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INTRODUCTION
1.1.
USE AND FUNCTION
DF series Ultra Low Temperature Freezer is designed for the storage of the samples needed to
store at ultra-low temperature and it is used in the hospitals, blood banks, epidemic diseases
research centers, research laboratories in the universities, genetic engineering and bio-
pharmaceutical industry.
DF Series Ultra Low Temperature Freezers are capable of cooling down to set points between -
45°C and -90°C with 1°C sensitivity and keep temperature stable within given tolerances. The
live of the most of the biological samples stop at -70°C. These samples can be stored for a long
time without loss of their vital functions by using Ultra-low temperature freezers. DF series
protect living cells and tissues for a long time without any destruction.
The refrigerant gas passes through evaporators placed under each shelf, bottom of the chamber
and top of the chamber; thus, each compartment of freezer is cooled directly. DF series
provides a stronger and more rapid cooling with its
DirectFREEZE™
technology. Refrigeration
system is cascade system in DF series. The refrigeration is provided by non-explosive refrigerant
gas which does not include CFC.
The power switch is equipped with a key lock to prevent unauthorized usage. Door handle on DF
series can be opened easily. Moreover, silicon gasket placed on the door protects air leakage.
DF series Ultra-Low Temperature Freezer has audible and visual alarm systems for the following
cases; high and low temperature conditions, power failure, temperature sensor failure and
other faults related with the microprocessor control system. DF series store last 50 failures in
the memory and these errors can be followed on the display. Standard Ethernet connection
feature enables email sending to five different e-mail addresses in case of any error. DF series
offer
AlerText™
GSM module as an option and SMS can be sent to five different mobile phone
numbers in case of error.
The display is fed by an automatically re-chargeable battery in case of power failure. Therefore,
temperature in the chamber is displayed in case of electricity interruption. Remote alarm outlet
and the outlet for connection to central alarm system are offered as standard.
DF series ultra-low temperature freezers have internal memory which can store temperature
values for 10 years. In addition to internal memory, temperature values can be recorded in USB
stick. DF series have a weekly circular chart recorder as an option. The temperature in the
chamber is recorded by this chart recorder operated by the backup battery. Chart recorder is
equipped with a key lock to prevent unauthorized usage.
CO
2
back-up system is an optional accessory. This system provides to keep temperature stable
at -60°C in case of power failure or compressor failure. Thus, samples in the chamber are
protected against temperature increase.
