Pump Used In Presence Of Magnetic Fields - Agilent Technologies Turbo-V 1K-GRetrofit Manual De Instrucciones

Pump Used in Presence of Magnetic Fields

Magnetic fields induce eddy currents in the rotor of a turbomolecular
pump that tend to oppose to its rotation. The result is increased
electrical power consumption by the motor, most of which is
dissipated in the rotor. Since the rotor is not in contact with the
stator the above power can leave the rotor mainly by radiation and
hence the rotor may be overheated while static parts of the pump
remain cool.
This effect is strongly dependant from the intensity, time function
and distribution of the magnetic field. In general, therefore, an
increase in pump current can be expected. If this increase is lower
than 50 % of the current value drawn by the motor in high vacuum
opera-tion, no particular problem should be expected.
However if the effect is grater, than the case should be carefully
reviewed by Agilent's specialist. As a matter of fact, in case of high
magnetic fields, also important forces might be generated and applied
to the rotor.
Turbo-V 1K-G Retrofit User Manual / 87-900-996-01 (B)
Technical Information

Pump Used in Presence of Magnetic Fields

17
287/294