CAI 600-NDIR, Руководство пользователя

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Section 2 Model 601/601P/602/602P/603 NDIR Analyzer
California Analytical Model 600_NDIR_Series_v10.0 CE Operators Manual
Page 20 of 86
2.6. Electronics
The sinusoidal output signal of the detector’s microflow sensor is transmitted to the AC
amplifiers on the main circuit board. The signal frequency is related to the rate of the beam-
interrupting chopper blade. The signal amplitude is related to the measured gas
concentrations in the sample cell.
This signal is amplified by successive AC amplifiers and then demodulated and filtered. The
resulting DC signal is further amplified and fed into two output buffer amplifiers. The DC signal
output of the printed circuit board is the input to a microprocessor. Here it is digitized and
linearized for digital display
The digitized information is then fed to a D/A Converter so it can be isolated and converted to
a 0-10 VDC or 4-20 mA output. This output (along with optional alarm contacts) is sent to the
28-pin output connector located on the rear panel of the analyzer for customer connection.
Figure 2-4 Block Diagram