Teledyne ACCQPrep HP125 Installation And Operation Manual page 80

ACCQPrep HP125
Section 5 PeakTrak
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value. The peak will end when the detector signal drops
to .01 AU below the programmed value. This reduces the
potential of multiple peaks if a noisy signal oscillates
around the threshold value.
Note
If both Slope and Threshold peak detection methods are
checked, the system considers a peak to be present when any
one condition is met. This logical OR operator means that the
system will cut a peak when either the Slope condition is true,
or when the Threshold condition is true.
· Monitor — Enable this option to only use the
detection source as a monitor. When enabled, the
detection source will be displayed as a trace on the
gradient plot area, but will not be used to cut peaks.
· Peak Width — Select the average peak width setting.
Peak widths are measured at the baseline. The slope
detector will typically detect peak widths ranging
from about 0.2 to 2 times the peak width setting. For
example, if you entered a peak width of 1 minute, the
range would be 12 seconds to 2 minutes. For best
operation, the peak width should be set to just over
the average peak width being separated. For
instance, if the average peak width is 45 seconds, you
should enter a peak width of 1 minute. Sometimes
very small peaks need a larger peak width setting
since their small height results in a smaller slope
than larger peaks of the same width.
• All Wavelength Detection — Enable this option to detect
peaks within a user-selected range of wavelengths.
When enabled, click the D
additional settings. These settings include the
slope-based and peak width options described in λ
λ
above. Peak width is used to determine solvent absor-
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bance suppression. Peaks that are twice the peak width
are deemed to be solvent or other baseline drift and
their absorbance spectrum will be subtracted as an
assumed baseline spectrum. Additionally, you can type
or select the minimum and maximum wavelengths
limits in nanometers. This eliminates areas of little
spectral information from the all wavelength detection
signal resulting in a stronger signal.
• Mass Spectrometer – Enable this option to monitor or
detect compounds with a PurIon mass spectrometer
system (PurIon systems only).
· Threshold – signal level used to detect a peak. This is
based on the baseline noise. The baseline noise is
measured during the first column volume; this is
multiplied by the value entered in the threshold
control to generate a trigger value. A peak is collected
if the signal is greater than this trigger value.
button to configure
ETAILS
and
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