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3.
Your Dulas Solar Direct Drive Refrigerator.
Congratulations on choosing the Dulas VC88SDD vaccine refrigerator. With over 30 years of
engineering experience in the production of solar powered vaccine refrigerators, Dulas is
considered one of the market leaders in this field.
The VC88SDD is
Dulas’ latest innovation in solar refrigeration. Using our new solar direct drive
technology we have replaced the traditional battery energy store with a ground breaking phase
change solution. With this new technology we can offer the same renown Dulas quality and
reliability that have always kept your vaccines safe, but in a simpler and more efficient package.
How does solar direct drive work?
When the sun shines the solar panels generate electricity which directly drives the refrigerators
compressor, cooling down the refrigerator and its contents. As a result the compressor only
operates during the day. To maintain the temperature at night or when the sun is not shinning the
refrigerator has a phase change lining. This interior lining holds the exact temperatures required
for safe vaccine storage and acts as a
“cold store”, storing energy that keeps the temperatures
stable all day and night.
In order to store sufficient energy to keep vaccines safe for prolonged periods without any
sunshine, the refrigerator must be allowed time to charge
it’s cold store. Under normal
sunlight conditions (8 hours/day of solar irradiance >200W/m²) the refrigerator will take
approximately 7 days to fully charge the cold store and be ready for vaccine storage.
Recommended solar array
The VC88SDD has been designed to meet the World Health
Organisation’s Performance, Quality
& Safety (PQS) standards. The refrigerator has been independently tested to the PQS standard
WHO/PQS/E03/RF05 and is a Hot zone rated appliance with an ambient operating temperature
range of b5C and +43C. For use in such Hot Zone environments it should be powered by
a minimum 400 peak Watt (Wp) solar array with an open circuit voltage (VOC) not exceeding
45Vdc.
