Operational Theory | BDS 3960 | |
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Note that instrument air at a pressure of 70 to 80 psig is needed to activate the proper valves.
Figure 2-6: Flow Diagram
2.4Electronics and Signal Processing
The Model BDS 3960 Oxygen Analyzer uses an 8051 microcontroller with 32 kB of RAM and 8 kB of ROM to control signal processing,, input/output, and display functions for the analyzer. Most of the processing power and decision making is done by the software running on the pocket PC (PPC). System power is supplied from a universal power supply module designed to be compatible with any international power source.
The signal processing electronics including the microprocessor, analog to digital, and digital to analog converters are located on the I/O board at the bottom of the case. The preamplifier board is mounted on top of the I/O board. These boards are accessible by sliding the front out. Figure
In the presence of oxygen the sensor generates a current. A current to voltage amplifier converts this current to a voltage which is further amplified in the second stage amplifier.
The output from the second stage amplifier is sent to an 12 bit analog to digital converter that is located in the same chip as the microprocessor. The amplifier board also reads the ambient temperature
Teledyne Analytical Instruments | 26 |