Varian Turbo-V300HT, Инструкция по эксплуатации

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TECHNICAL INFORMATION
37 87-900-875-01(C)
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 consump-
tion 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 radia-
tion 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 Varian's specialist.
As a matter of fact, in case of high magnetic fields,
also important forces might be generated and ap-
plied to the rotor.
ACCESSORIES
DESCRIPTION PART NUMBER
Inlet screen, ISO 100 969-9302
Inlet screen, ISO 160 969-9303
Heater band, 120 V 969-9804
Heater band, 220 V 969-9803
Water cooling kit 969-9337
Plastic water cooling kit 969-9347
Air cooling kit 969-9314
Vibration damper, ISO 100 969-9344
Vibration damper, CFF 6” 969-9334
Vibration damper, ISO 160 969-9345
Vibration damper, CFF 8” 969-9335
Vent flange NW 10 KF 969-9109
Vent valve with fixed delay time 969-9833
Vent device with adjustable delay
time 969-9831
Forepump DS 302, with 1 ph.,
universal motor 949-9325
Forepump MD 60, 120 V 949-9411
Forepump MD 60, 220 V 949-9412
For a complete overview of Varian's extensive
product lines, please refer to the Varian catalog.