7-30
2000-OSM, F1
0120
Noise Calc
On
0125 Noise
Calc
Off
This function samples the baseline to determine the random noise level of the baseline and is
applicable only to slope detection.
0128 Auto
Zero
N/A
This function establishes a baseline zero reference point in the controller. It in effect compensates for
the detector offset from electrical zero. Should this function fail or not be scheduled, errors could
occur in gating, peak detection, post analysis calculations and peak concentration calculations as a
result of errors in baseline correction.
0130 Skp
Nxt,Str= Nine
The function at time 0130 causes the next timed function at 0132 to not be executed. Thus, when the
next stream is stream 9 (a blank run), the sample valve on command will not occur and a sample will
not be injected. Should this function not be scheduled, a whole chromatogram would be saved as a
blank run. The result would be a total or near cancellation of the analysis in the post analysis
calculation.
0132 Valve
On
One
This function causes the sample injection by inserting the sample volume contained in the machined
groove in valve stem into the injection chamber of the sample valve. Once in the injection chamber,
the liquid sample is vaporized and carried into the column train by carrier gas. Should this function
fail or not be scheduled, no sample injection would occur.
0155 Valve
Off
One
This function withdraws the sample machined groove from the injection chamber into the sample
chamber, where liquid sample continually flows across the stem in preparation for the next injection.
Should this function fail or not be scheduled, only the initial sample injection would occur; the sample
loop would never be refilled.
0165 Baseline
Proj
Forward
This function is used in baseline correction of individual gated peaks.
0172
Forced Gate
On @ Valley
This function immediately forces integration to begin and designates the peak topology for the start to
be a valley, doing a perpendicular drop to the baseline.
0175
Component
One
This function designates which component is being integrated at gate on command.
0178
Forced Gate
Off @ Valley
This function immediately forces integration to stop and designates the peak end and topology to be a
valley, doing a perpendicular drop to baseline.
NOTE
All other gate and component descriptions are similarly defined.
TP 34: VENT BACK PRESSURE
1. Ensure FID or TCD detector vent is vented to atmospheric pressure.
2. Check for insect infestations in vent or atmospheric vent.
3. Replace flame arrester. Check for water in the detector. If necessary clean FID (see “FID
REPAIR/Cleaning the Collector” in Section 8).