Modular Oven Model Pecm-Dc Led Locations; Leak Testing - Siemens Maxum II Manual

General Maintenance and Troubleshooting

4.2 Leak Testing

4.1.2.4

Modular Oven Model PECM-DC LED Locations

LED Status Indicators
The PECM-DC LED locations are shown below.
4.2 Leak Testing
A gas chromatograph is a complex device with many gas fittings. Under normal thermal and
vibration stresses, these can develop leaks. Therefore, periodic leak testing must be performed
in accordance with local safety ordinances and rules.
General Overview of Leak Test Methods
An overall static pressure test of the analyzer installation can detect if a leak exists somewhere
in the system.
1. Install caps on all vents.
2. Make sure the system is properly purged.
3. Increase EPC settings to maximum, or to pressures specified by safety rules.
4. Open the gas supply valves and allow the entire system to be pressurized.
5. Close gas supply valves and watch for a pressure drop over a minimum time period. This
time period will be application specific and may be specified in local safety rules.
6. Operate the column and sample valves to ensure all parts of the system are pressurized.
Some pressure drop may be seen upon valve operation; shortly afterward the pressure
should stabilize and hold the current pressure.
7. If no pressure drop is observed, then the test can be ended, the vent caps removed, and
the analyzer safely placed into service.
8. If a pressure drop is observed, a leak exists. Leaks can affect the application reliability and
the safe operation of the analyzer. The leak must be isolated and repaired.
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Maxum edition II Analyzer General Maintenance
Manual, August 2018, A5E42019842001