Teledyne gfc 7000ta operation manual General Troubleshooting Hints

Troubleshooting Model GFC7000TA Carbon Dioxide Analyzer

10. TROUBLESHOOTING & REPAIR PROCEDURES

This contains a variety of methods for identifying the source of performance problems with the analyzer. Also included in this are procedures that are used in repairing the instrument.

CAUTION

The operations outlined in this section are to be performed by qualified maintenance

personnel only.

CAUTION

Risk of electrical shock. Disconnect power before performing the following

operations.

10.1. General Troubleshooting Hints

The analyzer has been designed so that problems can be rapidly detected, evaluated and repaired. During operation, the analyzer continuously performs self-check diagnostics and provides the ability to monitor the key operating parameters of the instrument without disturbing monitoring operations.

A systematic approach to troubleshooting will generally consist of the following four steps:

1.Note any WARNING MESSAGES and take corrective action as required.

2.Examine the values of all TEST functions and compare to factory values. Note any major deviations from the factory values and take correction action as required.

3.Use the internal electronic status LED’s to determine whether the CPU and I2C buses are running, and if the sync/demodulator and relay board are operating properly. Verify that the DC power supplies are operating properly by checking the voltage test points on the relay board. Please note that the analyzer’s DC power wiring is color-coded and these colors match the color of the corresponding test points on the relay board.

4.SUSPECT A LEAK FIRST! Data from Teledyne Instruments’ service department indicates that 50% of all problems are eventually traced to leaks in the pneumatic connections and gas lines of the analyzer itself, the source of zero air, span gases or sample gas delivery system.

Check for gas flow problems such as clogged or blocked internal/external gas lines, damaged seals, punctured gas lines, a damaged pump diaphragm, etc.

5.Follow the procedures defined in Section 11.5 for confirming that the analyzer’s basic components are working (power supplies, CPU, relay board, sync/demod board, touchscreen/display, GFC wheel motor, etc.). See Figure 3-3 for general layout of components and sub-assemblies in the analyzer. See the wiring list and diagram in Appendix D of this manual.

Teledyne Analytical Instruments 217