Model NGA2000 TO2
Instruction Manual
3-3 STARTUP PROCEDURE
Establish sample or zero gas flow through the analyzer module at a nominal flow rate of 2 SCFH (1 l/min). Allow gas to flow for 15 to 30 seconds before applying power. Apply power to the TO2 Analyzer Module.
Upon initial startup, the separate modules, Con- troller Board and network
Establish that sample flow rate is within specifi- cations (see Section
difference, the diffusion change can be com- pensated in software. The GSF can be entered manually or calculated automatically. Calcula- tion of the GSF requires the user to enter the sample gas composition. In most applications, the GSF is not required. However, some back- grounds exhibit significantly different diffusion characteristics versus nitrogen (such as helium or hydrogen) and the GSF may improve per- formance.
Under the Technical Level Configuration sub- menu, select Diagnostic menus... and then se- lect Analyzer Module Diagnostics…. In the Analyzer Module Diagnostics
3-4 QUICK START FEATURE
This analyzer module is equipped with a quick start feature which allows the sensor to begin measuring low ppm oxygen faster. This feature can be used when the analyzer is first turned on to decrease the time required for the sensor to reach equilibrium. This function is most effec- tive for gas sample measurements below 100 ppm. To maintain sensor life, it is recom- mended that this feature be used no more than two times in any 24 hour period.
Under the Basic Controls
3-5 GAS SCALE FACTOR (GSF)
The Gas Scale Factor is used to correct for background gases other than nitrogen. When the background of the sample is other than ni- trogen, the diffusion rate of oxygen into the sen- sor changes. By correcting for the background
Once you have entered all the background composition information, move the cursor to Compute new adjusted gas scale factor! and press the ↵ key and the analyzer module will automatically calculate the new gas scale factor.
3-6 CALIBRATION
The TO2 analyzer module is fully factory cali- brated using certified gas standards prior to shipment. If the analyzer is operated within its specified operating conditions, no calibration is required. The zero calibration is very stable and does not require checking more than once a year. Depending upon the nature of your appli- cation, it may be beneficial to verify the span calibration of the analyzer module every
Under the Expert Controls
Rosemount Analytical Inc. A Division of Emerson Process Management | Startup and Operation |