Pump Used In Presence Of Magnetic Fields; Accessories And Spare Parts - Agilent Technologies TV 551 SEM Navigator Manual De Instrucciones

17 Technical Information

Pump Used in Presence of Magnetic Fields

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 operation, 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.

Accessories and Spare Parts

Tab. 9
Description
Mains cable NEMA Plug, 3m long
Mains cable European Plug, 3m long
Serial cable and Navigator Software
Inlet screen DN 160
Inlet screen DN 200
Water cooling kit (plastic model)
Water cooling kit (metallic model)
Air cooling kit for standard rack controller
Air cooling kit for Navigator controller
268/276 TV 551/701 SEM Navigator User Manual /
Part number
969-9958
969-9957
969-9883
969-9304
969-9316
969-9347
969-9337
969-9314
969-9339
87-900-958-01(G)