Skip to main content

Q-Tof Tof Vacuum out of range Part 2 - WKB2649

Article number: 2649


  • The Tof penning gauge reads 1e-8 mBarr, a large reading
  • There is an error message in the MS console or at the bottom of the tune page that reads 'Tof vacuum out of range'


  • Q-Tof
  • MassLynx
  • Tof


The penning gauge is shorted and not reading the actual vacuum. The short is usually from some sort of debris in the penning gauge


  1. Vent.
  2. Remove the panels to see the Tof Penning Gauge. 
  3. Disconnect the rj45 cable going to the penning gauge.
  4. Rotate the orange or grey magnetic housing anti-clockwise and pull it off.

penning gauge.PNG

  1. Remove the penning gauge, and replace it (part number 6061138).

penning gauge body tube.PNG

  1. Re-assemble the penning gauge (housing and cable), and put the panels back on.
  2. Pump down. 
  3. Check the Tof vacuum reading on the tune page. It should read e-6 or e-7 mBar depending on how long it has been pumping.
  4. The instrument can go into operate if the Tof vacuum is less than 1.2 e-6 mBar and has been pumping for at least an hour. 


If this did not work, see QTof Tof Vacuum out of range Part 1.

Not able to find a solution? Click here to request help.