Leak Sensor Assembly (LC/MS)

The LC/MS includes a leak sensor assembly to detect leaks from the stream selection valve, manual injection valve, LC inlet, and calibrant delivery system (CDS) valves.

The leak sensor assembly comprises:

  • Drip (upper) tray
  • Catch (lower) tray
  • Sensors

The drip tray collects leaks from the stream selection valve, manual injection valve, and LC inlet. Any liquid that falls into the drip tray drips down into the catch tray.

The catch tray collects and holds any leaks from the calibrant delivery system (CDS) valves and any liquid that drips down from the drip tray.

There are two thermal conductivity sensors, one inside the catch tray and one outside the catch tray. Signals from the two sensors are continuously compared. If the sensor inside the lower tray gets wet, its signal changes. If the signals from the two sensors do not match, it is interpreted as a leak.

If the leak sensor detects a leak, it will turn off the LC pumps and indicate an error for both the LC and MS. It will also stop any method or sequence that is currently running. A message indicating a leak is written to the message line but it is typically overwritten by subsequent related messages. The message is also written to the current logbook where it can be viewed.

To reset the system after a leak has been detected, follow these steps:

  1. Locate and repair the leak. Check the inlet fittings, the selection valve, the CDS valves, the Calibrant bottle, and the tubing for leaks.
  2. Thoroughly dry the drip tray, the catch tray, and the sensor in the catch tray. Once everything is dry, the MS status should change to ready (green).
  3. Restart the LC pumps by selecting System On from the Instrument menu. The LC pump status will indicate ready (green) when the pumps are back on. The MS status will also indicate ready (green).

See Also

Troubleshooting (LC/MS)