Assumed was that phone line appliances are damaged by a
wave, entering on phone line, then crashing onto that
appliance like it was a beach. Oceans waves and electrical
transients are completely different. First an electrical
transient current flow through everything in a complete path
from cloud to ground. Then item or items in that path are
damaged. Essential incoming and outgoing paths are required
to have damage.
As demonstrated in the previous post, what is a most common
source of damage to phone line appliances? AC electric.
Why? Phone line provides the good outgoing path to earth.
Highest wires on utility pole provide a best incoming path. A
complete circuit - incoming and outgoing paths - exist for
damage to occur. Myths instead claim a modem is damaged when
only an incoming path - phone line - exists.
Meanwhile, a protector damaged by a transient provides
ineffective protection. Even modems have internal
protection. Sometimes a transient too small to overwhelm
protection inside a modem with damage the grossly undersized
and adjacent protector. Undersized so that you will *assume*
the protector provided protection.
Of course, even an effective 'whole house' phone line
protector provided by the telco will only be as effective as
the earth ground YOU have provided. A protector is only as
effective as its earth ground, which plug-in protectors hope
you never learn. Profits on grossly undersized plug-in
protectors are too large to be honest; to discuss the most
critical component in any protections system. Earth ground.
No dedicated connection to earth ground on that protector
meant no effective protection.
Also demonstrated in a figure from the National Institute of
Standards and Technology is how improperly earthing can
destroy telephone appliances. In this case, a fax machine is
damaged when telco and AC electric earthing is not properly
installed:
http://www.epri-peac.com/tutorials/sol01tut.html
But again, what do industry professional always discuss?
Earthing. Earthing is the most essential part of a protection
'system'. Something that ineffective plug-in protectors
routinely avoid discussing.