Michell Instruments OptiCal, Руководство пользователя

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OptiCal User’s Manual
8 97079 Issue 9.2, March 2016
INSTALLATION
2.4 Desiccant
The OptiCal has a container fi lled with a desiccant which is used to dry the chamber air.
Figure 7 Desiccant Replacement
The desiccant container can be accessed by following these steps:
1. Remove the clear plastic screw cap on the front panel.
2. Pull out the desiccant container using fi nger tips.
3. Fill with desiccant up to the tapered thread as shown below.
Figure 8 Level of Silica Gel Required
The natural color of the desiccant (dry silica gel) should be orange. As moisture is
absorbed the color will gradually change to transparent.
When the desiccant has become transparent, this is an indication that the instrument’s
ability to generate low humidity is reduced. It is recommended that the silica gel is
replaced or regenerated at this time.
The silica gel can be regenerated by emptying it completely from the desiccant chamber
and drying it in an oven for approximately 3 hours at a temperature between 130°C
(266°F) and 160°C (320°F). After drying it in an oven, allow the silica gel to cool before
re fi lling the desiccant chamber and re fi tting the chamber into the generator. Ensure that
the screw lid is correctly fi tted.
Frequency of desiccant regeneration or replacement is dependant entirely upon the
length of time in operation. Typically, given a normal calibration pro fi le and operation
cycle, the OptiCal can continually generate accurate and stable chamber humidity for a
period of several weeks before regeneration or replacement of the silica gel is necessary.