|
Answering
the question regarding the life of a FLATLITE electroluminescent
panel, or for any electroluminescent based product, is
a somewhat involved answer.
EL does
not fail to light so it technically has NO end of life,
rather it is the decaying luminance level (brightness)
in a particular application that determines when it is
no longer useful.
The
decaying luminance is exponential - meaning more rapidly
early and extremely slow later in time, which is also greatly
affected by how the phosphors are powered (this means the
inverters output wave shape, voltage and frequency) and
by the ambient temperature the panels are being run in
(cold temperatures yield better results than warmer temperatures).
All EL
technologies share the same characteristics with the major
variation being the quality of the base phosphor material
with the secondary factor being the way the panel is manufactured.
The phosphors
available from each manufacturer are graded according to
their specific life and brightness characteristics. If the
same exact grade is being used by two manufacturers, their
methods of making or driving the panel may produce results
that differ as much as 25%. This is why the decision to use
EL technology for an application should be independent of
what a particular supplier may quote for "life".
Comparing
two EL technologies must be done with all the factors (power,
temperature, phosphor grade) equal, which may not be possible
given the data normally available from the different manufacturers.
Our Flatlite
inverters employ an active compensation scheme, so more
voltage is fed to the panel as it ages early in its life.
This compensation scheme, combined with variable starting
brightness levels, greatly varies the useful life of a
product. In one test, for example, samples were run at
25, 50, 75 and 100% starting voltage. After 2 years of
running 24/7, the panel started at the 25% level was the
brightest of the 4 samples and the other 3 were virtually
the same.
In Signage
applications where the brightness required is high but
the “on time”
(duty cycle) is only the night time hours as in a bus or
taxi sign, the Useful life is approximately 12 –18 months.
In Aisle
Lighting applications like Movie Theaters, both the brightness
is low and the duty cycle is low resulting in a Useful
life of 5 years or more.
In outdoor
Architectural Lighting applications, the required brightness
is relatively low but the duty cycle is about 50%. The
Useful Life of this type application can be 3 – 5
years. EL panels do not “burnout”, in time they
will become dim enough to require replacement.
NOTE: panels
with an Exterior Grade Laminate are available for an additional
charge, if you are unable to protect your panel from UV
and moisture, request
a quote.
|
