Another advantage of this increased compression means higher backing pressures can be tolerated by the TMP, even up to a few mbar. Consequently, some diaphragm pumps are now capable of acting as a forevacuum pump for this design of pump. Diaphragm pumps are often used in portable “dry” leak detectors and compact high vacuum pumping systems.
All turbopumps require a frequency controller to provide the high rotational speeds demanded by these pumps. Conventionally, these were stand-alone units, but increasingly the controllers have been integrated onto the pump as so-called onboard controllers. This innovation has reduced rack space requirements – often a key driver for OEMs.
It is worth noting that remote controllers are still preferred if the pump is subject to high radiation where the onboard electronics might be compromised. This is a requirement for high energy beam applications where such an environment is present.
The most recent development allows “smart” onboard controllers which monitor and control valves, pumps and gauges within an automated vacuum system.