Thermo Scientific APEX 100, Руководство пользователя

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Thermo Scientific APEX User’s Guide
Page 113
Detect Level
The detect-level function is part of the Main Menu, as shown below. (Your screen will
look different if IXR is enabled.)
Detect Level
Overview of the Detect-Level Function
The detect level can be set in two ways: using the detector’s auto-calibration function or
by keying in a value. During the auto-calibration procedure, the detector first monitors
the background noise level and assigns it a value, say 15. Then, after you have passed a
test sample of contaminated product three times through the search head, the detector
sets the minimum detect level to 2–3 times the background level. In our example, the
detector has assigned a value of 40 to the detect level. As a result, any product that
gives a reading in excess of 40—the detect level—will be rejected.
In summary, by keying in values for the detect level, you can fine-tune which products
are rejected. For example, if the contaminant signal is strong and the background noise
varies widely during the working day in your particular operating environment, you may
see a number of false rejects. You could remedy this situation by keying in a larger
value for the detect level (for example, 100).
Setting the Detect Level
The detect level can be set using the detector’s auto-calibration function or by keying in
a value.
• If you want the auto-calibration function to set the detect level, see page 55
(conveyor), page 73 (gravity-feed), page 90 (pipeline), or page 105 (Rx).
• If you want to key in a value for the detect level, make sure the detect level
function is highlighted (as shown above). Press the Go button and an input
screen appears. Key in a value for detect level. Press the Back button to save
your setting and exit the menu.
Phase-Angle Menu
See page 150.
Phase Angle