Teledyne API Model 200AU NOX Analyzer Instruction Manual, 02293, Rev. F
5-20
5.3.4.2 Auto Range
Auto Range allows the NO, NOx, NO2 outputs to automatically range between a low range and a
high range. There is only one low range and one high range for all outputs. The Hi range mode is
signaled by a bit on the STATUS option, see Table 5-9. When the instrument output increases to
98% of the low range value, it will Auto Range into Hi range. In Hi range, when the output
decreases to 75% of low range, it will change to the lower range. If you select a Hi range that is
less than Low range, the M200AU will remain locked in Low range and behave as a Single
Range instrument.
To set up Auto Range press SETUP-RNGE-MODE-AUTO, then press ENTR. To set the values
press SETUP-RNGE-SET. The M200AU will prompt you for LO, then HI which are the lower
and upper ranges of Auto Range. Key in the values desired, then press ENTR.
5.3.4.3 Independent Ranges
Independent Ranges allows you to select different ranges for NO, NOx, and NO2.
To set up Independent Ranges press SETUP-RNGE-MODE-IND, then press ENTR. To set the
values press SETUP-RNGE-SET. The M200AU will prompt you for the range of NO, NOx and
NO2 channels. Key in the desired range for each channel, press ENTR after each value.
5.3.4.4 Concentration Units
The M200AU can display concentrations in ppb, ug/m3 units. Concentrations displayed in ug/m3
use 0° C, 760 mm-Hg for STP. Consult your local regulations for the STP used by your agency.
The following equations give approximate conversions:
NO ppb x 1.34 = NO ug/m3
NO ppm x 1.34 = NO mg/m3
NO2 ppb x 2.05 = NO2 ug/m3
NO2 ppm x 2.05 = NO2 mg/m3
NH3 ppb x 0.76 = NH3 ug/m3
NH3 ppm x 0.76 = NH3 mg/m3
To change the current units press SETUP-RNGE-UNIT from the SAMPLE mode and select the
desired units.