Teledyne API Model 200AU NOX Analyzer Instruction Manual, 02293, Rev. F
7-1
7 CALIBRATION & ZERO/SPAN CHECKS
There are several ways to check and adjust the calibration of the M200AU. These different
methods are summarized in Table 7-1. In addition, all of the methods described in this section
can be initiated and controlled via the RS-232 port.
We strongly recommend that SPAN CALIBRATION be done with NO span gas. SPAN
CHECKS can be done with either NO only, NO2 only or a mixture of NO and NO2 (GPT).
Zero air used for all calibration procedures, including GPT, should have 1 ppt NO and NO2, less
than 1 ppt of major interferents such as SO2, NH3, and hydrocarbons and a dew point of -5o C or
less. The calibration gasses should be from a reliable supplier, since the quality of the tank
concentration values ultimately determines the accuracy of the analyzer. EPA protocol
calibration gasses should be used for EPA monitoring, see Section 7.6.
NOTE
If you are using the M200AU for EPA monitoring, only the
calibration method described in Section 7.6 should be used.
NOTE
If there are any problems completing any of the following procedures,
refer to Section 9.2.8 and 9.2.9 - Unable to Span or Zero.