4 Operating in EI Mode
To View MSD Temperature and Vacuum in Manual Tune
90 5977C GC/MSD Operating Manual
3 To change a temperature Setpoint or Limit enter the new parameters and
click Apply.
Temperature setpoints or limits can not be changed until the foreline pressure is
less than 300 mTorr, or the turbo pump is running at least 80% speed. MSD
heaters remain off as long as the diffusion pump is cold or the turbo pump is
operating at less than 80%. Normally, the foreline pressure will be below
100 mTorr, or the turbo pump speed will be at 100%.
The MSD heaters turn on at the end of the pumpdown cycle, and turn off at the
beginning of the vent cycle. The reported setpoints will not change during venting
or pumpdown, even though both MSD zones are turned off.
Figure 24. HES manual tune values tab