Advanced Instruments 3900, User Manual

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displayed and the instrument will await operator re sponse. Switch to
supervisor to continue or press STOP to cancel recalibration.
• If the sample probe is replaced, the sample probe bin number must
be determined and set be fore the Model 3900 can be calibrated.
After the sample probe bin number is set, the CALIB calibration
proce dure (choice 1) must be used; choice 2 will generally produce a
“ Calibrator out of Range ” error message.
• The Model 3900 can detect certain gross calibration errors such as
reversal of the standards, but it remains the responsibility of the
operator to be sure to introduce accurate standards of the specified
values.
• The ambient air may contaminate or evapo rate samples in the cas-
sette if allowed to re main for any appreciable time before testing.
• In an extremely dry room, high range NaCl osmometer standards
will evaporate and increase in osmolality very rapidly. For reliable
calibration under these condi tions, it may be necessary to pipet no
more than one or two samples at a time and place the freshly pipet-
ted samples in the calibration cassette just in time to be tested.
• Good laboratory techniques, as recommended in Chapter 2, are as
important during calibration as during normal opera tion. If the cali-
bration test results are not acceptably repeated throughout the five
tests at each calibration level, the instrument will report
“ Calibration out of Range ”, and the entire calibration procedure
must be redone. If the repeatability problem recurs despite good
operating technique, please call or write immediately for Hot-Line®
service.
• Pressing STOP at any time during calibra tion will completely cancel
the current recalibration; the previous calibration will be retained.
Calibration