Connection B - Fore-Vacuum Pump; Connection C - Electrical; Water Cooling Connection; Pump Used With Corrosive Gases - Varian Turbo-V 1800A Bedienungshandbuch

Connection B - FORE-VACUUM PUMP

A flange ISO 63 is available to connect the Tur-
bopump to the fore-vacuum pump. A hose or vac-
uum approved pipe can be used. If a rigid pipe is
used, any vibration generated by the mechanical
pump must be eliminated through the use of bel-
lows.
NOTE
The Turbo pump is characterised by its high com-
pression ratio also for oil vapours. When using a
mechanical oil-sealed pump, it is advisable to in-
stall a suitable trap between the turbopump and
the fore-vacuum pump in order to prevent oil back-
streaming.

Connection C - ELECTRICAL

The turbopump is connected to the controller
through an 7-pin connector. Pins B, G and E are
the 3-phase supply to the motor, pins A and F are
connected to the temperature sensor (NTC type,
30 KΩ resistance at 20° C) and pins C and D are
available for further connections.
The ground cable should be connected to the con-
troller. If the temperature sensor is disconnected,
the pump will not start. To prevent damage to the
pump when the temperature exceeds 60° C, the
sensor automatically cuts out the power supply.

WATER COOLING CONNECTION

The turbopump must be used with the water cool-
ing connected.
To connect the water cooling to the turbopump see
the following figure.

PUMP USED WITH CORROSIVE GASES

To prevent damage to the bearings, an inert gas
must flow into the pump body around the upper
bearing towards the forevacuum line.
To supply the inert purge gas (e. g. nitrogen, ar-
gon) to the pump through the purge port, connect
a gas purge valve between the pressure regulator
and the pump (see the following figure). Adjust the
pressure regulator in order to read a gas flow rate
of 0.1 to 0.8 mbar l/s.
To prevent bearing damage, Varian suggests a
minimum purge gas flow rate of 10 sccm (0.17
mbar l/s). This value can be exceeded, according
to the process requirements. Please contact Var-
ian for specific applications.
The purge gas throughput with the recommended
3
forepump of 15 m
high vacuum pressure in the 10
31
TECHNICAL INFORMATION
CAUTION
/h (11 CFM) allows to achieve a
-8
mbar range.
87-900-867-01(A)