Teledyne 9110TH - Nitrogen Oxides Analyzer - Manual (Page 92)

Model 9110TH NOx Analyzer Operating Instructions
Teledyne Analytical Instruments 72
4.7.2.5. Sample Period and Report Period
The DAS defines two principal time periods by which sample readings are taken and
permanently recorded:
 SAMPLE PERIOD: Determines how often DAS temporarily records a
sample reading of the parameter in volatile memory. The SAMPLE
PERIOD is set to one minute by default and generally cannot be accessed
from the standard DAS front panel menu, but is available via the
instruments communication ports by using APICOM or the analyzer’s
standard serial data protocol.
SAMPLE PERIOD is only used when the DAS parameter’s sample mode is set for
AVG, MIN or MAX.
 REPORT PERIOD: Sets how often the sample readings stored in volatile
memory are processed, (e.g. average, minimum or maximum are
calculated) and the results stored permanently in the instrument’s Disk-on-
Module as well as transmitted via the analyzer’s communication ports. The
REPORT PERIOD may be set from the front panel.
If the INST sample mode is selected the instrument stores and reports an instantaneous
reading of the selected parameter at the end of the chosen REPORT PERIOD
In AVG, MIN or MAX sample modes, the settings for the SAMPLE PERIOD and the
REPORT PERIOD determine the number of data points used each time the average,
minimum or maximum is calculated, stored and reported to the com ports. The actual
sample readings are not stored past the end of the of the chosen REPORT PERIOD.
Also, the SAMPLE PERIOD and REPORT PERIOD intervals are synchronized to
the beginning and end of the appropriate interval of the instruments internal clock.
 If SAMPLE PERIOD were set for one minute the first reading would
occur at the beginning of the next full minute according to the instrument’s
internal clock.
 If the REPORT PERIOD were set for of one hour the first report activity
would occur at the beginning of the next full hour according to the
instrument’s internal clock.
EXAMPLE: Given the above settings, if DAS were activated at 7:57:35 the first sample
would occur at 7:58 and the first report would be calculated at 8:00 consisting of data
points for 7:58, 7:59 and 8:00.
During the next hour (from 8:01 to 9:00) the instrument will take a sample reading every
minute and include 60 sample readings.
When the STORE NUM. SAMPLES feature is turned on the instrument will also store
how many sample readings were used for the AVG, MIN or MAX calculation but not
the readings themselves.