Teledyne 9110TH - Nitrogen Oxides Analyzer - Manual (Page 204)

Model 9110TH NOx Analyzer Calibration Procedures
Teledyne Analytical Instruments 184
The following example sets sequence #2 to carry out a zero-span calibration every other
day starting at 14:00 on 01 January, 2003, lasting 30 minutes (15 for zero and 15 for
span). This sequence will start 30 minutes later each day.
Table 5-4: Example Auto-Cal Sequence
MODE AND ATTRIBUTE VALUE COMMENT
SEQUENCE 2 Define sequence #2
MODE ZERO-HI Select zero and span mode
TIMER ENABLE ON Enable the timer
STARTING DATE 01-JAN-03 Start on or after 01 January 2003
STARTING TIME 14:00 First sequence starts at 14:00 (24-hour clock format)
DELTA DAYS 2 Repeat this sequence every 2 days
DELTA TIME 00:30
Repeat sequence 30 minutes later each time
(every 2 days and 30 minutes)
DURATION 15.0
Each sequence step will last 15 minutes (total of 30 minutes when
using zero-span mode)
CALIBRATE ON
The instrument will recalculate the slope and offset values for the
NO and NOX channel at the end of the AutoCal sequence.
Please the following suggestions for programming the AutoCal feature.
 The programmed Starting Time must be 5 minutes later than the real time
clock.
 Avoid setting two or more sequences at the same time of the day. Any new
sequence which is initiated from a timer, the COM ports, or the contact
closures will override any sequence in progress. that two sequences with
different daily increments may eventually overlap.
 If at any time an illegal entry is selected, (for example: Delta Days > 366)
the ENTR button will disappear from the display.
 With CALIBRATE turned on, the state of the internal setup variables
DYN_SPAN and DYN_ZERO is set to ON and the instrument will reset
the slope and offset values for the NO and NO
X
response each time the
AutoCal program runs. This continuous re-adjustment of calibration
parameters can often mask subtle fault conditions in the analyzer. It is
recommended that, if CALIBRATE is enabled, the analyzer’s test
functions, slope and offset values be checked frequently to assure high
quality and accurate data from the instrument.