Advanced Instruments 3900, Руководство пользователя

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4
Calibration
This chapter describes the procedure for calibrating your
instrument. If you have questions or problems regarding the
calibration procedure, please consult Chapter 5 —
Troubleshooting & Service .
Calibration of each required range is accomplished simply by
loading five samples each of the required standards for that
range, in order, in a sample tube cassette, and initiating calibra-
tion as described below.
The calibration standards required are:
Low range: 100 and 1500 mOsm/kg H
2
O
High (optional) range: 1500 and 3000 mOsm/kg H
2
O
Internally, the Model 3900 accomplishes the calibra tion of each
required range in two steps. First, it records the raw means of
the results of freezing point tests on standards at each of the two
calibration levels in the range selected. When five calibration
tests have been acceptably completed at each calibration level,
the instrument will calculate and store the mean of the raw
results of the closest tests. Then, if allowed, it per forms the
necessary conversion calculations, calibrates the output accord-
ingly and reports the change in cal ibration.
Calibration procedure
Place the supervisor/operator keyswitch in the super visor posi-
tion. Select the required range. Two calibration choices are
available, de termined by how calibration is initiated:
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