38 DECADE user manual, edition 9
switched back to ‘load’ to enable continuous refilling of the injection loop. At
time 1:26 the sensitivity is increased by a factor of 100 from 50 nA/V to 0.5
nA/V, together with an auto zero command. After passage of the small peak,
the range is switched back to 50 nA/V. At t=3:05 the end of the
chromatographic run is programmed in the ‘AUTO SET’ screen, using the
‘CycleTime’ parameter.
If the
integrator
range is switched between µA, nA or pA, simultaneously with
an auto zero command this may result in an inappropriate baseline setting.
Setting the range first is recommended in such case.
Fig. 10. Example of range programming to maintain the recorder resolution. In chromatogram (A) a
range setting of 50 nA/V is used, in chromatogram (B) the output range is automatically switched
during the run resulting in a considerable improvement of the output resolution of peak 1.
Table VI. time file used for output resolution programming.
time int.
range
rec.
range
rise
time
valve auto
zero
offset output E
cell
00:00
nA
50 nA
1 s
inject
set
00%
0000
0.80 V
00:10
nA
50 nA
1 s
load
not
00%
0000
0.80 V
01:26
nA
0.5 nA
1 s
load
set
00%
0000
0.80 V
01:55
nA
50 nA
1 s
load
set
00%
0000
0.80 V
03:05
Cycle Time (end of run)
Drift monitor
The AUTO mode of the DECADE is equipped with a drift monitor, which puts
the detector on ‘hold’ when the baseline is drifting. The drift monitor is only
active at the beginning of a time file, both in the master and slave mode. After
starting a time file the baseline is monitored during one minute and the ‘wait..’
message is displayed. When the baseline is not within the pre-set limit, the
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com