Thermo Fisher Scientific recommends that you keep the system under vacuum even during long periods when it is not in use. Although not recommended, you can shut down the MS when you are not planning to use it for an extended period of time.

IMPORTANT

For short periods between use, place the MS in Standby mode. Do not shut down the MS, as pumping down the system takes many hours.

NOTE

Thermo Fisher Scientific field service engineers must shut down the MS to service components under vacuum.

Procedure

  1. Follow the procedure in Place the MS in Standby mode for short periods between use.
  2. Place the Electronics service switch in the Service Mode (down) position.
  3. Placing the Electronics service switch in the Service Mode turns off all LEDs on the front panel and the power to the nonvacuum system electronics.
  4. Turn off the Main Power switch.
  5. Electronics switch in the Service Mode position and Main Power switch in the Off position
    12
    No.DescriptionNo.Description

    1

    Electronics switch in the Service Mode position (down)

    2

    Main Power switch in the Off position

  6. The following occur:
  7. All power to the MS, including the turbomolecular pumps, turns off. In addition, the forepumps turn off.
  8. After approximately 60 seconds, power to the vent valve solenoid shuts off, the vent valve opens, and the vacuum manifold vents with filtered air. You might hear a hissing sound.
  9. After about 5 minutes, the vacuum manifold is at atmospheric pressure.
  1. Unplug the mass spectrometer’s power cord from the electrical outlet.

  2. CAUTION

    Do not disconnect the power supply cord from the MS while the other end is still plugged into the electrical outlet.

  3. TIP

    When performing routine or preventive system maintenance on the MS, you do not need to turn off the LC, gases, data system, or autosampler.

  1. If you plan to leave the system off for an extended period of time, Thermo Fisher Scientific recommends that you also turn off the LC, the autosampler, the data system computer, and the gases, as follows:
  2. Turn off the optional LC system and autosampler as described in their manuals. Then, shut down the data system computer and turn off the monitor.
  3. Close the argon and nitrogen gas supplies at their tanks.