Teledyne 6200T - Sulfides Analyzer - Manual (Page 159)

6200T Total Sulfur Analyzer DAS and AICOM
Teledyne Analytical Instruments 159
7.1.2. DAS Parameters
Data parameters are types of data that may be measured and stored by the DAS. For
each Teledyne Analytical Instruments’s analyzer model, the list of available data
parameters is different, fully defined and not customizable. Appendix A-5 lists firmware
specific data parameters for the 6200T. The most common parameters are concentrations
of the measured gas (SO
2
), temperatures of heated zones (converter, sample chamber,
box temperature…), pressures and flows of the pneumatic subsystem and other
diagnostic measurements as well as calibration data (slope and offset) for each gas.
Most data parameters have associated measurement units, such as mV, ppb, cm³/min,
etc., although some parameters have no units. The only units that can be changed are
those of the concentration readings according to the SETUP-RANGE settings. Note that
the DAS does not keep track of the unit of each concentration value and DAS data files
may contain concentrations in multiple units if the unit was changed during data
acquisition.
Each data parameter has user-configurable functions that define how the data are
recorded (refer to Table 7-3).
Table 7-3: DAS Data Parameter Functions
FUNCTION EFFECT
PARAMETER Instrument-specific parameter name.
SAMPLE MODE INST : Records instantaneous reading.
AVG : Records average reading during reporting interval.
MIN : Records minimum (instantaneous) reading during reporting interval.
MAX : Records maximum (instantaneous) reading during reporting interval.
PRECISION Decimal precision of parameter value (0-4).
STORE NUM. SAMPLES OFF: stores only the average (default).
ON : stores the average and the number of samples in each average for a parameter. This
property is only useful when the AVG sample mode is used. Note that the number of
samples is the same for all parameters in one channel and needs to be specified only for
one of the parameters in that channel.
Users can specify up to 50 parameters per data channel (the 6200T provides about 30
parameters). However, the number of parameters and channels is ultimately limited by
available memory.
7.1.3. DAS Triggering Events
Triggering events define when and how the DAS records a measurement of any given
data channel. Triggering events are firmware-specific and are listed in Appendix A-5.
The most common triggering events are:
 ATIMER: Sampling at regular intervals specified by an automatic timer.
Most trending information is usually stored at such regular intervals, which
can be instantaneous or averaged.
 EXITZR, EXITSP, SLPCHG (exit zero, exit span, slope change):
Sampling at the end of (irregularly occurring) calibrations or when the
response slope changes. These triggering events create instantaneous data
points, e.g., for the new slope and offset (concentration response) values at
the end of a calibration. Zero and slope values are valuable to monitor
response drift and to document when the instrument was calibrated.