Teledyne API Model 200A NOX Analyzer Instruction Manual, 02246, Rev. G, DCN 5247
9.2.11 Slow Response
1. Contaminated or dirty sample delivery pneumatics.
A. Dirty/plugged sample filter or sample lines.
B. Dirty reaction cell.
2. Sample inlet line too long.
3. Wrong materials in contact with sample - use glass, stainless steel or Teflon.
4. Sample vent line located too far from instrument sample inlet. Locate sample inlet vent as
close as possible to analyzer.
5. Insufficient time allowed for purging of lines upstream of analyzer.
6. Leaking NO/NOx valve.
7. Insufficient time allowed for NO or NO2 cal gas source to become stable.
8. Moly converter temperature too low.
9. Miscalibration, see Table 7-7-1.
9.2.12 Analog Output Doesn't Agree with Display Concentration
The analog output is proportional to the range. Zero volts output corresponds to zero ppb, and 5
volts corresponds to the maximum range setting in ppb. If this is not observed do the following:
1. V/F board DAC's out of calibration. Do DAC calibration and Factory Calibration.
2. Analog outputs electrically loaded down causing voltage to sag. Could be due to imput
impedance to chart recorder or data logger being too low or improper grounding. The
Recorder and DAS outputs do not have separate output drivers, the problem could be the
combined load of both could be too high.
9-34
PRINTED DOCUMENTS ARE UNCONTROLLED