud's neutral wire has numerous splices and sharp
bends. So he forgets to mention why that compromises protection.
More engineering facts Bud must 'forget' to promote excessively
profitable and ineffective plug-in protectors.
.

Relevant Pages

  • Re: Band Uisng Tripplite Line Conditioners/surge-suppressor
    ... But put a 100 amp surge on that same Romex wire. ... approaching 12,000 volts, it is not earth ground. ... Therefore voltage increases to dissipate more energy ... Cable TV needs no surge protector. ...
    (alt.guitar.amps)
  • Re: Surge protection without grounded plugs
    ... like 130 ohms impedance to the surge. ... protector attempts to earth a trivial 100 amp surge via neutral wire? ... The effective protector earths before that surge gets anywhere near ... Surge that damaged electronics seeks earth ground. ...
    (sci.electronics.basics)
  • Re: Just had a thought about surge suppressors...
    ... Those "couplesurgestrips" did what no protector must do - failed. ... A surge found earth ground destructively via dishwasher, ... That means a connection from each incoming wire to earth ...
    (alt.home.repair)
  • Re: "chain" surge suppressers?
    ... Required is a low impedance connection to earth - ... Why do plug-in protectors have all but no earth connection? ... Whereas a plug-in protector may be connected less than 0.2 ... AC electricity about wire resistance. ...
    (alt.home.repair)
  • Re: MOVs and surge suppressors
    ... It does not know about 'ground' or 'earth'. ... A surge has energy. ... Therefore protector was at 8000 volts on all wires. ...
    (sci.electronics.basics)