Labconco Rapid Digestors 23080 - Manual (Page 5)

INTRODUCTION
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The exposed surfaces of the unit are made of aluminum finished by a chemically etched
process to withstand corrosion. The light(s) located on the front of the digestor indicates
when the digestor has reached set-point temperature and any malfunction that could
occur, along with providing over and under temperature set-point indications. Flashing
of the light(s) indicates proper temperature control.
Control Unit
The solid state proportional controller regulates the temperature of the digestor unit. The
Rapid Digestor-25 control unit is factory set to accept 208/240 volts, 50/60 Hz requiring
20 amp fusing and the 4-Place set to accept 115 volts, 50/60 Hz requiring 15 amp fusing.
Temperatures from a few degrees above ambient to 450° C can be set on the set point
indicator dial. Each controller is factory calibrated for proper temperature setting before
leaving the factory and should not require re-calibration. A calibration resister is
provided for a calibration check of the set-point temperature if required. (Refer to
Maintenance Section of manual for procedure). A red indicator light on the front panel of
the control unit is illuminated when unit is energized. Flashing of the light(s) located on
the digestor unit indicates the set-point temperature, when it has been reached, the
temperature of the digestor is proportionately controlled by the controller.
Digestion Tubes, Flask Rack, and Retainer Plate
Digestor Model 23006 is supplied with one set of thick-walled, heavy rimmed, heat
resistant glass digestion tubes with volumetric calibration marks at 250-ml volume.
Digestor Model 23000 is supplied with tubes having the same features as with Model
23006 except without calibration markings. Models 23012 and 23080 are supplied with-
out digestion tubes. The heavy rims allow the tubes to hang in the stand when the rack is
lifted. The flask rack is constructed of aluminum alloy and holds the tubes during diges-
tion as well as during cooling, dilution, washing, drying, and weighing of samples.
Samples are weighed or volumetrically delivered into the tubes and the digestion mixture
added. The tubes in the rack are then lowered into the digestor unit. The samples are
digested at the proper temperature for a predetermined amount of time. Digestion
temperature and time is determined by the type of sample being digested. After
digestion is complete, the flask rack containing digested samples must be removed from
digestor, cooled and diluted with water. The digestion is now complete and ready for
appropriate determination. The retainer plate (Rapid Digestor 25-Place only) is attached
to the digestor flask rack to lock the tubes in place, allowing the tubes to be emptied,
washed, and dried as a unit, without removal from the rack. The retainer plate is not to
be used during digestion, cooling or dilution of the samples.
CAUTION: The top surface of the digestor is hot during operation and for a period of
time after shutdown. To avoid the possibility of burns, do not touch the surface with bare
hands.