Agilent Technologies TV 551 Navigator Bedienungshandbuch Seite 240

17 Technical Information
Description of the TV 551/701 Navigator
The static blades of the stator are made of stain-less steel. These are
supported and accurately po-sitioned by spacer rings.
The Macrotorr stators are in the form of self-positioning machined
discs with pumping channels and an opening restricted by the
corresponding rotor discs. These are made of aluminium alloy.
During normal operation, the motor is fed with a voltage of 54 Vac
three-phase at 715 Hz. To re-duce losses during start-up to a
minimum, the fre-quency increases according to a ramp with a higher
initial voltage/frequency ratio.
The pump can be water cooled or air cooled: in the first case the
customer can use the dedicated channels on the pump body, in the
second case an external optional fan is available.
A thermistor sensor is mounted near the upper bearing to prevent
the pump from overheating.
The pump is balanced after assembly with a resid-ual vibration
amplitude less than 0.01 μm.
The pump can operate in any position and can be supported on the
high vacuum flange. The connection of the forevacuum on the side of
the pump is a KF 25 NW flange.
Figure 10
240/300 TV 551/701 Navigator User Manual / 87-900-934-01 (M)