Varian ProStar 325 UV-Vis, Руководство по обслуживанию

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ProStar325 Service Manual
Publication date 8 May 2003
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to the inactive state (as defined by the value of the “active sense”
parameter stored in the detector). Upon being triggered, relay
activation will occur at the time interval equal to the “peak sense
duration” parameter as stored in the method.
The peak sense relay can be activated from any of the following
sources (only one source can be active at any one time).
Peak Sense event – any of the peak sense events (start peak, end
peak, or peak valley) will activate the relay.
Level Sense event – The relay will be activated whenever the
absorbance value crosses over the threshold (in AU) which is set
by the user in the method.
Time slice event – Once timeslice has been turned on, it will
provide a periodic activation of the peak sense relay at an
interval defined in “TimeSlice period” within the method. Time
slice can be turned on and off from either runtime, peak sense, or
level sense.
Pulse event – Run timed programmed activation of the peak
sense relay as defined in the method.
4.3.5 Peak Sensing
The detector is able to perform peak sensing functions on the
data in real time. The purpose of the peak sensing function is to
control a fraction collector via the peak sensing relay.
The peak sensing functions will trigger the following events;
The start or end of a peak
A valley point
These events will either trigger the peak sense relay directly or
start a time slice function depending on the current method
definition. It will also mark the selected analog output with tick
marks.
Peak sense is applied after all data calculations, and before
bunching.
Peak sense does not account for filter delays. These are a user
responsibility in the method (relates to tube lengths).
4.3.6 Analog Output
Both of the analog outputs are for connection to a chart recorder.
This is particularly useful with the dual wavelength option so you
can monitor both channels. The parameters that can be modified
on the output include the AU represented by full scale deflection.
Tick marks are short positive and negative (up and down) spikes
generated at the recorder output that are used as event marks for
points of interest. Tick Marks on the recorder output are about
0.5 sec in duration to give comparable height on all chart
recorders. Tick marks occur at the following peak events:
•
Inject (method start) – positive spike (up)
•
Peak Start – positive (up)
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