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Excellent information on surges and surge protection is in a guide from
the IEEE at:
And a less technical guide from the US NIST at:
Francois Martzloff was the NIST guru on surges, wrote the NIST guide,
and has may published technical papers on surge protection. One of them
looks at the energy that can reach a plug-in suppressor on a branch
circuit with surges coming in on a power line of up to 10,000A (the
maximum that has any reasonable probability of occurring). The maximum
energy dissipated in the plug-in suppressor was 35 Joules. In 13 of 15
cases it was 1 Joule or less. There are a couple major reasons the
energy is so small.
Neither service panel or plug-in suppressors protect by absorbing
energy. Both absorb some energy in the process of protecting.
Plug-in suppressors do not work by "stopping" either.
Service panel suppressors are a real good idea.
But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."
Service panel suppressors do not prevent high voltages from developing
between power and signal wires. The NIST guide, citing US insurance
information, suggests most equipment damage is from high voltage between
power and phone/cable wires.
All of these "responsible" manufacturers also make plug-in suppressors
except SquareD. For it's "best" service panel suppressor SquareD says
"electronic equipment may need additional protection by installing
plug-in [surge suppressors] at the point of use."
w_ has a religious belief (immune from challenge) that surge protection
must directly use earthing. Thus in his view plug-in suppressors (which
are not well earthed) can not possibly work. The IEEE guide explains
plug-in suppressors work by clamping (limiting) the voltage on all wires
(signal and power) to the common ground at the suppressor. Plug-in
suppressors do not work primarily by earthing (or stopping or
absorbing). The guide explains earthing occurs elsewhere. (Read the
guide starting pdf page 40).
Being evangelical in his religious belief in earthing w trolls
google-groups for "surge" to spread his dogma. nixtechno said the magic
Note that all interconnected equipment needs to be connected to the same
plug-in suppressor, or interconnecting wires need to go through the
suppressor. External connections, like phone, also need to go through
the suppressor. Connecting all wiring through the suppressor prevents
damaging voltages between power and signal wires.
Because UPSs, like plug-in suppressors do not protect primarily by
UPSs of the type commonly used do not *intrinsically* provide surge
protection. (Full time conversion UPSs do.) The same type of protection
as in plug-in suppressors is commonly included in UPSs. High ratings are
easier to find in plug-in suppressors.
For real science read the IEEE and NIST guides. Both say plug-in
suppressors are effective.
Compare that to w's sources that say plug-in suppressors do NOT work.
There are none.