Check the helium gas and nitrogen gas regulators to determine how much gas is in each tank.

CAUTION

Before you operate the MS, verify that there is sufficient nitrogen for the API source. Do not operate the MS without nitrogen gas flow as this can damage the source and front end optics due to particulate matter in the atmosphere.

If the system runs out of nitrogen gas while you are acquiring scans in the Tune application, a prompt appears with a warning that the nitrogen supply is probably empty. If you are running an acquisition sequence, the data system completes the current run. The system does not proceed to the next sample because the MS cannot return to the Ready state when the nitrogen set point cannot be reached. Meanwhile, the MS continues scanning.

The following table describes the procedures for checking the gas supplies.

Procedures for Checking the Gas Supplies

Gas

Procedure

UHP Helium gas

Procedure

  1. Check the regulator to make sure there is sufficient UHP Helium gas. Replace the tank when the tank pressure falls below 3,447 kPa (500 psi).
  2. Verify that the pressure of helium gas reaching the MS is 275 ±70 kPa (40 ±10 psi). If necessary, adjust the pressure using the tank pressure regulator.

Nitrogen gas

Procedure

  1. Check the regulator of the nitrogen gas tank or liquid nitrogen boil-off tank to make sure that there is sufficient gas. If necessary, replace the tank.
  2. Verify that the pressures of nitrogen gases reaching the MS are as follows:
  3. UHP nitrogen gas pressure: 345 ±70 kPa (50 ±10 psi)
  4. HP nitrogen gas pressure: 690 ±140 kPa (100 ±20 psi)

If necessary, adjust the pressure using the tank pressure regulator.

When operating 24 hours and 7 days a week, the system typically consumes the following amounts of gas per day:

  • UHP nitrogen: approximately 46 L/day (1.62 ft3)
  • HP nitrogen: 11,500–26,700 L/day (406–943 ft3)