Theory of Operation

Model GFC7000TA Carbon Dioxide Analyzer

includes, by default, the last 48 samples, approximately 10 seconds of data, to allow the analyzer to more quickly respond. If necessary, these boxcar lengths can be changed between 1 and 1000 samples but with corresponding tradeoffs in rise time and signal-to-noise ratio (contact customer service for more information).

Two conditions must be simultaneously met to switch to the short filter. First the instantaneous concentration must exceed the average in the long filter by a fixed amount. Second the instantaneous concentration must exceed the average in the long filter by a portion, or percentage, of the average in the long filter.

9.5.2. Calibration - Slope and Offset

Calibration of the analyzer is performed exclusively in software.

During instrument calibration (see Section 7) the user enters expected values for zero and span via the front panel touchscreen and commands the instrument to make readings of calibrated sample gases for both levels. The readings taken are adjusted, linearized, and compared to the expected values, With this information the software computes values for instrument slope and offset and stores these values in memory for use in calculating the CO2 concentration of the sample gas.

The instrument slope and offset values recorded during the last calibration can be viewed by pressing the following touchscreen button sequence:

SAMPLE

RANGE = 50.0 MGM

CO2

=XX.XX

 

 

 

 

 

 

 

 

SAMPLE

TIME = 16:23:34

CO2

=XX.XX

 

 

 

 

 

SAMPLE

OFFSET = 0.000

CO2

=XX.XX

 

 

 

 

 

SAMPLE

SLOPE = 1.000

CO2

=XX.XX

 

 

 

 

 

9.5.3. Measurement Algorithm

Once the IR photo-detector is signal is demodulated into CO2 MEAS and CO2 REF by the sync/demod board and converted to digital data by the motherboard the GFC 7000TA analytical software calculates the ratio between CO2 MEAS and CO2 REF. This value is compared to a look-up table is used, with interpolation, to linearize the response of the instrument. The linearized concentration value is combined with calibration slope and offset values, then normalized for changes in sample gas pressure to produce the final CO2 concentration. This is the value that is displayed on the instrument front panel display and is stored in memory by the analyzer’s DAS system.

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Teledyne gfc 7000ta operation manual Calibration Slope and Offset, Measurement Algorithm

gfc 7000ta specifications

The Teledyne GFC 7000TA is a cutting-edge, high-performance gas flow calibrator designed for both laboratory and field applications. This instrument is renowned for its accuracy, versatility, and reliability, making it an ideal choice for various industries, including aerospace, environmental monitoring, and manufacturing.

One of the standout features of the GFC 7000TA is its advanced measurement technology. It utilizes state-of-the-art thermal mass flow meters, which allow for precise fluid measurement across a wide range of flow rates. This technology ensures highly accurate readings, which are essential for applications requiring stringent compliance with regulatory standards.

The GFC 7000TA is capable of accommodating various types of gases, making it particularly versatile. Users can calibrate flow for gases such as air, nitrogen, or carbon dioxide, providing flexibility in a multitude of applications. The device also supports dual-channel capabilities, allowing simultaneous measurement and calibration of two different gas types, enhancing productivity and efficiency in processes.

Another notable characteristic of the GFC 7000TA is its user-friendly interface. Equipped with a high-resolution touchscreen display, the device offers intuitive navigation and data visualization. Users can easily set parameters, view real-time measurements, and generate printed reports. This interface reduces the learning curve for new operators, allowing organizations to implement the GFC 7000TA with minimal training.

In addition to its advanced measuring capabilities, the GFC 7000TA features a robust design for durability in harsh environments. The instrument is compliant with various international standards, ensuring its reliability and performance in various conditions. Its portable form factor makes it convenient for fieldwork, while the rugged construction provides peace of mind for users working in demanding settings.

The GFC 7000TA also incorporates modern connectivity options. With built-in USB and Ethernet ports, users can easily integrate the device into their existing systems for data logging and remote monitoring. This connectivity feature enables real-time data access and enhances the potential for analysis and optimization of gas flow systems.

In summary, the Teledyne GFC 7000TA is a high-performance gas flow calibrator characterized by its advanced thermal mass flow measurement technology, versatility in accommodating various gases, user-friendly interface, and robust design. With its modern connectivity features, this instrument stands out as a vital tool for professionals seeking precision and reliability in gas flow applications.