Theory of Operation

Model GFC7000TA Carbon Dioxide Analyzer

Measurement

Reference

Pulses

Pulses

IR Beam

Pulses

Segment Sensor

Pulses

MR Sensor

Pulses

Figure 9-12: Segment Sensor and M/R Sensor Output

Schmidt Triggers

To ensure that the waveforms produced by the Segment Sensor and the M/R Sensor are properly shaped and clean, these signals are passed through a set of Schmidt Triggers circuits.

9.3.3.4. IR Photo-Detector

The IR beam is converted into an electrical signal by a cooled solid-state photo-conductive detector. The detector is composed of a narrow-band optical filter, a piece of lead-salt crystal whose electrical resistance changes with temperature, and a two-stage thermo-electric cooler.

When the analyzer is on, a constant electrical current is directed through the detector, The IR beam is focused onto the detector surface, raising its temperature and lowering its electrical resistance that results in a change in the voltage drop across the detector.

During those times that the IR beam is bright, the temperature of the detector is high; the resistance of the detector is correspondingly low and the its output voltage output is low. During those times when the IR beam intensity is low or completely blocked by the GFC Wheel mask, the temperature of the detector is lowered by the two-stage thermo-electric cooler, increasing the detectors resistance and raising the output voltage.

9.3.4. Synchronous Demodulator (Sync/Demod) Assembly

9.3.4.1. Overview

While the photo-detector converts fluctuations of the IR beam into electronic signals, the Sync / Demod Board amplifies these signals and converts them into usable information. Initially the output by the photo- detector is a complex and continuously changing waveform made up of Measure and Reference pulses. The sync/demod board demodulates this waveform and outputs two analog DC voltage signals, corresponding to the peak values of these pulses. CO2 MEAS and CO2 REF are converted into digital signals by circuitry on the motherboard then used by the CPU to calculate the CO2 concentration of the sample gas.

Additionally the synch/demod board contains circuitry that controls the photo-detector’s thermoelectric cooler as well as circuitry for performing certain diagnostic tests on the analyzer.

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Teledyne gfc 7000ta operation manual Synchronous Demodulator Sync/Demod Assembly, IR Photo-Detector, Overview
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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.
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