Teledyne GFC 7001EM operation manual Diag  Signal I/O Using the Diagnostic Signal I/O Function

Troubleshooting & Repair Model GFC7001E Carbon Dioxide Analyzer

13.1.3.DIAG  SIGNAL I/O: USING THE DIAGNOSTIC SIGNAL I/O FUNCTION

The signal I/O diagnostic mode allows access to the digital and analog I/O in the analyzer. Some of the digital signals can be controlled through the keyboard. These signals, combined with a thorough understanding of the instruments Theory of Operation (found in Section Error! Reference source not found.), are useful for troubleshooting in three ways:

The technician can view the raw, unprocessed signal level of the analyzer’s critical inputs and outputs.

Many of the components and functions that are normally under algorithmic control of the CPU can be manually exercised.

The technician can directly control the signal level Analog and Digital Output signals.

This allows the technician to observe systematically the effect of directly controlling these signals on the operation of the analyzer. The following flowchart shows an example of how to use the Signal I/O menu to view the raw voltage of an input signal or to control the state of an output voltage or control signal.

Figure 13-2: Example of Signal I/O Function

NOTE

Any I/O signals changed while in the signal I/O menu will remain in effect ONLY until signal I/O menu is

exited. The Analyzer regains control of these signals upon exit.

Teledyne Analytical Instruments 273