Teledyne gfc 7000ta operation manual Software Operation, Adaptive Filter, Windows CE, API Firmware

Theory of Operation Model GFC7000TA Carbon Dioxide Analyzer

9.5. Software Operation

The Model GFC 7000TA Gas Filter Correlation Carbon Dioxide Analyzer has a high performance, VortexX86-based microcomputer running Windows CE. Inside Windows CE, special software developed by Teledyne Instruments interprets user commands via the various interfaces, performs procedures and tasks, stores data in the CPU’s various memory devices and calculates the concentration of the sample gas.

Windows CE
API FIRMWARE
Memory Handling	Analyzer Operations
	Calibration Procedures	PC/104 BUS
DAS Records
	Configuration Procedures
Calibration Data	Autonomic Systems
System Status Data
	Diagnostic Routines
		ANALYZER
		HARDWARE
	Interface Handling
Measurement	Sensor input Data
	Touchscreen/Display
Algorithm
	Analog Output Data
	RS232 & RS485	PC/104 BUS
	External Digital I/O
Linearization Table

Figure 9-18: Basic Software Operation

9.5.1. Adaptive Filter

The GFC 7000TA software processes the CO2 MEAS and CO2 REF signals, after they are digitized by the motherboard, through an adaptive filter built into the software. Unlike other analyzers that average the output signal over a fixed time period, the GFC 7000TA averages over a set number of samples, where each sample is 0.2 seconds. This is technique is known as boxcar averaging. During operation, the software automatically switches between two different length filters based on the conditions at hand. Once triggered, the short filter remains engaged for a fixed time period to prevent chattering.

During conditions of constant or nearly constant concentration the software, by default, computes an average of the last 750 samples, or approximately 150 seconds. This provides the calculation portion of the software with smooth stable readings. If a rapid change in concentration is detected the filter

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