Model 9110T NOx Analyzer

Data Acquisition System (DAS) and APICOM

7.1.3.3. Editing DAS Parameters

Data parameters are types of data that may be measured and stored by the DAS. For each TAI'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 9110T. DAS parameters include data such as NOx, NO and NO2 concentration measurements, temperatures of the various heaters placed around the analyzer, pressures and flows of the pneumatic subsystem and other diagnostic measurements as well as calibration data such as stability, slope and offset.

Most data parameters have associated measurement units, such as mV, ppb, cm³/min, etc., although some parameters have no units (e.g. SLOPE). With the exception of concentration readings, none of these units of measure can be changed. To change the units of measure for concentration readings, see Section 5.4.3.4.

Note

DAS does not keep track of the units (i.e. PPM or PPB) of each

 

concentration value. Therefore, DAS data files may contain concentration

 

data recorded in more than one type of unit if the units of measure were

 

changed during data acquisition

Each data parameter has user-configurable functions that define how the data are recorded which are listed in 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.

 

SDEV: Records the standard deviation of the data points recorded during the reporting interval.

 

MIN: Records minimum (instantaneous) reading during reporting interval.

 

MAX: Records maximum (instantaneous) reading during reporting interval.

PRECISION

0 to 4: Sets the number of digits to the right decimal point for each record.

 

Example: Setting 4; “399.9865 PPB”

 

Setting 0; “400 PPB”

STORE NUM.

OFF: Stores only the average (default).

SAMPLES

ON: Stores the average and the number of samples in used to compute the value of the

 

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 9110T provides about 40 parameters). However, the number of parameters and channels is ultimately limited by available memory.

Data channels can be edited individually from the front panel without affecting other data channels. However, when editing a data channel, such as during adding, deleting or editing parameters, all data for that particular channel will be lost, because the DAS can store only data of one format (number of parameter columns etc.) for any given channel. In addition, a DAS configuration can only be uploaded remotely as an entire set of channels. Hence, remote update of the DAS will always delete all current channels and stored data.

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Teledyne 9110T instruction manual Changed during data acquisition, DAS Data Parameter Functions