Buchi DuMaster D-480, Руководство по эксплуатации

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Operating instructions DuMaster D-480 ©BÜCHI Labortechnik AG
7 - Using the instrument 139
Conditioning samples
Conditioning samples are measured with standard substances at the start of every series of analyses.
They are used to check...

... the correct run of the analysis.

... the proper condition of the instrument.

... flow and pressure behavior of the gases.
Daily factor determinations
Determination of the daily factor serves...

... to fine-tune instrument calibration to room conditions at the time of analysis.

... to assess the condition of the instrument by observing daily factor fluctuations and drift trends.
When to perform routine measuring work
Perform routine measuring work...

... at least once a day.

... additionally when measuring breaks last longer than 2 hours.
If a series of analyses exceeds a duration of 5-6 hours (carousel completely loaded), it is advisable to
determine the daily factor additionally at the end of the series.
Performing routine measuring work
Proceed as follows:

If desired, perform a blank value determination. For details, see Types of blank value
determination and their settings.

Measure the conditioning sample twice. Use a standard as run-in sample which corresponds
your sample matrix:

250 mg aspartic acid with method "250mgStandard".

Measure the following daily factor sample three times and compute the daily factor:

250 mg aspartic acid with method "250mgStandard".

Measure a maximum of 50 real samples.

At the end of the series, measure the following daily factor sample four times and check the daily
factor:

250 mg aspartic acid with method "250mgStandard".
Checklist for blank value / conditioning and daily factor measurements
Purpose
The checklist helps you to check whether the instrument is ready to measure blank value,
conditioning and daily factor samples.
Checklist
Go through the following list:

Are the operating gases on?

Are the furnaces at setpoint temperature?

Is pressure OK?

Display on the PC "Press. Input": 1300 - 1350 mbar