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Model 400E Ozone Analyzer
Instruction Manual
THEORY OF OPERATION
P/N 04316 Rev: B
239
Keypad
The row of eight keys just below the Vacuum Florescent Display are the main
method by which the user interacts with the analyzer. These keys are context
sensitive and are dynamically re-defined as the user moves around in the software
menu structure.
Front Panel States LED’s
There are three status LED’s located in the upper right corner of the Model 400E’s
Front Panel. They are:
Table 10-2: Front Panel Status LED’s
Name
Color
State
Definition
SAMPLE Green
Off
On
Blinking
Unit is not operating in Sample Mode, iDAS is disabled.
Unit is operating in Sample Mode, Front Panel Display
being updated, iDAS data being stored.
Unit is operating in Sample Mode, Front Panel Display
being updated, iDAS Hold-Off mode is ON, iDAS disabled
CAL
Yellow
Off
On
Blinking
Auto Cal disabled
Auto Cal enabled
Unit is in calibration mode
FAULT
Red
Off
Blinking
No warnings exist
Warnings exist
10.5.
Software Operation
The Model 400E Ozone Analyzer is at its heart a high performance, 386-based
microcomputer running MS-DOS. Inside the DOS shell, special software developed
by T-API interprets user commands vie the various interfaces, performs procedures
and tasks, stores data in the CPU’s various memory devices and calculates the
concentration of the sample gas.