Status phrase for a turbomolecular pump running at its rated rotational speed, usually signalled by a controller relay or a normal-operation light. Interlocks commonly wait for this signal before opening the high vacuum valve or allowing an ion gauge to switch on. A turbo that never comes up to speed points to a high foreline pressure, a leak or worn bearings.
Turbo's still not at speed after twenty minutes, it's stuck at 60 percent, go look at the foreline.
Also heard as
- up to speed
- normal speed
Related terms
Turbomolecular pump
High vacuum pump whose rotor blades spin at tens of thousands of rpm and bat molecules toward the exhaust.
Spin down
Of a turbo pump, to coast down from full speed after it is switched off, which takes many minutes on its own.
Backing pump
Pump that keeps the exhaust of a turbo, diffusion or Roots pump below its maximum allowed pressure.
Foreline
Pipe that connects the exhaust of a high vacuum or booster pump to its backing pump.