Alcatel Vacuum Technology Adixen ATH 1300 M, User Manual

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A 20
The pump operating principle
3/4
GB 00724 - Edition 05 - Januar
y 04
Alcatel Vacuum Technology France - User’s Manual ATH 1300 M/MT - ATH 1600 M/MT
Automatic Balancing
System
The back-up bearings
No maintenance
Battery free
The Automatic Balancing System is an electronic device.
That monitors the rotor position, allowing it to rotate on
its own axis of inertia.
Changes in the rotor balance, due to deposit built-up
during the life time of the pump, are automatically
compensated by the
Automatic Balancing System .
Therefore, there is a total absence of vibration.
They are dry-lubricated ceramic ball bearings.
They are never used in normal operation , since the rotor
is not in contact with the bearings.
The back-up bearings are only used to protect the pump in
accidental air in-rushes, accidental shocks or power failure.
By design, the pump doesn’t include parts liable to wear
and doesn’t need preventive maintenance. However, the
back-up bearings used in case of accidental shut-downs
have to be changed when the controller indicates it: the
percentage of landing time to be deducted depends on its
frequency of use (
see D 10 ).
In case of a power failure, the motor acts like a generator,
supplying enough power for the magnetic bearings.
When the rotation speed is lower than the minimum setpoint,
the pump lands and shuts down on the back-up bearings.
Rotor geometric axis
Stator geometric axis
Rotor inertia axis