On Apr 2, 10:53 pm, "w_tom" wrote:

Martzloff in an
IEEE paper - also warns of same damage "even when or perhaps because,
surge protective devices are present at the point of connection of
appliances. "
Martzloff said in the same paper "Mitigation of the threat can take
many forms. One solution. illustrated in this paper, is the insertion
of a properly designed surge reference equalizer [mulitport
suppressor]." Martzloff consistently says plug-in surge suppressors
are effective, as he did in the NIST guide.


Joseph Meehan - repeatedly posted were links to non-commercial
authoritative sites such as Martzloff and IEEE. Later you ask for non-
commercial citations. Why do you keep asking that question after
information is provided? Why the standard denials?
Because you have NEVER posted a link to a site that says plug-in
suppressors are NOT effective. Nor have your quotes from sources ever
said plug-in suppressors are not effective. Many of your quotes are
from sources that, in fact, said plug-in suppressors are effective,
like the IEEE guide, and Martzloff above.


trader cannot grasp this concept: wire impedance. trader - why is
the protector in Figure 8 at 2000 and 8000 volts? Why ignore
excessive wire impedance even in this 'mike holt' provided figure?
But again I say to you - learn about wire impedance. Look at figure
8: why a TV is at 8000 volts. Wire to earth ground is too long, too
many sharp bends, splices, etc. Too much impedance means ineffective
earthing. So where does that 8000 volts find earth ground?
Destructively via an adjacent TV. The non-commercial page 42 Figure 8
again demonstrates Martzloff's problem with plug-in protectors - that
can even contribute to appliance damage.
A readers guide to w_'s rant:
w_ refers to the IEEE guide, not 'mike holt'. The figure shows a surge
on a CATV source with 2 TVs connected. TV1 is protected by a plug-in
surge suppressor. 2000V does not appear at the TVs. The plug-in
suppressor at TV1 did NOT contribute to damage, but reduced the
voltage at TV2 from 10,000V to 8,000V. But the point of the figure is
"to protect TV2, a second multiport protector located at TV2 is
required". The IEEE says the earthing path for the surge is not
through the TVs or branch circuit. "The vast majority of the incoming
lightning surge current flows through" the earthing wire from the CATV
ground block to the power service. This figure part of the IEEE guide
explanation of how plug-in suppressors work. But the explanation
violates w_'s religious beliefs in earthing.

Other points the IEEE makes he
"If the CATV, satellite, or phone cables do not enter the building
near the service entrance, the only effective way of protecting the
equipment is to use a multiport protector." It is common to have entry
points for phone, CATV or satellite to be distant from the power
service. That prevents establishing a "single point ground".

Since CATV entry ground blocks do not limit the voltage from core
conductor to shield, that voltage, according to the IEEE guide, is
only limited to the breakdown voltage of F connectors, typically
2000-4000V.
"There is obviously the possibility of damage to TV tuners and cable
modems from the very high voltages that can be developed, especially
from nearby lightning."
CATV wires going through a plug-in suppressor will have that voltage
limited.


Meanwhile a surge arrives at an HDTV and surge protector. The
protector is so grossly undersized as to disconnect as fast as
possible - to smoke. HDTV is then left to fend for itself. No
problem. HDTV has sufficient internal protection. But the naïve
proclaim "a surge protector sacrificed itself to protect my TV".
Wrong. A surge too small to harm an HDTV struck both TV and surge
protector simultaneously. Only the surge protector was grossly
undersized - vaporized - so that the naïve will promote more sales.
Only the naive would buy a surge suppressor that is grossly
undersized. Suppressors with very high ratings are readily available.

Only the naive would post an argument requiring a grossly undersized
suppressor.

Only the naive would think a HDTV could handle any surge that hits it.


Protectors without that short ('less than 10 foot') connection to a
single point earth ground cannot provide protection. A protector is
only a connecting device to earth ground. That 'magic box' does not
stop what 3 miles of sky could not.
The religious belief in earthing. As explained by the IEEE guide, plug
in suppressors work primarily by CLAMPING the voltage on all wires to
the common ground at the surge suppressor, not earthing or stopping.


So may words, so little that is minimal relevant to plug-in
suppressors.

The IEEE and NIST guides both say plug-in suppressors are effective.

And w_ still can't find a link that says plug-in suppressors are NOT
effective.

--
bud--