1. At the direct stroke of lightning, electric
current is typically 30 kA (M.A. Umann
recorded
currents up to 200 kA). A single direct
strike
can damage or destroy Gas Tube Element
and/or
body of a protector, regardless of
its current
rating. The energy discharge is triggered
when voltage increases to the rated
voltage
of the gas tube element. Consequently,
almost
the entire remaining energy shall be
dissipated
at once. The timing of discharge is
normally
some hundreds nanoseconds to microseconds
to trigger level, and some hundred
microseconds
to milliseconds for remaining energy.
2. Effects of lightning by induced electromagnetic
fields vary widely in energy. Induced
damage
ranges from similar effect as direct
stroke
for large energy, to no damage from
small
induction. The life of a Gas Tube Element
is eventually consumed by small energy
surge
events.
3. Almost all types of large current types of
Gas Tube Element are ceramic sealed
and cannot
be visually checked. The gas tube element
is activating even on small energy
surges.
Each surge reduces the life. You never
able
to judge by your eye how much life
your gas
tube has left in case of Ceramic sealed
type.
The life is normally 400~600 times
under
test condition of 8 micro sec. / 20
micro
sec. per industry standards. Ask your
vendors
to recommend how to check life of their
surge
protectors in field.
4. The lightning in the natural electro magnetic
environment averages as much as several
hundred
surges per day including large and
small
that has reported officially. Manually
monitoring
it 24/7 is impossible. If a Gas Tube
Element
fails when you are not aware of it,
you will
be under Non-Protected situation even
you
have scheduled element changes.
5. RF TEC Mfg., Inc. uses specially made Gas Tube Elements with
Glass Body for 5 kA current rating.
This
reduces Non-Protected situations. Looking
inside Gas Tube through the Glass Body
will
let you see the actual condition of
Gas Tube
Element. The inside glass darkens with
use;
a black color indicates time for replacement.
The glass eventually blackens in case
of
small induced surges, but goes entirely
black
at once from a direct strike as pictures
on the our web site show. There is
not available
large electric current type with glass
body
gas tube element that can be visually
checked.
The result is almost the same with
large
electric current ceramic type, since
the
energy of direct and large inductive
strikes
exceed the rating of even the largest
electric
current type elements.
  
(From left to right: Original, Damaged
1,
Damaged 2)
6. Some of our valuable customers kindly reported
us what happened after stroke. Before
using
our In-Line Surge Protectors, their
coaxial
antenna cables were split and the radios
were damaged. However, all those were
saved
when the next direct strike hit, after
installation
of our protectors. The gas tube element
was
destroyed, but the body is still good
and
the surge protector reused by simply
replacing
the gas tube element, easily installed
in
the field by the customer.
7. Stocking new surge protectors for replacement
requires high investment, but replacing
only
gas tube elements is very economical.
8. There are tradeoffs for both large electric
current type in Ceramic Sealed types
and
our Glass Tube types. We have confidence
based on reports from the field that
our
Surge Protectors are generally the
best solution
for protecting your radio equipment
and coaxial
antenna cables.
9. Ceramic sealed gas tube elments are available
in 10KA, 20KA, 30KA and 40KA current
ratings.
High rated types withstand high energy
and
are effective mostly for inductive
lightnings
and EMP. Although longer life, the
life is
still limited. The life is also 200~600
times
under standard test condition of 8/20
micro
sec. per IEEE. Actual energy of lightning
vary case by case, affecting life time.
You
never know it. Problem is that once
large
energy like direct strike or equivalent
inductive
lightning had come, "the life
is over."
Since then, you will be exposed and
unprotected.
Your surge protector has changed to
just
connector adapter, and you have no
protection.
You need to know whether your gas tube
element
inside protector is still effective.
We are
using special semi-transparent Glass
sealed
type that is rated 5KA. However, we have tested Lightning Impulse
Cycle Test/Destroy Test at 10KA/500KV
at
Public Government Test Lab and passed
80
times. Higher than 10KA damage Connector in case
of N-type even your N-type Plug and
Cable
Assemblies due to the structure of
the connector.
May be withstand one time for a lightning
strike. We have confirmed damage even
N-type
Surge Protectors and Cable Assemblies
of
famous competitors during test. Higher
than
10KA is NO Meaning.
Our design lets you see if your protector
is still a protector or is dead. The body
of the gas tube element changes body color
occasionally into black by level of the energy.
Center or entire gas tube completely in black
color is time for replace. You can change
gas tube inside by yourself. You need to
know this matter. It is up to your decision
that
ALWAYS STAY PROTECTED !
RF TEC Mfg., Inc.
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