Teledyne 9110T instruction manual Span GAS for Multipoint Calibration

Model 9110T NOx Analyzer Getting Started

Zero Air generator (IZS) has a limited accuracy of about ±5%.

While NO2 permeation tubes may be sufficient for informal calibration checks, they are not approved by the US EPA as calibration sources for performing actual calibration of the analyzer.

SPAN GAS FOR MULTIPOINT CALIBRATION

Some applications, such as EPA monitoring, require a multipoint calibration where span gases of different concentrations are needed. We recommend using an NO gas of higher concentration combined with a gas dilution calibrator such as a Teledyne Model 700E. This type of calibrator mixes a high concentration gas with zero air to accurately produce span gas of the desired concentration. Linearity profiles can be automated with this model and run unattended overnight.

If a dynamic dilution system such as the Teledyne Model 700 is used to dilute high concentration gas standards to low, ambient concentrations, ensure that the NO concentration of the reference gas matches the dilution range of the calibrator.

Choose the NO gas concentration so that the dynamic dilution system operates in its mid-range and not at the extremes of its dilution capabilities.

EXAMPLE:

∙A dilution calibrator with 10-10000 dilution ratio will not be able to accurately dilute a 5000 ppm NO gas to a final concentration of 500 ppb, as this would operate at the very extreme dilution setting.

∙A 100 ppm NO gas in nitrogen is much more suitable to calibrate the 9110T analyzer (dilution ratio of 222, in the mid-range of the system’s capabilities).

Teledyne Analytical Instruments 58